Does exercising in different temperatures have any effects on performance? Does cold weather cause more muscle cramping?
Thank you for the very interesting question. In fact, the more I researched this question, the more intriguing it got. When the question was first posed, it only made sense to me that there would be marked differences in performance based on the temperatures at which the athletes were asked to perform in. The reality is that the temperature had little or no effect on performance. There were many studies done with many different types of athletes. The best studies that we could find were done on Olympic cyclists. The findings of these studies showed that there were little if any variable effects on performance based on changes in temperatures.
Before delving into the studies themselves, we should look at the different physiological methods of heat dissipation by the body. The body will dissipate heat by radiation, conduction, convection and evaporation. Radiation of heat means that our body will give off heat if they are in an environment that is cooler. Radiation is the biggest way we lose heat in a normal environment. Conduction has to do with heat transfer directly from one object to another. In other words, if you were immersed in cold water your body would conduct heat to the cooler water. This method is not usually an issue unless you were in water or you had a large surface area of your body on something that was cooler. Convection is a measure of heat loss that deals mostly with wind or currents of air. The faster the current of air or wind, the cooler it is to our bodies, and the more heat that will dissipate. The last way to dissipate heat is through evaporation. Our sweat is produced and is released through the skin. The sweat is then evaporated in the air causing a cooling effect.
When the body is cold there will be a decrease in peripheral circulation. This decrease in circulation can cause a numbness or pain in the extremities. So, the answer is yes, it is more likely to cramp when performing in the colder weather. As far as in the heat, there would need to be more than one type of heat dissipation unavailable to affect the athlete in any way. When temperatures rise, the body is still able to dissipate heat through evaporation into the air by convection if you were running or biking, etc. The problems arise when there are no ways available to dissipate heat. When the temperature is above 98 degrees, the humidity is over 90 percent, there is no wind and you don’t have anything cool to put on you, there can be problems. The temperature is the same as your body, so radiation does not work effectively. High humidity in the air makes it difficult for the sweat to evaporate. The lack of wind cuts down on the convection and if there are no cool objects around it is challenging to dissipate the heat through conduction. This is when people can get seriously debilitated or even die. Although this situation can be dangerous, there were still no studies we could find that showed the athlete’s performance decreased at all. There were many studies showing that the athlete perceived him or herself as working harder when the temperatures had changed. This perceived exertion was not consistent with heart rate increases or performance issues.
In recap, temperature does not impede performance, but it can make athletes think they are working harder, and in extreme cases, it can make an event much more dangerous to the participants.
- Armstrong LE (1998). The induction and decay of heat acclimatization in trained athletes. Sports Medicine 12, 302-312.
- Hopkins W (2002) Little effect of training in the heat. Sport science 6, sportsci.org.