Performance in endurance sports is determined by athletic preparation, determination and mental approach during exertion but also by some external factors. Among these, weather is definitely what you are confronted with on a daily basis. Hot, cold, rain, wind, and rough seas are situations you have to know how to deal with. The ability to react to these kinds of situations is part of your technical background as an athlete. Training means not only accomplishing the assigned task on a daily basis but also learning how to handle adverse situations without losing focus or even worse losing heart. In other words, you need to take care of a dedicated part in your workouts as well.
What happens when it is very hot?
Today we take a closer look at the weather situation that will be prevalent in the coming months: hot weather. What happens when temperatures rise? How can you defend yourself? If you have to face a competition in warm weather during times when you train in cold weather how should you prepare?
It is obvious that with high temperatures it becomes more difficult to sustain high intensity performance for a prolonged time. It applies to biking as well as running or team sports. What may be interesting is to understand the extent to which your performance drops in intensity or duration. For cycling, laboratory studies are less suitable for measuring this effect because while it is true that different temperatures can be reproduced, the effect of an important though little-known phenomenon is lost. A 20-degree C increase in ambient temperature (e.g., from 10 to 30 degrees) reduces air density by about 7 percent, allowing an increase of about 6 percent in the speed produced for the same power. So from an aerodynamic point of view in hot weather you gain something. Phenomenon that cannot be measured in the laboratory.
The test on Pro cyclists
In order to collect the data needed to assess the loss of performance in hot weather, a very interesting experiment was done. A group of top cyclists were made to repeat a time trial maximal testfour times over a distance of about 40km. The first time in Denmark with a temperature of about 10 degrees. The next in Qatar with temperatures above 35 degrees.
The results were really surprising. On the one hand as to be expected the first pedaling carried out in Qatar going from 10 to 36 degrees was very difficult. But the difference found is wider than expected. The average time increased from 66 to 77 minutes. It means that the loss of performance was 17%. Don’t be surprised when during the early warm weather your performance suddenly declines or even collapses. This is normal and not up to you. What is equally certain is that this loss of results is not likely to remain over time. In fact, after a few days in Qatar, the remaining two time trials were held: number three after a week of acclimatization and the fourth and final one two weeks after the second trial. The time obtained in the last trial was slightly less than that obtained in the first trial. The physical parameters measured in the cyclists were different. In the first cold test, the lowest average heart rate and highest average value in terms of power output was obtained. In a colder climate you are able to yield more in terms of results at a low internal load. The first experience in the heat was difficult. For a 17% loss in performance, there was a 4% increase in heart rate. So not only do you go slower but you also exert a lot more effort. In the last trial after two weeks of acclimatization, we had the same result in terms of duration as in the first trial in the face of a higher heart rate comparable to that in the second trial. The average power was slightly lower than in the first test. What is interesting is that with about 3 percent fewer watts and a higher heart rate you are able to perform better than in the cold. This happens precisely because in hot weather, as air density is reduced, aerodynamics improves, allowing you to maintain a higher speed.
What changes noticeably-and what you cannot manage with an acclimatization period-is your body temperature. After the first maximal test performed in the cold, the average internal body temperature was 38.5 degrees. At the end of the three tests conducted in the heat, the average temperature was always above 40 degrees. This difference has major consequences in terms of dehydration and especially health risks since it can lead to heat stroke, which is a major cause of withdrawal during endurance races held in the heat.
What does this analysis teach you?
- First of all that you should not be surprised by a drop in performance during the first few days when your body is exposed to significantly higher temperatures than when you have previously trained.
- Second, this drop in performance is temporary. It only takes you about fifteen days to get your body used to a new climate situation.
- While this is true, however, you should not overlook the fact that with high temperatures you have to cope with more strain, both actual and perceived. Pulse and body temperature rise much higher than similar performances made in a temperate climate.
- At the organizational level, this study suggests how you should move when you move to go to a race characterized by much higher temperatures. In theory you would need two weeks of acclimatization to get used to the new climate. When this is not possible, try to arrive as early as possible anyway to conduct a few training sessions with the sole purpose of acclimatization.
- Last but not least, there is one aspect that positively affects performance. If the temperature increases, your aerodynamics improve because you reduce the density of air and therefore the resistance you have to overcome as you move forward.
(main image credit: ljsphotography on DepositPhotos.com)