With new recommendations, a panel of experts aims to help athletes compete in hot environments.
Many major sporting events take place in the summer, including the Summer Olympics, the FIFA World Cup and the Tour de France.
“Our motivation was to offer recommendations on how to best protect the health of the athlete and sustain/enhance performance during events taking place in the heat," Andreas Flouris, who helped write the new guidelines, told Reuters Health in an email.
"These guidelines represent the state-of-the-art for training and competing in the heat and should be followed by athletes, coaches, and event organizers," said Flouris, an assistant professor in physiology at the University of Thessaly in Greece.
Flouris and other experts in sports medicine and physiology met recently in Qatar, where the 2022 FIFA World Cup is to be held, to discuss training and competing in the heat.
In Qatar, daytime summer temperatures regularly surpass 40 degrees Celsius (104 F).
What's more, exercise generates large amounts of heat in the body and if this heat is not released into the environment, the athlete's body temperature will rise, which can reduce performance and cause serious health risks.
And in hot environments, it is more difficult for heat to be released from the body, Flouris noted.
One important factor for athletes is heat acclimatization, or the process of adapting the body to the environment in the time before competition.
Body functions such as heart rate and internal temperature will adapt after one week of training in the heat, but the experts recommend two weeks as an ideal adjustment period.
Athletes can adapt to the heat by arriving at the competition's location early to train. Or, they can train in artificially heated environments for an hour per day.
"Acclimatization can decrease the risk of heat illness, which includes symptoms like nausea, fatigue, fainting etc.," said Sven Voss, an exercise physiologist at Anti Doping Lab Qatar. He was not involved with the new recommendations.
In their June 11 online report in the British Journal of Sports Medicine, the experts also stress the importance of hydration and recommend that athletes drink fluid every two to three hours leading up to exercise.
Voss noted in an email that as a general rule, thirst is a good sign for an athlete to drink, but that under extreme conditions like ultra-marathons, it may be advisable to drink before signs of thirst occur.
The panel recommends taking plenty of fluids with meals and Flouris advised that recovery regimens should include sodium, carbohydrates and protein.
"Athletes training in the heat have higher daily sodium (i.e., salt) requirements than the general population," Flouris added. So they may need to take sodium supplements during exercise.
Lastly, the guidelines note that cooling down before, after or in-between events is an important consideration for athletes.
External cooling methods can include applying ice to the body, being immersed in water or fanning. Athletes can also use internal cooling methods such as drinking cold or icy fluids.
In addition to competitors' individual efforts, Flouris advised that event organizers and sporting federations can support athletes by "allowing additional (or longer) recovery periods for enhanced hydration and cooling opportunities."
"Try to find out beforehand how temperature, humidity, etc. will be at the place of competition and try to acclimatize," Voss recommended. "Make sure that you have a strategy when and how to drink according to your individual needs."
"Failing to prepare means preparing to fail, as heat can have deleterious effects on our health," Flouris said.
Source: Madeline Kennedy, June 26, 2015 http://www.medscape.com/viewarticle/846989