Performance in the heat

The Scandinavian Journal of Medicine and Science in Sports published a new consensus piece on training and competing in the heat that discusses practices for athletes, coaches, organizing bodies and event organizers.

 

The article makes it a point to say that the ‘most important intervention one can adopt to reduce physiological strain and optimize performance is to heat acclimatize.’ This is achieved through exercise in similarly hot climates to competition for 1-2 weeks, with more time necessary for less fit individuals. Exercise should be done for a minimum of 60 min to get proper acclimatization. It is not necessary for shorter duration activities to spend as much time training since their events are finished sooner. But, for longer duration activities in the heat, acclimatization is a must.

 

Prior to pre-season, athletes can work on adapting to the temperature by exercising on their own. This gives them the ability to go at their own pace in the weather they will be forced to exercise in once pre-season begins. The onus is on the athletes to take control of their fitness and lay the foundation prior to the season beginning.

 

In order to maintain thermoregulation, the body needs to have adequate hydration. Prior to exercise, the recommendation is to drink 6mL of water per kg of body mass every 2-3 hours as well as 2-3 hours prior to activity. Heavy sweaters can also supplement their hydration with salt to replenish sodium lost in sweat.

 

Once exercise is undertaken in the heat, time should be spent trying to cool off to prevent overheating. Different options are available and can be either internal via ingestible solutions or external. Internal strategies include drinking cold beverages and slushes while external involve cooling vests, fans or cold water immersion. A strategy that employs a combination of cooling mechanisms may be the most effective. It is important to note that these are for maintaining exercise and performance, but once an athlete shows signs of heat stroke the treatment is immediate cold water immersion and activation of the emergency response plan.

 

One of the potential risk factors for heat illness appears to be a recent viral infection that results in nausea, vomiting and diarrhea. Individuals that have experienced those symptoms may not have enough time to recover and rehydrate and thus be in greater danger of having a heat related illness. Warnings should be included in racing materials that warn athletes not to participate if that is the case. Event organizers can also adjust the start times of events to avoid the hottest part of the day and to allow for longer cooling and rehydrating between innings, matches or sets. These proactive efforts can give athletes the opportunity to recover out of the sun and heat and minimize chances for illness.

 

http://onlinelibrary.wiley.com/doi/10.1111/sms.12467/full