For some time we have wondered if training at a certain time of day would make a difference in performance at a race. We did some research to find answers to this question. In several studies, scientists have found that individuals tend to do slightly better on measures of physical performance, including endurance, strength output, and aerobic capacity, between 4pm and 7pm. The main reason is: body’s temperature and hormone levels peak in late afternoon, making muscle more flexible and producing the best ratio of testosterone. However the differences compared to people that train early in the morning or later in the day are very small.

Another interesting fact taken from several long-term studies is that the body tends to adapt to the time of day that you train, that is, if you train in the morning, your body will physically perform better in the morning, while if you train in the evening, you will perform better later on the day.

Out of the above, we can conclude the following: if due to your job or family obligations you can’t train between 4pm and 7pm, don’t stress yourself, accommodate your workout in anyway it fits your schedule; if you are training for a particular race (5k, 10k, half-marathon or even a marathon), you will have an advantage if you train at the same time of the race; most of the races are organized to start early on the day, so you are better off going for an early workout. And the final conclusion, regardless of the time of the day, any exercise is better than no exercise at all.

Partially taken from an article published in the Health section of the NY Times