It's summertime and the weather is heating up. Soon you will be forced to take measures to avoid training in excessive heat, such as moving workouts from the middle of the day to the early morning or evening and transferring outdoor workouts indoors.
Not only is training in excessive heat uncomfortable, after all, but it also slows you down and thus doles out a smaller fitness benefit.
Or does it? Actually, new research suggests that training in the heat may be more beneficial for fitness than doing equivalent training in cooler weather. So instead of doing everything you can to avoid exercising in the heat this summer, you may want to use it (carefully) to your advantage.
The idea that suffering through a one-hour run or a two-hour bike ride on a 100-degree day could be more beneficial than doing the same workout in greater comfort and faster in 55 degrees may seem crazy. But there are other methods, including altitude training, that are known to enhance the effectiveness of exercise by making it more difficult. Heat training has the potential to boost fitness in a parallel way; however, like altitude training, heat training is not something you'd want to do all the time.
The proof of heat training's effectiveness comes mainly from research conducted by Santiago Lorenzo at the University of Oregon. In 2010 Lorenzo recruited 20 highly trained cyclists and had them complete a performance test in temperate conditions on two occasions separated by 10 days. Between the tests, all 20 cyclists completed a prescribed training program, but 12 of them did it in a controlled, hot environment (100 degrees) while the other eight performed their workouts in temperate conditions (55 degrees) matching those of the performance tests.
The 12 cyclists who underwent heat acclimatization improved their performance in the cool performance test by 6 percent. In addition, their VO2max and their power output at lactate threshold increased by 5 percent. There were no improvements among those who trained in a cool environment.