Sports training in the heat: dangerous or effective?

30 degrees in the shade, the sun is beating down on the field. The beach volleyball players at the university’s central sports facility in Munich’s Olympic Park lie exhausted on the lawn. Jan is studying sports science in the fourth semester. Playing in the heat stressed him: “You can’t do it anymore, your lungs burn, running becomes difficult, all the jumping and coordination, thinking becomes difficult later in the game, so it has an impact.

Above 25 degrees it becomes a problem for the body

Intense and hard sports training is a challenge for the body at these temperatures. And not everyone should jog, play tennis or football in the midday heat, says Karsten Köhler, professor of exercise, nutrition and health at the Technical University of Munich. Above 25 degrees it becomes a problem because the body has to work actively to dissipate the heat that is already created during exercise.

This means that the hotter it gets, the harder it is for the body to get rid of the heat. The pulse increases, the heart beats faster, the body temperature goes towards fever, and if tiredness and fatigue are added to this, these are clear warning signs: it leads to… Circulatory collapse or heat stroke come People with pre-existing conditions should be especially careful.

Heat can also increase performance

Under certain conditions, sports training in the heat can also be good. Norwegian researchers found this out in a study with professional cyclists. The athletes trained five times a week for 50 minutes in a heated room or in heated suits. After five weeks, the number of red blood cells had increased and with it the performance of the athletes. “When we train in heat, this means that the body has to provide its blood level in a different way,” explained the sports scientist Karsten Köhler.

It is only useful for professional athletes

Less blood goes into the muscles and more blood into the skin tissue, the skin becomes red, we sweat more. You bring the body to a different metabolic state, the same stress on the muscles becomes much more intense in the heat and you set a different training stimulus.

This means that you get two to three percent more performance, says Karsten Köhler. This can certainly make sense for professional athletes, but only if they are carefully monitored medically and the body temperature does not go too high. Everyone else should take it easy with the high temperature.

Drink a lot in the heat

If you still want to train, you should make sure that your body is prepared. So drink plenty beforehand. Clothing should be as breathable as possible so that sweat can evaporate quickly. If you are running for half an hour in the heat, you should take a drink with you. Water is enough for now. For longer training sessions, a sports drink also makes sense so that extra electrolytes can be added to the body.

And after exercise, everyone should cool down again, advises Karsten Köhler. In general, the question is always: Is it really necessary to move, play tennis and exercise in the midday heat? Or could it not be postponed until cooler hours in the morning or evening?