Recent studies have proven that there is an optimal time to exercise, says a BBC article. A few months before the important Olympic Games take place in our capital, it is time or never for athletes who want to make history to pay attention to this work. But even mere mortals like us may find the information useful.
At the Olympic Games in Athens 2004, Beijing 2008, London 2012 and Rio 2016, 144 medalists' times were better if they had competed at the end of the day. More specifically, around 5:12 p.m. This observation is part of a growing body of evidence that exercise performance is influenced by the time of day it is performed.
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The phenomenon doesn't just happen to Olympic medalists: we see that amateur cyclists who race against the clock are also faster at the end of the day. Resistance exercises are also particularly time-critical, with performance almost always peaking between 4 and 8 p.m. But how can it be explained?
The importance of circadian rhythms
The circadian rhythm, also known as the human body's internal clock, is at the heart of this phenomenon: a central clock in the hypothalamus responds to the effects of light via signals from the optic nerve. The suprachiasmatic nucleus then sends signals to peripheral clocks, other organs, muscles and fatty tissue, enabling the body to synchronize.
Juleen Zierath, an exercise physiologist at the Karolinska Institute in Sweden, has studied the connections between circadian rhythms and exercise. With her team, she found that the benefits of physical activity can be magnified depending on the time of day it is done. For example, women found that their performance improved when they performed an exercise in the evening compared to the same exercise session at a different time of day.
Thus, engaging in a physical activity at a specific time could maximize the health benefits of that exercise – particularly for people with metabolic diseases such as type 2 diabetes or obesity.
“Everyone agrees that it's good to exercise at any time of day, but we may be able to fine-tune the metabolic results of exercise depending on when we do it,” says Juleen Zierath.
“Reset” your internal clock
However, research in this area is still evolving, and some recent reviews of previous studies claim that the evidence is inconclusive. The main reason for this contradiction is simple: every person is unique. “There are differences in the timing of our clocks,” explains Karyn Esser, a physiologist at the University of Florida. Those of us who are larks probably have a clock that ticks a little less than twenty-four hours, and those of us who are owls probably have a clock that ticks a little more than twenty-four hours.”
But nothing is definitive: If you find that your circadian rhythm is not set the way you want, you can “reset” it. This is shown by the latest study by Karyn Esser's research group, which focused on mice. Initially, mice that performed them in the morning performed better than mice that performed them in the afternoon. After six weeks of training, both groups showed the same endurance performance.
The researchers therefore assume that if a similar effect occurs in humans, it would be possible for an athlete to “reset” their internal clock through appropriate training, simply by doing it regularly at the same time of day.
Remember that the majority of scientists believe that it is beneficial to exercise at any time. But if you find one that suits you better than another and stick with it, the results will be faster and more beneficial – both for your health and your athletic performance.