Sports science research: 5 of the latest news stories
James Witts shares the latest sports science research, including new thoughts on nutrition, fluid therapy and stretching
A tri hydration strategy is important for all athletes, and recent research suggests a regimented routine is far more effective than going freeflow. Ten elite cyclists rode a 30km criterium either drinking as much as they wished or drinking water every 1km to match predicted fluid losses. Performance improved significantly in the regimented group, thanks to favourable physiological measurements like lower body, skin and gastrointestinal temperature. The take-home message? A meticulous strategy will pay off, so set your HRM to remind you to drink at the races every 15mins or so.
STRETCH AND BURN
A comprehensive analysis of stretching literature by an Australian-UK team suggests that stretching offers no benefits, at least to the run segment. Acute stretching (like a warm-up), the authors concluded, can actually reduce run economy and performance for up to an hour by diminishing tendon stiffness, while chronic stretching (a long-term programme) also offers no performance advantage. It must be stressed, though, that this focused solely on running where your lower limbs could already be warm due to the act of walking.
According to respected nutritionist James Morton, there are just six supplements that have enough anecdotal and scientific evidence behind them for his recommendation. In no particular order, we have: carbohydrates, 60-90g per hour during training; caffeine, 2-3mg per kg bodyweight around 30-60mins before a race; 30g whey protein post-training and racing; 0.3mg per kg bodyweight of sodium bicarbonate 90mins prior to racing; vitamin-D supplement in the winter; and 3-6g of beta-alanine daily for four weeks to elevate muscle carnosine stores.
FREE YOUR MIND TO RACE FAST
A comprehensive meta-analysis has concluded, not surprisingly, that mental fatigue impairs endurance performance. The authors, including doctors Samuele Marcora and Romain Meeusen, highlighted that because mental fatigue doesn’t impact physiological markers of fatigue (heart rate or blood lactate) but is detrimental to performance output and raises rate of perceived exertion, those seeking to peak at the races should shy away from mentally taxing tasks in the build-up. The authors also showed that short, intense interval sessions are preferable over longer efforts.
HIGH FAT, LOW PERFORMANCE.
Dr Tim Noakes has courted controversy for usurping Dr Atkins as the flag-bearer for a low-carb, high-fat diet (LCHF). Though Noakes cites the nutritional strategy as vital for individuals who are insulin sensitive, he also espouses its benefits for athletes. Well, the good doctor might have to rethink his support for a high-fat triathlete diet after researchers investigated the effects of adaptation to a LCHF strategy during three weeks of intense training on metabolism and performance of world-class endurance athletes.
They noted that whole fat oxidation increased – favourable when training at a low intensity – as well as VO2 peak. However, oxygen cost increased, leading to a reduction in economy. This could be because the shifting of metabolism slowed down the movement from fat-burning to carb-burning when intensity rose. Instead of a high-fat diet, the researchers discussed the merits of playing around with carbohydrate intake depending on intensity and duration of session.