Feeling the heat
Photo: SHUTTERSTOCK/DGLimages
RESEARCH ROUND-UP
Post exercise passive heating has been identified as an effective way of building endurance, according to research by The American College of Exercise. Senior project manager at ACE, Daniel Green, talks us through the findings
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uilding endurance typically involves a combination of increased volume of training and steady state exercise and interval workouts, but this can lead to overtraining and injury. However, preliminary evidence has found exercise in conjunction with passive heat afterwards – such as hot water immersion – leads to endurancerelated benefits, including increased plasma volume and greater red blood cell mass. ACE enlisted the help of Lance Dalleck and his team of researchers in the High Altitude Exercise Physiology Programme at Western Colorado University to examine post exercise passive heating strategies. The team examined the impact of wearing a sauna suit and hot water immersion on VO2max, lactate threshold and exercise economy. The study involved 24 men and women, aged between 18 to 50, who
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Handbook 2021
were randomised into three groups. The control group performed exercise, but did not use either of the post-exercise passive heating strategies. One group used hot water immersion after exercise and the other group wore a sauna suit.
Hot tubs and sauna suits
At the start and end of the study, all participants performed a running test and their VO2max and lactate threshold was measured. All completed a three week, five day a week training programme, which involved three days of moderate intensity exercise (Monday, Wednesday and Friday), one HIIT session (Tuesday) and one steady state session at VT2 (Thursday). The two non-control groups underwent 30 minutes of passive heat recovery after every moderate intensity session: one group sat in a hot tub and the other group wore full-body sauna suits. Both groups
Hot tubs or saunas postexercise can lead to VO2 gains according to ACE
ingested core temperature sensors on two occasions during the heating protocols, to ensure they stayed below temperatures which might increase the risk of heat illness. After three weeks, mean VO2max changes and lactate threshold changes in the sauna suit and hot water immersion groups were significantly greater than the control group. However, only the hot water immersion group showed significant improvements in running economy between baseline and three weeks. In the control group, 50 per cent were categorised as VO2 responders meaning there was a greater than 3.2 www.HCMhandbook.com
