NUTRITION

Fad diets – beware low carbohydrate regimes

Gillian Woodward

It is that time of year again when you take off a few layers of winter clothing to expose your white flesh to the milder conditions. Are you disappointed that about the amount of extra flab hanging over the belt of your summer jeans? I hope you are not going to embark on one of the many fad diets that have pervaded the media, especially women’s magazines, in recent months.

One of the worst for athletes in training, or anyone who is active for that matter, has to be the high protein, low carbohydrate diet. Call it what you like – Atkins Diet Revolution, Sugar Busters, Scarsdale, Protein Power, Slim Forever – they all promote the same theme. Eat as much protein and fat as you can, but avoid carbohydrates at all costs.

We need carbohydrates

To a sports dietitian or exercise physiologist, this avoidance of carbohydrate goes completely against the grain. After all, carbohydrate is our major supply of readily available energy, being stored in the liver and muscles as glycogen. When these stores are depleted, we feel lethargic, fatigued and generally unable to exercise with the usual power. Our bodies need at least 100 g of carbohydrate per day (and much more if we are active) to stop us burning more valuable nutrients for a supply of glucose (like muscle protein). But athletes who train for an hour or two a day, need much more than this – more like 5-8 grams of carbohydrate per kilogram of body weight. For a 70 kg athlete, that amounts to at least 350-560 grams per day! A far cry from the 20-90 grams per day promoted by many of the high protein, low carbohydrate diets.

Side effects

Side effects of long term high protein diets can include fatigue, headaches, bad breath, loss of lean body mass (muscle tissue), constipation, nausea and ketosis. Losing muscle mass puts you at a particular disadvantage, as muscle burns energy at a much greater rate than fat. This is why when you go back to eating a more balanced diet, you can gain weight easily, because you now have a lower muscle to fat ratio.

If you do embark on a low carbohydrate diet, you are instructed to avoid or at least severely restrict most of the basic food groups. All bread and cereals, biscuits, pastas, rice, fruit, starchy vegetables (potato, corn, pumpkin, peas), legumes, milk, yoghurt and soymilk products are off limits. Also of course there would be no sugar, jam, honey, fruit juices, sports drinks or soft drinks of any kind allowed.

You are left with only meat, eggs, fats (butter, cream, margarine, oil), tea, coffee (without the milk or sugar of course) and some alcoholic drinks like wine and spirits. A few non-starchy vegetables like leafy greens, tomato, broccoli and cauliflower are also allowed. How boring, you might say! Even most of the fats are useless to you on this diet, as there is no bread or biscuits to put them on and no potatoes to fry in them!

You are so restricted in the foods allowed to be eaten, that you eat less overall for the day, ending up in energy deficit (consuming less kilojoules or calories than your body requires). This is how all successful weight loss diets work.

Certainly protein is satisfying to hunger. A large piece of rump steak or six slices of roast lamb will make you feel full. But it also provides you with excess protein that your body doesn’t need, so you have to break it down and get rid of the extra nitrogen via the kidneys, putting extra strain on them.

People do report quite fast weight loss on these diets (at least initially anyway). This is understandable, because without carbohydrates coming in via the diet, you deplete all your glycogen stores. With every gram of glycogen used up, 3-4 grams of water are also released. Losing 500 grams of glycogen thus results in the bathroom scales showing a 2 kg weight loss – very exciting at first. But this rate of weight loss is not maintained.

Studies on high protein diets, particularly the Atkins method, have shown that those who manage to stay on them for three months, can lose weight successfully in the short term, but at no greater rate in the long term than those on higher carbohydrate, lower fat, moderate protein weight loss regimes. The drop-out rate from high protein diets is also very high, due to the boredom/ restriction factor.

Nutritional concerns

What is more of a nutritional concern however, is the lack of certain vital nutrients on these diets. They are low in vitamins A, E, B6, folate, and thiamin. They also provide insufficient quantities of the minerals calcium and magnesium, as well as being deficient in fibre and potassium. The antioxidants and phytoestrogens are also missing. The diets are low in plant products which have been consistently shown to reduce risk of diseases like diabetes, heart disease, stroke, cancer, osteoporosis and bowel disease.

It is well known from research that after heavy exercise athletes can experience temporarily depressed immunity. Scientists refer to this as post exercise immunosuppression or PEIS. Studies have shown that in athletes who train with low glycogen levels after being on low carbohydrate diets for several days, there is a greater release of stress hormones compared to those who have had a higher carbohydrate diet. The more stress hormones released, the lower the immune function.

Consuming carbohydrates during exercise has also been shown to be beneficial in terms of reduced stress hormone release. Cyclists fed 30-60 grams of carbohydrate during two and a half hours of strenuous cycling did not show a drop in immune cells, unlike their counterparts who had no carbohydrate during the same exercise.

Carbohydrates are a valuable fuel and keep us healthy

So it seems that carbohydrates are not just important to provide a readily available fuel source to muscles, but also help to keep us healthy and avoid disease as well. So keep the carbs in your daily diet, but not in massive quantities, and avoid the ‘fast release’ or high GI and sugary foods (see article on GI in Autumn 2003 issue) if you need to shed kilograms. Base your diet on plant foods like vegetables and fruit, grainy cereals and breads. Have a little more protein rich foods if you like, but make sure they are low in (saturated) fat. Choose lean meats, skinless chicken, grilled fish and low fat milk, yoghurt, cottage or ricotta cheese as well as eggs.

Make sure that your new healthy ‘summer look’ eating regime is sustainable and is accompanied by plenty of daily exercise. Then you will be on a sure path to successfully fitting into those swimmers by the height of the season, and of course be able to compete at your peak in orienteering.

More specific guidelines in the December issue will help you to control your body weight in a sensible way.

Practise running on your compass

You may say: Of course I do know that the compass is always right. All the same I usually wind up too far left on compass runs, not so often too far right. What is the cause and how can I fix it? The compass needle always points to magnetic north unless there is some metal near the needle or some local magnetic anomaly in the terrain. Mistakes are usually due to how you use it. There are many causes - in the heat of competition we may fail to set the bearing accurately for the direction we want to go, or we don’t line the compass up accurately with the north lines on the map. Sometimes we do not allow the compass needle enough time to settle or in the forest we just glance at the compass and do not check the direction properly. If we are not using a thumb compass, but just put the compass on the map to determine which way to go, everything becomes even more uncertain. It’s difficult to try to read the compass while running; it’s just about impossible to hold the compass so it is completely still. Accurate compass running is not elementary and like everything else it needs to be practised. Many orienteers are not wholly confident in using the compass because they haven’t learned to use it correctly, that is they haven’t practised. Now and again it’s worthwhile training by running ‘from tree to tree’ to gain confidence in the technique and experience that it really works!

Some tips for compass running:

• On long compass runs it’s worthwhile taking extra care in the way you use the compass. Be especially careful with a thumb compass. • In aligning your compass, especially when you have the compass lined up on the map, don’t just turn your hand but your whole body, so that you are looking straight ahead in the correct direction. (Thinking “I need to go a bit to the right or a bit to the left” is always uncertain). • For a compass run in open terrain, stop still and aim for a distinct distant object, instead of running off and taking several quick looks at your compass. • So long as the bearing is correct, orienteering is relatively simple in complicated terrain too. It only becomes difficult if you don’t really know whether you are too far to the right or the left. (Abridged) Brigitte Wolf in OL (Switzerland). Printed with permission.

Brigitte Wolf winning Gold in the Relay at last year’s World Champs.

Vale – Hans Steinegger, 1948 - 2004

THE world orienteering community was saddened to hear of the sudden and untimely passing of Han Steinegger. Hans died from a heart attack after competing in a fun relay with club OLG Basel in Switzerland on Saturday 19 June 2004. Hans single-handedly revolutionised the drawing of orienteering maps with the development of OCAD software. From a small beginning as something of a hobby OCAD grew into the driving force behind the digital production of orienteering maps and a thriving business. Map drawing, which had previously been the preserve of a few skilled in the use of pen and ink on film, now became available to anyone with basic computer skills and a bit of enthusiasm thus spreading the map production load. In recent years OCAD has also played a significant role in the booming growth of maps for non-traditional forms of the sport such as Park & Street and Mountain Bike Orienteering. One of the outstanding qualities of OCAD software was how well it was written, and a package that offered so much and was adopted both within and outside the orienteering community, was compact, didn't demand huge computer resources and was priced to make it affordable to clubs and individual map makers. It was a great success story of programming where the needs of the users were foremost. We are thankful for the enormous contribution Hans made to our sport, and wish the remaining OCAD team every success in continuing to make Hans' vision a reality. He will be sadly missed by his colleagues and friends within the orienteering community, and our deepest sympathy goes to his partner, family and friends.

Noel Schoknecht

Maze Orienteering in Russia

TO make Orienteering a more attractive sport for spectators and for media, a club in Moscow has devised a new version of the sport, Maze Orienteering! A short course - running time about two minutes - is constructed of a maze of tapes secured to posts. In the corners there are control points, many more than the competitors are to visit. For example the course could be: Start - 9 – 10 – 11 – 12 and so on. The course can continue on a normal Orienteering map. This sort of Orienteering has proved to be exciting and attractive for spectators. At the first event in Moscow only 12 out of 38 starters punched all the maze controls correctly.

Azimut, Russia 2004/1