Technique Magazine - No. 3, 1984 by USA Gymnastics

THE OFFICIAL TECHNICAL PUBLICATION OF THE UNITED STATES GYMNASTICS FEDERATION

Vol. 4, No.3

Swinging Into A Handstand

Technique Preparation of Articles for Submission: Please follow a un iform format of preparing arti cles for submission in order to provide the most efficient channel through the evaluation and review process. The following should be inclu ded in su bm issio ns: 1. An original type copy, double spaced on BY, x 11 inch paper. 2. an abstract , on a separate page . a short summary of procedure and explanation of study or article content (not more than 150 wor lds) . 3. A short biograpilical paragraph on a separate page of the author or authors accompanied by a small photo (2 Y, x 3 Y2') of the author. 4. References on a separate sheet double spaced in consecutive order, using Index Medicine style (author's name-last name first, name of book , city, publisher, year, page numbers) journal references , should follow same format (author, name of artic le, Journal name, volume, pages, year). 5. Duplicates of pictures and diagrams or figures (black and white preferred) with sharp detail. Also include explanat ions (captions) of pictures and diagrams on a separate sheet. Photograph release-a letter of release from any identifiable subject in photos that are included in the article unless the face or eyes are obscurred. Letter should be signed by subject, parent or guardian . 6. Title page consisting of an informative title , author's name and complete inst itut ional or professional address. Submission of Articles for Publication: Written arti cles will be accepted for review and possible publication in the following procedure. First the articles are sent to: USGF Department of Publications 200 S. Capitol , Suite 110 Indianapolis, IN 46225 Upon receipt of the article, to the USGF office , the research coordinator will review and forward copies to the appropriate USGF Sports Advisory Committee members for review. On receiving their review, cop ies of the artic le will go to the Managing Editor and Executi ve Director for final approval for publication. If it is necessary for the article to be edited or revised in order to improve the effectiveness of communicat ion to a wide variety-level of readers , the au th or will receive the edited article prior to publishing for their app roval. *If the article or parts of have been submitted and / or published by another publication , a complete name and address of the Editor and Publication should accompany the article upon submission to the USGF in orde r to follow proper procedures of publishing and to receive approval to reproduce the article in the USGF publication . Edi torial Staff Mike Jacki , publisher, Debbie Forsten / Managing Edi tor, Mike Botkin / Production Di rector , Dr. Gerald Geo rge/ Educational Research Ed itor. Unless expressly identified to the co ntrary , all articles, statements and views printed herein are attribut ab le sol ely to t he aut hor and t he Uni ted States Gym nasti cs Federati o n ex presses no opi nion th ereon an d assum es no respons ibl ity therefor.

Vol. 4, No.3

, ,, 1

2\ 3~1J PHASE IN THIS DISPLAV PAEHANO CONT FAAAI'ES IN THIS DIS PLAY ARE 1 TO ~ TIME DURA nON _ 05 SECONDS SCALING FACTOR

Table 01 Contents 6 Swinging Into A Handstand, By Fred Turoff, Temple Univ.

8 Director Defines Target Areas, By Dr. Gerald George 10

Listings Of Original Moves By Ted Muzyczko

Aspects of Tumbling Take Off, By Bill Sands, Univ. of Utah

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Technique

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Looking at Two Skills The Full-In: A Methodology The Gymnast and the Warm-up Overtraining Compositional Analysis: Uneven Bars Observations of Training: Female Foreign Gymnasts at the 1981 American Cup

Joseph E. Donnelly

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Technique

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Swinging Into A JflLandยงtand From A Hang On The Rings By Fred Turoff Head Coach of Men's Gymnastics Temple University Philadelphia, PA Abstract discuss the mechanics of straight arm swings to a handstand from the bottom up with an explanation of the bodily movements and the relationships between backward and forward swings. The technique of picturing a movement and then using the mind 's eye turning the head around to see a related movement is demonstrated.

his discussion will talk about the mechanics involved in swinging to a handstand with straight arms. I have chosen to concentrate on this movement from the bottom of the swing to the handstand, so the mechanics of dislocates, in locates, and drops from a handstand have been omitted on purpose. Before beginning the discussion, I must define some movement terms . Shoulder Flexion: Moving the arms in the direction followed when lifting them from a position by your sides in a forward then upward manner until they are overhead. A good handstand has the shoulders completely flexed (the term extended is often incorrectly used). Shoulder Extension: The opposite movement of shoulder flexion. A hang rearways has the shoulder hyperextended, as complete-extension is defined as having the arms by your sides. Shoulder Abduction: Moving the arms in the direction followed when lifting them from a position by your sides to overhead laterally (sideways) . Hip Flexion: Moving in the direction followed when going from a layout to a pike. Spinal Flexion: Moving in the direction followed when going from an arch to a hollow. Hip Extension: Opposite of Hip Flexion Spinal Extension: Opposite of Spinal Flexion Pronation: An action of the forearms - for example, with the arms held out horizontal in front of the body, turning the palms from facing up to facing each other to facing down. Supination: Opposite of Pronation There are several important factors involved in swinging to a handstand , which are: 1. strength of the muscles involved ; 2 . speed going into the movement; 3 .

range of motion of jOints involved ; 4. kinesthetic awareness. Regardless of the gymnastic movement attempted, the stronger you are the greater your joints' range of motion (flexibility) , the easier it will be to learn . This cannot be emphasized enough . Lead up skills help you get kinesthetic awareness and strength. Good series of dislocates and inlocates plus a strong handstand are necessary to be successful in learning this skill. I'll begin discussing a shoot to handstand as would be done after a dislocate or from a handstand (giant swing) . Once the body passes the bottom of the swing , you must get upside down as fast as possible. To do this requires a fast flexion of the hips and spine, and extension of the shoulders. Refer to these stick figures :

n figures 2, 3, and 4 we can see these actions. Note the shoulders have not started to rise yet. The forearms will be pronated at this point as well. Once the legs are verticle or close to it, the hips will begin to extend powerfully, and the shoulders extend a little more, and the forearms supinate (5). By the next figure (6) we see the shoulders have reversed their movement and are flexing as the hips (and spine) continue to extend. This continues until a stable handstand is reached . Several points must be made about these actions. The speed coming into the movement will determine how much hip flexion is required and how much lateral movement the arms will have . Note that in figure 4 the legs are practically vertical. This is necessary for a precise, vertical shoot from a medium swing . If the body does not turn over enough prior to the extension of the hips, then the body will move in front of the rings (possibly picking up swing) and the arms will

have to move laterally from figure 4 to 8 to some degree to bring the rings under the body's center of gravity (c.g.) to obtain a balance at the end of the movement. If there is lots of speed going into the movement , and a strong turn over is effected, then the arms may stay close together on the upward phase of the shoot (5-8) to counter this rotation , and you may not need to flex the hips as much as in figure 4 before extending the hips. As you get stronger in the shoulders , you may do more of this turn over with via shoulder extension and less with hip flexion . A lack of speed into the movement will necessitate wide arms on the shoot so that you don't lose balance (over counter-rotate) on the way up. Now with your mind's eye and my pen, let's look at these figures

again with one change - turn the head around : This looks very much like a backward uprise to a handstand, doesn 't it? Due to anatomical limitations, I'm going to change these figures a little bit (from 3' -8'). What do these stick figures show? Figures 2A-5A demonstrate a powerful inversion of the body as in figures 2-5 for the shoot. A fast inlocate is necessary. Since we humans are much stronger in actions of shoulder extension and hip and spine flexion (starting a shoot) than we are at shou lder flexion (and getting to hyperextension via inlocation) and hip and spine extension , it's harder to turn over and usually we won 't want to counter rotate our bodies by moving the rings as in figures 4'-8', so we have to keep the rings anatomically below the shoulders (on these stick figures to the right of the shou lders)

Technique

around figures 5A & 6A. The arms here are quite lateral. The arms continue to press downward on the rings coming from a hyper-extended position behind the body with forearms pronated , and move laterally from figure 3A to 5A. At this pOint the body is almost vertical and the shoulders continue abducting and forearms supinating until a handstand is reached . If insur~cient turn over is achieved from figure 2A-5A then it will be necessary for the hands (rings) to be closer to the c.g . so as to retard the rotation less (or in extreme cases to add to it) . In this instance the arm action is more through a planche to handstand than through an inverted cross to handstand (i .e. more shoulder flexion than abduction). You can see the need for a great range of motion of the shoulders here. If you cannot inlocate fast and efficiently, you 'll have trouble doing this movement unless you are extremely strong . Note in the figures that the rings are displaced considerably during these

movements. Since the rings are light and move easily, the body rotates not only about the rings , but also about its c.g. To avoid picking up a ring swing , the c.g. must stay directly under the point of suspension of the rings . The path followed by the toes is somewhat elliptical , by the rings is an arc, but by the c.g. should be pretty much a vertical line. This is an important consideration in analyzing causes and cures for ring swing . (The dotted line here is the first half of a giant swing. ) So why do bent arm swings to handstands? The reasons are simple . With the arms straight, the lever arm that your muscles are working with is long compared to a bent arm and therefore with bent arms, you are able to go through these movements more easily until your shou lders get strong enough to handle the longer lever of straight arms . For backward uprises, another reason is that if your shoulders are tight, you can inlocate easier with bent arms as the upper arm will be more lateral during the action . Generally, the beginner

gymnast doesn 't have the physical capabilities for straight arm work. As the gymnast progresses through the sport , repeats these movements many times ,. and does supplementary strength and flexibility exercises , he will realize the rewards of hard work as he develops his bent arm swing to handstand (a B move in either direction) into a straight arm swing to handstand (a C move in either direction) .

Biography of Fred Turoff . June 1984 Fred Turoff has been head coach of men 's gymnastics at Temple University for the past eight years . As a competitor, he was on four U.S. teams, including the 1970 World University Games and 1970 World Championships teams . He was the assistant coach of the 1979 U.S . World Championship Men's team . He has both national and international judging licenses, and is the current president of the NACGC (M) .

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Technique

Director Defines Target Areas

he USGF has recently established the Department of Education & Safety. It's fundamental purpose will center upon the development, implementation & evaluation of a safe and effective " national program system" for the teaching , learning and performing of gymnastics at all levels of involvement. The department's primary target areas are : 1) professional teachers and coaches associations; 2) recreational & competitive gymnastics programs; and 3) professional gymnastics judges associations. The objectives specific to our Professional Teachers and Coaches Associations include : 1. To conduct strategically planned nationals & regional coaching seminars and symposia . 2. To develop and implement a National Gymnastics Safety Certification Program . 3 . To develop and imp lement a National Gymnastics Coaches Certification Program . 4. To develop a recommended course of study (undergraduate/ graduate credit) for prospective Physical Education majors interested in the teaching and coaching of gymnastics. 5. To serve as a resource library, clearing house and publications outlet for the gymnastics industry at-large. The Recreational and competitive Gymnastics Programs are , without question, our fundamental "reason for being " and , as such, must receive a top priority in terms of emphasis. The USGF is currently planning programs of national scope that will help to accomplish the following objectives: 1. To broaden the gymnastics participation base and particularly at the " Grass Roots" level. 2. To improve both the quality and level of gymnastics participation for all age groups of both sexes. 3. To develop an accurate and working technical knowledge of core movement patterns and sequences , particularly in terms of their relationship to the more progressive and complex skills and combinations . 4. To serve as a fundamental resource unit for our National Gymnastics Developmental Programs. 5. To lend assistance and direction to our National Technical Committees in terms of preparation, training and evaluation to national and international gymnastics competitions. The "silent partners" affecting both the direction and quality of gymnastics in the United States rests on the shoulders of our Professional Gymnastics Judges Associations . The

associations influence the standards throughout our industry as well as help to determine the quality of over developmental programs. The USGF plans to work very closely with these associations to provide the following assistance : 1. To lend assistance and direction to our National Judges Associations in terms of both the development and interpretation of compulsory exercises as well as the techni cal evaluations of optional skills. 2. To serve as primary consultants to our National Judges Associations specific to safety and analysis of new andl or innovative skills and techniques. 3. To work closely with our National Judges Associations specific to standardizing the operational guidelines and procedures for gymnastics competitions . In order to help promote the kind of credibility & services so essential to the success of our programs and their objectives , the Department of Education & Safety is currently in the process of formulating 6 primary support committees (see Figure 1). The heads of these various committees will serve as the USGF Steering Committee and will be charged with the following responsibi lities: 1. To promote the conduct of original research into the sci entific aspects of gymnastics. 2. To serve as an editorial review team for the USGF publications department. 3. To disseminate relevant scientific and technical information to teachers , coaches, gymnasts and judges via USGF publications, workshops, seminars and congresses . 4. To direct and coordinate the collective workings of the sub-committees The USGF is and will continue to be unquestionably committed to the development of viable educational, developmental and safety programs. This is indeed a new and exciting era for gymnastics in the United States. And yet the level of this success in these endeavors will be primarily dependent upon the active support of our gymnastics professionals. Consequently I am asking those of you who feel they have something to offer and who want to play an important part in reaching out and helping our kids, to do so by applying for membership on one of our six support committees. Please include a brief resume (vita) specific to your professional and/or gymnastics background and address your letter to my attention. Gerald S. George, Ph. D. Director of Education & Safety

Figure 1 Administrative Flow Chart for the USGF Department of Education and Safety

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USGF Editorial Staff Publications Department

â&#x20AC;˘

USGF Steering Committee Heads of sub'committees

Sports Medicine subÂˇcommittee

Biomechanics sub-committee

Exercise Physiology sub-committe

Sports Psychology sub-committee

Education sub-committee

Safety sub-committee

Technique

the

OFFICIAL USGF GYMNASTICS SAFETY MANUAL Edited by: GERALD S. GEORGE, Ph.D. USGF Director of Education & Safety

A comprehensive guide for the promotion of safe learning environments for gymnasts at all levels of involvement. Designed to raise the level of safety awareness of the entire gymnastics industry. Will serve as the official manual for the USGF Safety Certification Program. Covers the major safety areas of concern including: Legal and medical responsibilities Environmental safety factors Spotting and gymnastics safety Performer readiness Trampoline safety Gymnastics skill progressions Educational and safety materials

** ** ** *

A MUST for every serious gymnastics professional Available JANUARY 1985!

To be placed on the USGF Educational and Safety Programs mailing list, please fill out the form below and return to: u.s. Gymnastics Federation 200 S . Capitol Avenue 1 Hoosier Dome. Suite 110 Indianapolis. IN 46225

Name ______________________________ Address ___________________________ City ______________ State _ _ _ _ Zip _ _ Phone~(____~_______________________

Coach _ Judge _ Gymnast _ Club Owner _ Other _

Original Moves Described, Valued, Assessed By Ted Muzyczko

Editor's Note: This is a continuation of Ted Muzyczko's story "The Use of ROV In Judging The NCAA Men's Gymnastics Finals" which appeared in 'Technique' Vol. 4, No.2.

LISTINGS OF ORIGINAL MOVES he NGJA has published a list of potentially new or original moves. These are updated annually. The latest 1983-84 Supplement contains almost 200 moves that are not in the FIG Code or other publications. This supplement describes the moves, and their difficulty values risk assessments. As FIG rates these moves, the NGJA will automatically incorporate the FIG values, to be in concordance . Also, this supplement includes the new vault values that were used throughout ,the 1983-84 NCAA season. These of course have been approved by the NCAA Rules Committee . A number of moves that are in the Code and the NGJA Rules Interpretations Book are still considered to be original, since they are not performed frequently. Examples include: the double saito with two twists (floor exercise, still rings and horizontal bar) ; the triple saito dismount on still rings ; the " Manna" on one bar (parallel bars). The judge must use his experience in determining which of the listed moves are original. As an aid and guide to making judgments, the following Table 2 lists the number of the moves in the NGJA 1983-84 Supplement, that have a high probability of being considered original. Also included is the latest FIG supplement (HC bul letin) list.

TABLE 2 LIST OF SOME POTENTIALLY ORIGINAL MOVES (NCJA 1983-84 SUPPLEMENT AND FIG BULLETIN) FLOOR EXERCISE NGJA LISTING Russian Moore. C Circles with spindle . CR Flair circles with spindle . BCR BC Diamidov to one hard handstand (2 sec. hold) . Front saito to back saito. BB Front saito with 1'12 twists (rudy) to punch front saito. CCR Full tiwsting front 1'!. saito. CCR C Front handspring with 1 '12 tiwsts. CR Tsukahara back saito to chest roll. Tsukahara back saito to stand. CCR 1 V2 twisting back handspring . C One arm back full twisting handspring . C B Back full twisting head roll. Full twisting back saito, punch front saito with '12 twist. CC CCR with full twist. Full twisting back saito, to double back saito . CCR Double twisting back saito, to double back saito. CCRR Back 1'12 saito to prone position . CR CCR Double back saito to punch front saito . to punch front 1'!. saito. CCRR Back in , fu ll out, double back saito. CCR Double twisting double back saito. CCRR Back saito with 1'12 twists to punch full twist drive roll. CCR Front 1% handspring (front handspring without touching feet to handstand rollout) . CR Front 1'!. saito with full tiwst. CCR

FIG BULLETIN RIO Saito backward with 1 % turn and saito forward to front leaning support Saito backward with 2/1 turn and saito forward One, two temposaltos backward , saito backward with 1/1 turn and saito forward Double saito forward Double twist 1 '12 saito backward with 1'12 turn to roll forward 1 '12 twist to roll froward Double saito backward with 1/1 turn and at the end of the movement with 2/1 turn Double saito backward stretched Double saito sideways 1'12 saito sideways with '/4 turn to roll forward Saito sideways with 1/1 or 1'12 turn Triple saito backward Flic-flac with '12 turn , handspring forward with '12 turn , jump backward with 1 V2 turn to roll forward Roll backward to handstand and immediately lower with spreading of arms to Japanese handstand I hold 2 sec. I One arm handstand, lower sideways to ÂŤMalejewÂť strength handstand Pointed angle support I body in horizontal position , 2 sec. I Magyarspindel Thomas with '12 turn to handstand Free support scale with straight arms Press handstand with straight arms and straight body POMMEL HORSE NGJA LISTINGS CCR Double Bailie on one pommel. CCRR Reverse cross support travels (Sivado) . BCR Front in to 1'12 pommel loops. CCR Kehre on one pommel , 540 0 (1 V2 rotations) Loop flair circle to handstand dismount. Loop flair to pirouette to loop circle. CR Loop to back saito dismount. CR Loop to handspring dismount. B CR Back loop circle to front saito dismount. Back work done in reverse directions. C Back moore with hop travel. BC Magyar travel with flair circles. CCR Behind the back hop to end of the horse immediate flair to handstand CR (Daggett) . Back stockli flaired to handstand WIOC (Bilozerchev) CR Flair travel from one end of the horse to the other end without pommels. CCR FIG BULLETIN RIO Two double leg circles in cross support with Travel backward from one part of horse to the other Double leg circles in cross support and Travel I 4 circles with Trave l backward from one end to the other I Schiwado I Travel hop sideward from support or support rearways Two times Travel hop sideward wo.i.c. Travel hop in opposite sense From the support rearways on the horse body Drehflanke with 1/1 turn to the support rearways on the end of horse / without support on the pommels From the support rearways on the end Drehflanke with 1 V2 turn / or more I to the support on the horse body I without support on pommels 1- for ex. double Russian wende swing from the end to the horse body without support on pommels Magyarspindel Magyarspindel on one pommel '12 Magyarspindel with Travel ITkatschew, Ditjatinl

Technique

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Magyar Travel with turn ISpindel1 or two Travels with '12 turn each IGuzhogyl Double rear with 1/1 turn around the support arm 4 times double rear on 1 pommel 1M. Nikolayl 2 times double rear on one pommel followed by a Drehflanke with 1/1 turn on the same pommel 2 times double rear on one pommel , '12 turn with Travel Thomas Without turns and without Travel Thomas on one pommel 1M. Nikolayl - Thomas to handstand on one part of the horse may be also connected with dismounts: with straight body IKoroljow/, Cartwheel ISut/, handspring forward 0,2 - Thomas in cross support with Travel forward 0,1 - Thomas with double Travel forward 0,2 - Thomas with Travel backward 0,1 - Thomas with double Travel backward 0,1 - Thomas and Travel backward in cross support 0,1 - Thomas with double Travel backward in cross support 0,2 0,1 - Half Magyarspindel with Thomas - Magyarspindel with Thomas or two '12 Magyarspindel with Thomas 0,2 - Scissors outward or inward with or without turns to handstand I also with dismounts I 0,2 - Two scissors with Travel hop sideward each 0,1 - Twice scissors with '12 turn Iforward to scissors backward with '; ' turnl scissors with Travel hop sideward 0,1 - Scissors with '12 turn and Travel hop sideward 0,1 STILL RINGS NGJA LISTING Front saito from support to support without releasing the grip. CR Straight arm back kip to Maltese. BC One ring front lever. B Press to handstand from Delchev support. C Handstand to back lever hold (2 .sec.) with straight arms. B with bent arms. A '12 turn to kip L. AB Front straddle saito to catch. C From handstand , snap down to 1V2 back saito . CCR Swing movements in which the straps cross, RAISE DIFF. FIG BULLETIN RIO Cross I hold I and pull-up to support I «L» support I Cross series I simple, in «L» position , with turn From hang vertical pull-up with straight arms to cross From hang felge with strength backward straight arms to cross IAzarjanl From cross felge with strength backward straight arm to cross I or through cross to support or «L» support I Stem me to cross I stemme forward , backward , felge backward Inverted cross I not too high , hold I From inverted cross pull-up to handstand Stemme backward to inverted cross Free support scale with spreaded arms Feige or stem me backward to free support scale Press handstand with straight body and straight arms above move from free support scale From hanging scale rearways press with straight arms to cross, free support scale or handstand Series of strength parts I at least 3 B or C I From handstand lover to inverted hang and kip to support From backward swing in support fall forward to bent inverted hang and stemme backward to high support or to handstand Kip to pointed angle support Stem me backward with straight arms to high support or to handstand From backward swing in support fall with '12 turn to hang I ropes crossed I and stemme with '12 turn to support Double saito backward with body extension during the fl ight Double saito backward stretched with turns Double saito backward piked with turns Double saito backward with 1'12 turn I or more I Triple saito backward Triple saito backward piked - tucked Triple saito backward with turns Double saito forward piked Double saito forward with turns

Technique

PARALLEL BARS NGJA LISTING AB Early drop to straddle drop kip to straddle C Stalder shoot mount on one bar. One bar, overshoot to immediate kehre in . B One bar, inside bar kip to L or V (Cahoy). C One bar, glide kip , cast to front saito catch. BCR One bar, glide shoot to dislocate cut catch. C CR Stem between the bars to V2 turn to pirouette in . Glide stoop in to german uprise to V seat, on one bar. BC Side bar swing under to flyaway. B to flyaway with full twist. C B Full twisting dive roll mount to upper arms. From board , front saito to support. CR From side, dive to cartwheel mount. B Front uprise to Diamidov. CCR Front uprise to reverse hecht. CR Front uprise to % twist over bar to glide. B One bar glide kip cast and hop pirouette to the far bar. C Back uprise to Voronin vau lt. B Back uprise to immediate front 1'!. saito . CR Back uprise to immediate healy twirl. CR Giant swing to immediate straddle cut. CCR Giant swing to Delchev saito, on the end . CCR in the middle. CCRR Reverse hecht to immediate % saito. CCR From support roll forward over the grip below the bar and kip to sup~.

Stutz to one bar. C CR Back toss to one bar. CCR Back toss with full twist to catch. CR Stutz to front saito to : upper arms . CCR support. BC Giant to double back dismount off the end. CCR Double front dismount with '12 twist. CCR Double back saito layout. CCRR Double back saito with twist. Triple back saito. CCRR Over bar stutz to front out dismount. C CR Over bar stutz to front out dismount with V2 turn. From handstand on one bar, snap down to full twist saito off. CCR Giant to full twisting back saito dismount over the side of the bar. CCR Side bar giant swing to hop to other bar. CR CR Front saito, over the bar, '!. turn , regrasp to glide. Flair in the middle of the bars. C FIG BULLETIN RIO Giant swing backward Giant swing backward with turns Saito backward from forward swing in hang at ends of bars , stretched , with straddled legs, with turns a.s.o. Double saito backward at ends of bars, tucked , piked Above move with 4 turns Swing backward , drop to forward swing in hang and felge backward with straddle cut catch to support in the midde of bars IKoroljowl Saito forward piked with straddle cut catch to support Above move and rearward swing to handstand Saito forward with 1/1 turn to support Saito forward with straddle cut catch backward to support IHonma/ Saito backward with straddle cut to bent arm support Double saito backward to upper arm support or to hang Rearward swing in support and 1/1 turn to upper arm support Above move to rearward swing in support From upper arm support stemme forward with '12 turn to handstand Above move with 1/1 turn IDiamidov from upper arm support! Stemme forward with 1 V4 turn to handstand on one rail Stemme forward with straddle cup catch backward to support Stemme backward with V2 turn and double leg cut backward under one arm to support 1V0ronini Stemme backward with V2 turn and straddle cut catch to support Cast with '; ' turn to support or to «L» .position Cast with 1/1 turn to upper arm support

(Continued on page 14)

MEN'S GYMNASTICS - NCAA INDIVIDUAL FINALS JUDGING RULES SUMMARY COMPETITION 3 RULES BASE SCORE 9.0 Max BONUS POINTS 1.0 Max RISK ORIGINALITY

.3 Max 0,.1, . 2, or.3 if Originality is .5 Maximum DEFINITION - Listed C Parts (code or NGJA supplements) or new C Parts in which execution faults do not exceed .2 for those parts

• 7 if R = .1 .6ifR=.2 .5 if R = .3 Also .4,.3,.2,.1 or 0 Without Restrictions

DEFINITION - Any new parts (series of A's B Parts, C Parts, sequences or whole exercises) for which no final deduction has been made for execution errors. Each judge determines what is Ori~inal based on his viewing experience and the frequency of Part performances. Also see the list of potential Original moves prepa r ed by the NGJA (1983-84 Supplement). Not all of these are Original, but some are. These moves have been reviewed in Certification Clinics. •

Any new "Original as the individual judge sees it" group of three or more A moves, a -B or a -C part may receive: up to 1/10 for the 3A parts; up to 1/ lofor the 13 part; up to 2/10 for a C part.

•

Any sequences of three moves, that are Original in their combination in which at least one is a B or C part, can receive up to 2/10 for Originality.

•

A new technique of part execution can be considered as Original. Award up to 1/10 for each part so performed. An example of this would be a straddle piked back saito in Floor Exercise. This is a whole new Original techhique .

,------------------------------------------------------------------.

If less than II parts, deduct up to .4. (Suggest: to parts -.2; 9 parts -.3; 8 parts - .4). 3C, 3 B, 2A parts required and total of II parts.

Floor Exercise: l.

Still Rings:

l. Two swinging C parts required. If one shown deduct .2, under combination If none shown deduct .3, under combination

Two swinging C parts required. If one shown deduct .2, under combination. If none shown deduct .3, under combination. Technique

- ,.. -

1.0

I 1.0

:1M

VIRT UOSITY . 2 Max

0, â&#x20AC;˘ 1 or . 2

DEFI NI T ION - Any part, sequence or entire exercise executed with form exceeding current minimum s tandards--and that does not raise that part or sequence to a higher difficulty category. Given for flawless performances only for Grouped A Parts, B Parts, C Parts, sequences or the entire exercise . â&#x20AC;˘

An entire exercise can receive up to 4/10 for Originality. A gymnast has a repertoire of eleven nominal parts to show you what his combination possibilities are. R + 0 = .8 Maximum, and R cannot exceed. 3 nor can 0 exceed . 7. Further, V Cannot exceed .2 Any single part cannot be given more than .4 for R + 0 + V

Note, all Original C or CC dismounts or landings in floor exercise passes can be judged more leniently if the potential execution error is not more than .3 points for that part. This interpretation is within existing rules, since "up to" .5 may be deducted for dismount/landing errors. Simply deduct less. This has been used internationally and is reasonable. Note, this applies to vaulting as well. An example would be an Original floor exerCise tumbling pass that has the C valuation mentioned above. If a gymnast has a potential deduction of .3, you may deduct only . 1. In other words, you may deduct less by an amount of .2 but not more. Another example is if a gymnast lands from a high Original C dismount on the horizontal bar and the potential deduction is .2, you may ChOOSE to deduct nothing. But in no case should the "leniency" exceed. 2 points . Further, if a gymnast incurs .3, .5 or more deductions on the landing or pass, then this rule does not apply. We want to encourage gymnasts to do Original movements, but these must be under control. For Original Parts that do not involve landings, use the existing r ules and your judgement.

Parallel Bars: I.

Two swinging C parts required. If one shown deduct .2, under combination. If none is shown deduct .3, under combination. One swinging C must be executed through an inverted hang or glide hang. If none is shown deduct .3, under combination.

Technique

(From page 11) Cast backward to support Cast backward to handstand I without use of strength I Cast backward with '/2 turn to support Feige to handstand I straight arms I Feige with V, turn to support Feige with '/2 turn to handstand Feige forward I Martschenkol Above move with V2 turn to support I drop forward to inverted hang and kip with V2 turn to support I Double salta backward piked -stretched Double salta backward stretched Double salta backward with turns Triple salta backward Double salta forward piked Double salta forward tucked with early body extension Double salta forward with turns HORIZONTAL BAR Cross arm overgrip sale circle . Cross arm stalder. Stoop in to % elgrip swing to immediate hop pirouette . Kip cast to overgrips, reach under to double undergrips . Stoop in to two inverted giants to hop pirouette. From overgrip swing , stoop in and straddle cut to support. Sale circle shoot to 1'/2 twists. Sale circle shoot to '/2 turn to inverted giants. Sale circle stand , back full twist salta to catch (Korbut). Free hip to immediate straddle cut to stoop circle . Free hip, flank cut with V, turn. ana turn to one arm front giant. Front pirouette to one arm giant to direct change . Hop with full turn over the bar to one arm giant. Front pirouette to one arm giant to higgins turn . Full twisting one arm giant. Healy twirl to one arm giant. 1 V, twisting flyaway regrasp (Gienger). One arm giant to flyaway V, reg rasp . Reverse hecht to immediate flyaway V, reg rasp . Full twisting front salta to catch . V2 twist in to Gaylord flip . One arm giant to reverse hecht (McCutcheon) . Wrong grip giants. Undergrip. Overgrip. 1 V, twist flight over the bar to catch . Free hip shoot to 1 V, twists . Hip circle hecht with V, turn to catch . Back uprise with V, turn to german giant over the bar. Kip cast to full twist catch . German uprise to reverse straddle cut catch. Triple front salta with V, tu rn (triffus). Full twisting triple back salta. Hecht front or front with V, twist dismount. Back uprise to back salta dismount. Double twisting double flyaway . From giant swing backward on one arm : Two giant swings in succession . Turn to one arm elgrip followed by V, turn to overgrip giant. Turn to one arm elgrip followed by full turn to underg rip Reverse pirouette. To Higgins turn . Releases from one arm giant: Gienger, Delchev, reverse hecht, etc. From giant swing forward on one arm (undergrip) : Forward giant, pirouette to one arm back giant. Pirouette at bottom to two arm overgrip giant. Healy twirl (full turn) to one arm giant. Healy twirl to one arm giant followed by '/2 turn to overgrip. Release from one arm giant to Jaeger, Markelov.

C CR BCR B BCCR

C C

CC CR CR

C CCR CR CCR CCR CR CR CCRR CCR CCRR CCR CCR CCR

C B CCRR CR CR CR

C CR CCRR CCRR

C B CCRR

Release from one arm to Voronin , straddled forward and catch in hang rearways .

CCR

FIG BULLETIN RIO Simple giant swing backward or forward on one arm Giant swing forward with V, turn to hang on one arm and giant swing swing backward on one arm Giant swing backward with V2 turn IKelerowl to hang on one arm with reverse grasp and giant swing forward on one arm Giant swing backward on one arm with V, turn to hang on one arm with reverse grasp Giant swing forward on one arm with 1/1 turn to hang on one arm with ordinary grasp Giant swi ng backward and forward with turns ÂŤthere and back .. in hang Elgrip giant swing with 1/1 turn to giant swing forward on one arm Elgrip giant swing with V, turn to giant swing backward on one arm Giant swing backward or forward on one arm with change of arms I giant swing on left and then on right arm I At least 3 giant swings on one arm without touch ing the bar with the oth er hand Salta to the hang , flying parts or dismounts from giant swings on one arm Deltschev, Gienger Salta with body extension Salta with high flight l over the support level I Salta with high flight, regrasping the bar with straight arms and with following swing of great amplitude Salta with 1 V, turn Salta forward to hang Piked Piked and with high flight Stretched With 111 turn Salta backward to hang with flight over the bar I also as dismount I Salta backward first bent then stretched to hang Double salta backward tucked to hang Double salta backward piked Double salta backward stretched I piked-stretch ed l over the bar to dismount Above move with turns Triple salta backward over the bar to dismount Optional combinations of Voronin , Tkatschov, Deltschev, Gienger saito forward to hang and so on Dismounts Double salta backward stretched with 1/1 turn or with 2/1 turn I or more I Triple salta backward or - and with piked - tucked I tucked - piked positions Triple salta with turns Double salta forward slightly piked or and with turns Triple salta forward

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Aspects Of The Tumbling Take Off () Abstract Aspects of the Tumbling Take Off Bill Sands University of Utah

wO advanced colleg iate female gymnasts were filmed at 80 frames per second performing a round off to back handspring and layout backward somersault. Gymnast A was selected due to a previous injury of two spinal stress fractures while Gymnast B was selected due to her more typical performance techn iques and ach illes tendon injury. The subjects were filmed, and the fi lm was digitized using the model for female gymnasts by Kjeldsen (1971) . Digital filtering was done by the Butterworth Digital Fi lter at 10Hz for all body parts but the ankle which was fi ltered at 12 Hz. The data was stored in a microcomputer and further quantitative analysis and graphic output performed by software written by the investigator. Range of motion data indicated that Gymnast A had made adjustments in her tumbli ng technique that limited the range of motion of her spine and related joints as compared to Gymnast B who represented a more typical performance technique. Recommendations were also made to determine quantitative reasons for Gymnast A's more competent take off techn ique as compared to Gymnast B.

he coach is cal led upon to analyze the mechanics of skills hundreds of times each training session . The coach's abi lity to perform an accurate "task analysis" is much of the secret behind giving the ath lete the feedback necessary to enhance the performance of the skill. The following look at take off mechanics is an example of one method of determ ining some of the actions which underlie performance. Biomechanics is a science dealing with the engineering behind ski lled performance. This type of analysis seeks to determine the workings of a ski ll in the language of physics . The information gathered can uncover some subtleties of the movements that are difficult to see with the unaided eye. I have rewritten the fo llowing to remove most of the scientific jargon but some must remain to avoid misunderstand ing. Wherever possible an explanation of an unusual procedure or concept has been placed in a " Research Detour" and explained. If you are not interested in the research portion then simply disregard the detour and continue read ing on.

Procedures, Methods, and Assumptions WO fema le gymnasts were filmed at the University of Utah during the fall of 1983. Gymnast A was 19 years old, weighed 50.90 kg (112 Ib) , was 1.90 m tall (5 ft, 3 in), and was a former elite level competitor. Gymnast B was 21 years old, weighed 45.45 kg (100 Ib), was 1.57 m tal l (5 ft, 1 in) , and was a former elite level competitor and a member of the U.S. National Team. Each gymnast performed two tumbl ing series of round off to flip flop, followed by a layout back somersault from four or five approach steps. All the tumbling was performed on an AMF coi l spring and carpeted floor exercise area. I decided which attempt was the best for each gymnast and analyzed that particular tumbling pass. The filming was performed by a Beaulieu 4008 ZM4 camera that uses super-8 fi lm and supplies a frame rate of

80 frames per second. The film was Ecktachrome 160 ASA, shot at f1.4 . The film speed was checked with a conical timer placed in the field of view. The camera distance was 14.60 m (48 ft) from the plane of action and perpendicular to it. Camera height was 1.5 m (5 ft) to the plane of the fi lm. Landmarks on the gymnasts' bodies were identified with high contrast tape . Two reference pOints were used for frame alignment and meter reference distance. The total viewing area was 6 m wide (20 tt) and the camera focal axis was placed in the center of this area. (Refer to Research Detour 1).

Research Detour 1 The information about the filming circumstance is important to the researcher so that if others want to try the same experiment themselves then they will be able to duplicate the same conditions. Science relies upon this "replication of results" in order to verify an experiment. A single study proves nothing, only after several replications of the original study can one assume that the results are probably true. The filming must be done at high speed. Eighty frames per second is fast enough to resolve most gymnastics skills. The need for high speed film is to avoid the small blurs that occur when the film speed or shutter speed is too slow to adequately freeze the motion of the athlete in the frame. The process of digitizing is so fine that the digitizer can resolve the distance between the toes of the foot so you can see that any blurring will add a lot of error to the results of calculations done based on body part position in space. This is the reason for using high contrast tape on the body landmarks, so that they are easy to find and error in locating them is minimized. The fi lm was processed and then projected on a Bell and Howell super 8 film projector that has been converted to maintain brightness and provide single frame advancement for digitizing . The film was projected onto a beh ind-the-back screen for digitizing. Each frame of the film was digitized using a Numonics Digibit digitizer. The digitizer marker or cursor is placed above each of the gymnast's body landmarks in a specified order for each frame . The digitizer sends the location of each body landmark to the computer in an x - y coordinate format. Each frame was digitized twice and the average of each data paint was stored on floppy disk for later calcu lation and analysis . If the average of the data point differences was more than 2.0 data points then the frame was rejected by the computer and had to be digitized the frame again. The digitizing consists of locating 18 landmarks, identifying 15 segments, and 14 jOints. The model of the human body used for determining the percentage weights and location of segment centers of mass was based on the model provided by Kjeldsen (Plagennoef, 1969). This model was determined by examination of collegiate age female gymnasts. The segment landmarks and the total body center of mass were stored on a floppy disk in a TRS-80 Model IV microcomputer using software designed and written by the investigator. The center of mass calcu lation was performed by the method described by Hay (1973).

Research Detour 2 The digitizing process is what the biomechanist uses for data collection. This process gives the computer an x - y coordinate "map" of the body for each frame. The body is reduced to links or segments that are

Technique

(

assumed to be rigid and extend from one joint center to another. This makes a sort of stick-figure in computer terms that allow us to compare and calculate the range of movement of each body part, the relation of each body part to every other body part, the speed of the movement, etc. The computer also receives a reference distance by digitizing the length of a meter in the very beginning so that we will know how far a meter is in the x - y coordinate reference system. This allows us to scale the distances traveled by the various body parts much like you might scale the distances on a geography map. Then if we also know how many frames per second are shot by the camera we can tell how far a body part traveled in a specific period of time by comparing where the body part is in one frame and how far it moves in the next frame. Then we have velocity, because velocity is defined as distance divided by time. Velocity = Distance Time The distances will be very small portions of a meter and the time between frames at 80 frames per second is .0125 seconds. This gives us lots of information that we can use later in other equations by performing some slightly more sophisticated calculations. The raw data was filtered by the Butterworth Digital Fi lter with a frequency cut-off of 10Hz for each data point except the ankles which were fi ltered at 12 Hz. Each data point path was examined on a TRS-80 drum type plotter with a horizontal resolution of 1960x and a vertical resolution of 2000y. The raw data curves were fitted with the filtered data curves by trial and error to determine the cut off providing the best fit. The digital filtering is done to reduce the " noise" or small digitizing errors that result from human error, blemishes in the fi lm, etc. The paths of the data po ints are typically bumpy due to this error and the digital fi lter makes the lines smooth without changing the path of the body part. Th is will make later calcu lations more likely to be accurate since the actual movements of the body parts are not bumpy but very smooth . All the frames were digitized beg inning 3 frames prior to hand contact of the flip flop. Phases of the skil l were named by the investigator to permit easy comparison between the gymnasts. Calcu lations were then performed on the fi ltered data to determine the following: 1. Resu ltant velocity of each body part landmark. 2. Horizontal and vertical component ve locities. 3. Acute angle of each joint 4. The velocity of the angle change of each joint. 5. Resultant accelerations of each body part 6. Horizontal and vertical component accelerations 7. Time duration of each phase of the skill 8. Moment of Inertia and radius of gyration Some assumptions have to be made in all scientific investigations. Some assumptions are simply things that are out of our control or are made due to an accepted understanding of a phenomenon that need be mentioned so that results are interpreted with these limitations in mind . 1. Take offs from an elastic surface shou ld utilize maximum speed and minimum time. The athlete who is off the floor with the greatest speed and on the floor the least time during the take off wi ll have the best take off (Hochmuth & Muchold, 1978). 2. Deflections in the path of the center of mass in directions not appropriate for the intended path of the center or mass are considered inefficiencies. 3. Analyzing the technique of a performer involves the determ ination of a few phases of the ski ll that can be regarded as "critical" to skilled performance (Sukop, 1978).

The Research Questions nalysis of these two gymnasts was undertaken to reso lve two principal questions . (a) Did Gymnast A use a larger range of motion in the spine and nearby related joints than Gymnast B during the hand

Technique

contact phase of the flip flop? Gymnast A had sustained two spinal stress fractures prior to coming to Utah and spent the entire previous season resting her injury. We were interested to see if the hyperextension of her spine and nearby joints are greater or equal to that of Gymnast B who demonstrates a more "typical" performance techn ique. We wanted to determine if Gymnast A was making herself more or less susceptible to further spine injury as a result of hyperextension of her spine. (b) What technique differences did Gymnast A display relative to Gymnast B? Question (b) will be considered in part two of this project. Even though Gymnast A was injured the previous year her take off is very powerful. Gymnast B demonstrates a competent take off but not the same power, quckness, and streched body positions as Gymnast A. We would like to see what Gymnast A is doing differently from Gymnast B so that perhaps we cou ld model Gymnast B's technique more along the lines of Gymnast A. Also, Gymnast B was suffering from achilles tendonitis and we were curious if there was any technical differences between the performers at the ankle joint specifically.

Results and Discussion ack injury considerations . The stick figure graphics of gymnasts A and B during the pre-hand contact phase are shown in Figures 1 and 2. Three frames were selected prior to the hand contact for comparison. Table 1 lists the acute ang les of the gymnasts in the spine and related jOints during each of these frames. The acute angles of the hips, torso , shoulders and neck are included in Charts 1 through 4. Tab le 1 shows that Gymnast A has 8 to 10 degrees less hyperextension at the hip than Gymnast B. The torso shows 1-2 degrees less hyperextension for Gymnast A and the shoulder of Gymnast A shows 4 to 8 degrees greater flexion . (Refer to Research Detour 3). The neck of Gymnast A showed the greatest difference of all the joints with 31 to 37 degrees less hyperextension than Gymnast B. All of these jOints angles would appear to allow Gymnast A to move her spine and related joints through a less extreme range of motion to compromise her spine. The increased shoulder flexion of Gymnast A may be the result of attempting to reach the floor earlier in the descent to her hands without forcing a hyperextension in her spine.

FIGURE 1

SUBJECT

PHASE IN THIS DISPLAY = PREHAND CONT FRAMES IN THIS DISPLAY ARE 1 TO 4 TIME DURATION = .05 SECONDS SCALING FACTOR = 1 Comparison Of Subject A and Dill. Subject B B A Subject = = = HyperExt HIP Less 145 8 Frame No.2 153 Less 145 10 3 155 HyperExt TORSO 1 Less 133 Frame No.2 134 Less 134 2 136 3 Flexion SHOULDER More 170 8 Frame No.2 178 More 171 4 175 3 HyperExt NECK 37 Less 126 Frame No.2 163 131 31 Less 162 3 All frames show that Subject A is using less extremes in range of motion with the exception of shoulder flexion which shows that Subject A is using more shoulder flexion during this phase of the skill. Table 1

Pre-Hand Contact Phase Degrees

BIOMECHANICS JOINT ANGULAR MOVEMENT GRAPH ANGLE OF JOINT IN DEGREES PER FRAME <= =FRAMES TIME= = ,

180 omREES

135 DIDREES

II I

.. r

I I I I I

I t I I

Stl'B.JECT

I L II II It II II I I

1 \

90 DIDRBES

\I I. \I ' \I . \I "

Ie II

" ,." I.

,. \I

o omREES

1 2 3 4 5 6 7 8

DEGREES X 10 LEFT SIDE OF THE BODY PHASE PRE HANDCONTACT HAND CONTACT HAND DEPARTURE FOOT CONTACT HEEL CONTACT HEEL DEPARTURE FOOT DEPARTURE EOF

DmREES

CHART 1 FRAME NUMBER TIME DURATION .025 SECONDS 2 4 .0375 SECONDS 18 .175 SECONDS .15 SECONDS 30 .0375 SECONDS 33 .025 SECONDS 35 .0625 SECONDS 40 .2625 SECONDS 61 62 .0125 SECONDS

BIOMECHANICS JOINT ANGULAR MOVEMENT GRAPH ANGLE OF JOINT IN DEGREES PER FRAME FRAMES :TIME

l ao DIDREES

ang le of Gymnast A during hand contact of 167.40 degrees and the mean ang le of Gymnast B during the same phase was 152.20 degrees. The results in Table 2 also show that Gymnast A straightens her hip angle or finishes the flexion at the hip sl ightly sooner than Gymnast B. The torso of Gymnast A does not follow the same comparative pattern during the hand contact phase as that of the pre-hand contact phase . The torso of Gymnast A shows slightly more hyperextension than Gymnast B from o to 5 degrees with a mean of 1.36 degrees. Both gymnasts reach nearly 180 degrees by completion of the hand contact phase but Gymnast A shows slightly more hyperextension of the torso during frames 7 through 10. This does not seem to offer Gymnast A protection against extremes of range of motion but the small differences will require further research to determine their influence. The greater torso hyperextension of Gymnast A during hand contact may be the resu lt of her slightly higher flip flop and the concom itant necessity for absorbing this force through joint action during the hand contact phase . This seems to be intiuitively obvious by also looking at the increase of shoulder extens ion (cushioning bend) during the hand contact phase of Gymnast A (Refer to Research Detour 3) .

Research Detour 3 The movement of the shoulder is somewhat confusing to describe. Raising the arms forward and upward from the sides of the body to overhead is called anatomical "flexion." This seems strange because we usually call this "opening" the shoulder angle and its hard to consider opening the angle as flexion. The flexion action comes from a need to be consistent among the limbs of the body. The flexion of the leg is considered moving the leg from the hip upward and forward, when the arm is raised in similar motion this is also called flexion. So, if you get confused just imagine the same movement of the leg from the hip, t he arm motion will receive the same name. PHASE IN THIS DISPLAY = HAND CONTACT FRAMES IN THIS DISPLAY ARE 4 TO 18 TIME DURATION = .1875 SECONDS SCALING FACTOR

()

FIGURE 3

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1\ 1\ \I \I 1\ \I \I

1 2 3 4 5 6 7 8

rSHOU1JlEl1.

DEGREES 10 LEFT SIDE OF THE BODY PHASE PREHAND CONT HAND CONT HAND DEPART FOOT CONTACT HEEL CONT HEEL DEPART FOOT DEPART EOF

SUBJECT

1.5 DIDREES

DEGREES

CHART 2 FRAME NUMBER TIME DURATION .025 SECONDS 2 .0375 SECONDS 4 18 .175 SECONDS 28 .125 SECONDS 30 .025 SECONDS .05 SECONDS 34 .0625 SECONDS 39 .3 SECONDS 63 64 .0125 SECONDS

The hand contact phase of the flip flop is shown in figures 3 and 4. The duration of the hand contact phase is identical for both gymnasts at .1875 sec. or 14 frames. Note that the last frame of the preceding phase and the first frame of the succeeding phase are included for clarity of transition from phase to phase. Table 2 shows the ang les of the spine and related joints for both gymnasts. Gymnast A shows less hyperextension at the hip, 12 to 20 degrees. The mean difference for the hip ang les of gymnasts A and B is 14.60 degrees with the mean hip

FIGURE 4

SUBJECT B

Again, the neck angles of the two gymnasts showed large differences. The neck angle differences between the two gymnasts ranged from 6 to 36 degrees with a mean difference of 23.70 degrees. The mean ang les of the neck were 175.80 and 152.10 for gymnasts A and B respectively. Charts 1 through 4 indicate these relationsh ips in graphic format. The areas of the charts for our consideration are shown bounded by vertical dashed li nes. Each area represents a phase as defined by the numbered legend below the chart . You can see the relative differences of the two gymnasts by comparing the locations of the lines and phases for each athlete.

Technique

Joint-' Subj.- , Frm No.

4 5 6 7 8 9 10 11 12 13 14 15 16 17

158 160 164 167 168 170 170 172 178

Table 2 Hand Contact Phase All Numbers in Degrees HIP TORSO SHOULDER B Ditt. A B Ditt. A B Ditt.

146 147 150 151 153 154 155 156 158

135 136 137 141 143 145 148 150 153 158 163 168 173 179 167.4 15.22 152.1 152.2 150.7

Ave . Ave.

12 13 14 16 15 16 15 16 20

137 138 137 137 138 140 144 148 152 157 163 167 173 179

2 2 0 -4 - 5 - 5 - 4 - 2 - 1 - 1 0 - 1 0 0

170 163 155 148 140 135 134 133 132 133 135 136 139 142 142.5 - 1.36

BIOMECHANICS JOINT ANGULAR MOVEMENT GRAPH ANGLE OF JOINT IN DEGREES PER FRAME FRAMES:TIME

NECK B Ditt.

171 168 164 160 154 148 144 141 139 139 140 141 144 146

- 1 164 135 - 5 165 136 - 9 170 137 - 12 176 141 - 14 179 143 - 13 179 145 - 10 177 148 - 8 177 150 - 7 179 153 - 6 179 158 - 5 179 163 - 5 179 168 - 5 179 173 - 4 179 179 - 7.43 152.1 149.9 175.8

29 29 33 35 36 34 29 27 26 21 16 11 6 0

80 DEGREES

115 DEGREES ,

SUBJEd'

I I

DEGREES

I" I II

23.7

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路Subject A begins the hip flexion phase earlier than Subject B so that further comparison would not be warranted . After this point one would be comparing extension anqles with flexion angles.

The inability of this type of analysis to directly determine the Internal forces , shears , compressions, etc. on the spine of the athlete makes all of the above simply educated estimations of possible effects. It appears from the data that Gymnast A has managed to limit the range of motion of her spine through the latter portions of the flip flop and hand contact phases at least in comparison with Gymnast B. The only disagreement from th is line of thinking in the data comes from analysis of the torso angle where Gymnast A shows slightly greater torso hyperextension than Gymnast B. Overall though , the data seems to indicate that Gymnast A has adapted some movements during the skill to protect her lower back from extreme ranges of motion. Although Gymnast A has learned this compensation Clui~e on her own, it may help to prolong her training longevity In gymnastics.

, I

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I I II

1 2 3 4 5 6 7 8

DEGREES x 10 LEFT SIDE OF THE BODY PHASE PREHAND CONT HAND CONT HAND DEPART FOOT CONTACT HEEL CONT HEEL DEPART FOOT DEPART EOF

DEGREES

CHART 4 FRAME NUMBER TIME DURATION .025 SECONDS 2 .0375 SECONDS 4 .1 75 SECONDS 18 .125 SECONDS 28 .025 SECONDS 30 .05 SECONDS 34 .0625 SECONDS 39 .3 ECONDS 63 .0125 SECONDS 64

Part II

BIOMECHANICS JOINT ANGULAR MOVEMENT GRAPH ANGLE OF JOINT IN DEGREES PER FRAME FRAMES:TIME

Take Off Mechanics

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DEGREES x 10 LEFT SIDE OF THE BODY PHASE PRE HANDCONTACT HAND CONTACT HAND DEPARTURE FOOT CONTACT HEEL CONTACT HEEL DEPARTURE FOOT DEPARTURE EOF

Technique

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DEGREES

CHART 3 FRAME NUMBER TIME DURATION .025 SECONDS 2 .0375 SECONDS 4 .175 SECONDS 18 .15 SECONDS 30 .0375 SECONDS 33 .025 SECONDS 35 40 .0625 SECONDS 61 .2625 SECONDS 62 .0125 SECONDS

he second portion of this research report consists of the question of the differences the two ath letes display in their take off mechanics. We would like to know what the differences are so that perhaps we can discover some reasons behind Gymnast A's powerful take off and Gymnast B's achilles tendon problems. Even though Gymnast A has a back injury she also has one of the most powerful somersau lts this investigator has ever seen. The following will attempt to define and describe some of these differences. Determin ing these types of differences may help us decide wh ich parts of the take off technique are critical for exemplary execution. Figures 5 and 6 show the gymnasts during the snap down phase. Both gymnasts alter the paths of their feet during the last four frames of the snap down . Note that Gymnast A begins her extension of the hip prior to foot contact slightly earlier than Gymnast B. Figures 7 and 8 show the gymnasts during these last four frames prior to foot contact with the resultant velocity vectors drawn from the body landmarks. (Refer to Research Detour 4) . You should note that through all four frames prior to foot contact that Gymnast A has a steeper descent of the center of mass (COM) and that the vectors of Gymnast B's lower body are more forward directed than Gymnast A. Further, the lower body vectors of Gymnast A are generally shorter than her upper body vectors wh ile Gymnast B shows the opposite . The upper body vectors of Gymnast B are more forward directed than Gymnast A. In short, this means that Gymnast A's upper body is moving upward and backward at a higher speed than Gymnast B. This should assist Gymnast A in "getting through " the foot contact portions of take off more quickly than Gymnast B and with a more stretched body position.

PHASE IN TH IS DISPLAY = HAND DEPARTURE FRAMES IN THIS DISPLAY ARE 18 TO 30 TIME DURATION = .1625 SECONDS SCALING FACTOR = 1 SUBJECT A

FOUR FRAMES PRIOR TO FOOT CONTACT FIGURE 8 SUBJECT B

() FRAME = 24 PHASE = HAND DEPART THETA OF COM = - 4.08586 DEGRESS VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

PHASE IN THIS DISPLAY = HAND DEPART FRAMES IN THIS DISPLAY ARE 18 TO 28 TIME DURATION = .1375 SECONDS SCALING FACTOR

SUBJECT B

FRAME = 25 PHASE = HAND DEPART THETA OF COM = - 7.85388 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FOUR FRAMES PRIOR TO FOOT CO NT ACT FIGURE 7 SUBJECT FRAME = 26 PHASE = HAND DEPART THETA OF COM = - 9.7823 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY FRAME = 26 PHASE = HAND DEPARTURE THETA OF COM = - 11.685 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 27 PHASE = HAND DEPART THETA OF COM = - 9.46200 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 27 PHASE = HAND DEPARTURE THETA OF COM = - 14.9284 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 28 PHASE = HAND DEPARTURE THETA OF COM = - 16.7891 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 29 PHASE = HAND DEPARTURE THETA OF COM = - 18.1988 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

Research Detour 4 Forces, velocities, and accelerations, are all vector quantities which means that they have magnitude AND direction. The velocity of a body (or a body part in this case) can be described by its magnitude and its direction. We can determine that magnitude of the speed of the movement by measuring how far it moved in an interval of time. The vectors drawn by the computer represent the direction of the movement of each body part and the velocity is represented by the length of the vector. We can determine the direction of the movement of the body by using the x and y coordinates from the digitizing. For example, a foot may move from point L to point M during the skill as defined by our digitized map of the movement from 2 frames of film. As shown below the actual movement was a diagonal line but we can define the new location by measuring how far the foot moved in X (horizontal) coordinate units and in Y (vertical) coordinate units. We can also measure the angle of the movement from the horizontal by measuring from the X line or from vertical by measuring the Y line.

Technique

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achilles tendonitis during these tumbling take offs. It appears intuitively plausible that Gymnast 8's greater de:Pth of ankle dorsiflexion may be partially responsible for thiS tendon problem. Therefore , we might want to model Gymnast 8's take off mechanics more after those of Gymnast A. PHASES OF TAKE-OFF FIGURE 9 SUBJECT

(L - - - - - - - - - - - - - - - - - - - - -

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x Coordinate Direction

By using some vector arithmetic we can determine a few new things. We know the velocity = distance / time so if we want to know the horizontal component of velocity we simply need to determine the distance traveled horizontally and the time it took to get there. If we want to know the vertical velocity component then we can simply do the same thing with the vertical distance and time. By deriving some formulas in trigonometry we can tell the angle of movement, the vertical component velocity, the horizontal component velocity, the resultant of the two components, and the angle of the movement. The resultant is the "result" of the interaction of the horizontal and vertical components. The interactions of all these components are given in the formulas below. Vup = Vres * (Sine of Angle A) Vhor = Vres â&#x20AC;˘ (Cosine of Angle A) Where: Vup = Vertical Component Velocity Vhor = Horizontal Component Velocity Vres = Resultant Velocity Angle A = Angle of direction of movement from the horizontal usually called Theta. As mentioned above you can use these simple formulas on our digitized map of the motion for acceleration and for forces since all are vector quantities. The computer performs these calculations for every body part and for every frame by comparing each position with its previous and succeeding frames to calculate the distance traversed and the amount of time between frames tells how long it took to get there. Figures 9 and 10 show the stick figures of all the frames of each portion of the take off phase. Figures 11 and 12 depict the first frames of each take off phase and the resultant velocity vectors (Refer to Research Detour 4) . The figures listed above along with Table 3 show that Gymnast 8 is on the floor longer than Gymnast A, and in particular, Gymnast 8 is on her heels longer than Gymnast A. This longer time period on the floor may be the result of inefficient movements prior to the foot contact. As you might notice in Figures 5 and 6 Gymnast 8 is leaning much farther forward at the end of the snap down than Gymnast A and that she is more piked at the hips than Gymnast A. These actions may compel Gymnast 8 to "wait" for her upper body to get over her feet so that she can leave the floor at vertical. It appears that Gymnast A's ability to get through the take off phase quickly is an advantage, also that her ability to begin the take off actions with a more vertical orientation and stretch of the body are helpful. The angles of the knee and ankle joints observed during the take off phase are shown in Charts 5 and 6. It is interesting that Gymnast A shows less ankle dorsiflexion and more knee flexion during the take off than Gymnast 8. This is interesting due to the fact that during the training season Gymnast 8 had some significant problems with

Technique

FRAMES 35-40 HEEL DEPARTURE TO FOOT DEPARTURE

FRAMES 33-35

FRAMES 30-33

HEEL CONTACT TO HEEL DEPARTURE

FOOT CONTACT TO HEEL CONTACT

PHASES OF TAKE-OFF FIGURE 10 SUBJECT

FRAMES 34-39 HEEL DEPARTURE TO FOOT DEPARTURE

FRAMES 30-34 HEEL CONTACT TO HEEL DEPARTURE

FRAMES 28-30 FOOT CONTACT TO HEEL CONTACT

Table 3

Time Distribution During Take-Off (Frames) Subject = = =, A (Frames) B Seconds Seconds Foot Contact to Heel Contact .0375 3 .025 2 Heel Contact to Heel Depart. .025 .05 4 Heel Depart. to Foot Depart. .0625 5 .0625 5 .1375 11 Totals .125 10

Table 4

Subject Frame No. 30 31 32 Subject Frame No. 33 34

Vertical Component Accelerations Of the Center of Mass Meters/Sec/Sec Foot Contact to Heel Contact B A 23.8 Frame No. 28 23.9 38 .1 43.0 29 66.9 Heel Contact to Heel Departure B A 47.6 Frame No. 30 71.6 31 57.1 57.3 57.1 32 52.4 33

Peak accelerations are shown to be greater in Subject A than in Subject B.

FIRST FRAMES OF EACH TAKE-OFF PHASE FIGURE 11 SUBJ ECT A

FRAME = 34 PHASE = HEEL DEPART THETA OF COM = 53.471 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 30 PHASE = FOOT CONTACT THETA OF COM = - 13.1371 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY FRAME = 39 PHASE = FOOT DEPART THETA OF COM = 58.171 9 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 33 PHASE = HEEL CONTACT THETA OF COM = 21 .8014 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY BIOMECHANICS JOINT ANGULAR MOVEMENT GRAPH ANGLE OF JOINT IN DEGREES PER FRAME FRAMES:TIME

180 DroRUS

DECREES

FRAME = 35 PHASE = HEEL DEPARTURE THETA OF COM = 45 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY II II

I I II II

I I II

FRAME = 40 PHASE = FOOT DEPARTURE THETA OF COM = 55.4031 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FIRST FRAMES OF EACH TAKE-OFF PHASE FIGURE 12 SUBJECT B

FRAME = 28 PHASE = FOOT CONTACT THETA OF COM = -7. 59507 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

FRAME = 30 PHASE = HEEL CONT THETA OF COM = 8 .13059 DEGREES VECTORS SHOWN ON THE LEFT SIDE OF THE BODY

1 2 3 4 5 6 7 8

DEGREE S x 10 LEFT SIDE OF THE BODY PHASE PRE HANDCONTACT HAND CONTACT HAND DEPARTURE FOOT CONTACT HEEL CONTACT HEEL DEPARTURE FOOT DEPARTURE EOF

DECREES

CHART 5 FRAME NUMBER TIME DURATION 2 .025 SECONDS 4 .025 SECONDS 18 .175 SECONDS 30 .15 SECON DS 33 .0375 SECONDS 35 .025 SECONDS 40 .0625 SECONDS 61 .2625 SECONDS 62 .0 125 SECONDS

Charts 7 and 8 show horizontal and vertical component velocities of the gymnasts. These indicate that Gymnast A is descending faster than B prior to and during foot contact. Both gymnasts show the center of mass rising about half-way through the foot contact phase and peak vertical velocity is attained by both gymnasts slightly after heel departure. Gymnast A shows a slightly steeper rise of the vertical component which indicates that the vertical acceleration of Gymnast A is greater than Gymnast B. The vertical component acce lerations of the center of mass are shown for foot contact and heel contact in Table 4. Peak accelerations are attained slightly before heel departure whi le peak vertical velocities are reached slightly after heel departure. The peak vertical velocity of Gymnast A is 3.6 meters per second and Subject B is 3.7 meters per second. Interestingly, the biggest difference between the two gymnasts is not in the vertical component. The horizontal components show a decrease in velocity in the horizontal direction for both gymnasts. However, Gymnast A shows less of a decrease in horizontal velocity than

Technique

BIOMECHANICS JOINT ANGULAR MOVEMENT GRAPH ANGLE OF JOINT IN DEGREES PER FRAME FRAMES:TIME

SUBJECT

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CHART 6 FRAME NUMBER TIME DURATION 2 .025 SECONDS 4 .025 SECONDS 18 .175 SECONDS 28 .125 SECONDS 30 .025 SECONDS 34 .05 SECONDS 39 .0625 SECONDS 63 .3 SECONDS 64 .01 25 SECONDS

BIOMECHANICS HORIZONTAL AND VERTICAL COMPONENT GRAPH VELOCITY OF BODY PART MOVEMENT IN METERS/SECOND

SUBJEC~

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Gymnast B. Gymnast A slows to 2.5 meters per second while Gymnast B slows to 2.1 meters per second. Again, this may have been caused by Gymnast B's larger forward lean at foot contact and thereby a necessarily longer time penod to get her body to a vertical position, requiring more force and thus borrowing some force from her somersault actions.

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DEGREES x 10 LEFT SIDE OF THE BODY PHASE PREHAND CO NT HAND CONT HAND DEPART FOOT CONTACT HEEL CO NT HEEL DEPART FOOT DEPART EOF

BIOMECHANICS HORIZONTAL AND VERTICAL COMPONENT GRAPH VELOCITY OF BODY PART MOVEMENT IN METERS/SECOND

DIRECTION VERTICAL COMPON ENT.026DOWN HORIZONTAL CO MPONENT.026LEFTLEFT SIDE OF THE BODY BODY PART PHAS E FRAME NUMBER .026 PRE HANDCONTACT 2 .025 SECOND S HAND CONTACT 4 .025 SECOND S HAND DEPARTURE 18 .175 SECONDS FOOT CONTACT 30 .15 SECONDS HEEL CONTACT 33 .0375 SECONDS HEEL DEPARTURE 35 .025 SECONDS FOOT DEPARTURE 40 .0625 SECO NDS 60 .25 SECON DS

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DIRECTION LEFT SIDE OF THE BODY PHASE 1 PREHAND CONT 2 HAND CONT 18 28 30 34 39 62

11 11

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HORIZONTAL COMPONENT.026LEFT VERTICAL COMPONENT.026DOWN BODY PART .026 CENTER OF MASS FRAME NUMBER TIME DURATION 2 .025 SECONDS 4 .025 SECONDS 3 HAND DEPART .175 SECONDS 4 FOOT CONTACT .125 SECONDS 5 HEEL CONT .025 SECONDS 6 HEEL DEPART .05 SECONDS 7 FOOT DEPART .0625 SECONDS .2875 SECONDS

Conclusion e can gather some evidence from this research to help us design teaching methods more confidently and , help the two gymnasts in particular. First, peak acceleration for both gymnasts was attained earlier than I had suspected. This indicates that the pre-take off actions are more critical since there is very little time during foot contact to develop the take off forces . Second , directing the learning process of the take off should include drills and information concerning an emphasis on getting the upper body up during the snap down. It appears that the faster the gymnast moves the upper body over the feet during take off and the more stretched the body can remain the more effective the take off. Therefore , the snap down should not simply emphasize getting the feet down quickly but also should emphasize getting the upper body up quickly. Third , Gymnast B should begin drilling these concepts in earnest so that symptoms of her achilles tendon itis might be relieved . Fourth , Gymnast B should cut down on her repetitions of the tumbling take off until the technique improves, the pain is gone, or both. Since undertaking this study we now have some 20-20 hindsight in which to see whether the analysis was correct. The back problems were a nuisance throughout the year for Gymnast A but never incapacitating. The technique adaptations in tumbling seemed to be quite appropriate for her safety. Checkups with the doctor during and after the season indicated that no further harm was being done. Gymnast B's take off mechanics were attacked by reducing repetitions and encouraging a better push from the shoulders during the snap down . An anti-inflammatory was used to help reduce the symptoms of the achilles tendonitis and an ankle strap provided to prevent extreme dorsiflexion during landings and take offs. Symptoms were reduced and then ultimately removed prior to the end of the season. Gymnast B's tumbling improved to the point of being one of the team 's most consistent on skills such as her double back.

References Asu mussen. E.• Jorgensen. K. (Ed.). (1978) . Biomechanics VI-A. 2A. Balti more Maryland : University Park Press. George. G. S. (1980) . Biomechanics of Women's Gymnastics. Englewood CliHs, NJ: Prentice Hall. Hay, J. G. (1973). The Biomechanics of Sports Techniques, Englewood CliHs, NJ : Prentice Hall. Hochmuth, G., Marhold, H. (1978). Th e further development of biomechanical principles. In Asmusse n, E. Jorgensen, K. (Ed.), Biomechanics, VI-B, (pp. 95). Baltimore, MD : University Park Press . LeVeau, B. (1977) . Biomechanics of Human Motion , (2nd Ed.) , Philadelphia, PA: W. B. Saunders Company Plagenhoef, S. (1971) . Pattern s of Human Motion : A Cinematographical Anlaysis. (pp. 18-27). Englewood CliHs, NJ: Prentice Hall.