What is the best moment of the day to skate?
The influence of biological rhythms on performance
Only a few of us are really aware that our body and our health are governed by circadian rhythms, including our main organs. A circadian rhythm is a biological rhythm. It lasts about 24 jours, which more or less matches our everyday life. Phases of wakefulness alternate with phases of sleep.
Studies carried out on mice by the American researcher Christopher Collwel, a psychiatry professor at the University of Los Angeles (California), showed that physical effort affects our biological rhythms, and that the effects are positive if the physical effort takes place in the middle of the day.
Circadian rhythm disrupting elements
Our biological clock may be turned upside down by many factors:
- time difference
- food (too fatty)
- old age
For example, artificial light in the evening may disrupt your internal clock which should prepare for the sleep phase. Television or computer screens are well-known disrupting factors.
With age, falling asleep at night and sleeping soundly becomes more and more difficult. And the day after, it may be hard to stay awake.
What are the effects of disrupted rhythms?
Desynchronizing circadian rhythms may have many consequences on your health:
- increased risks of diabetes
- increased risks of obesity
- increased risks of certain types of cancers
- increased risks of memory loss
- increased risks of mood disturbance
- increased risks of depression
Note: teenagers naturally tend to go to sleep late and wake up late. That tendency reverses with age.
Could physical effort have beneficial effects on circadian rhythms?
Dr. Colwell's studies and those of his colleagues show that physical activity may help "fixing" the internal clock. Regular exercise helps for the biological clock timing.
At what hour should I do sport?
It would seem that physical activity in the afternoon has even more beneficial effects on health. That record surprised researchers who were expecting that morning exercise would have greater effects, just as most sportspeople and trainers often think.
The diagram below shows that coordination, reaction speed, efficiency and muscle strength reach their peak between 2:30PM and 5PM. Given that the sum of these factors influences sport performance, let's venture the hypothesis that it is the best time to practice physical activity in competition.
Note: pain tolerance is also higher by the end of the afternoon.
At what hour should I avoid doing sport?
At midday after lunch, your body mobilizes its resources for digestion. The stomach and intestines are working. Thus, the oxygen available for the other organs reduces.
If the meal was generous, the sensation of sleep is even bigger, especially because your brain would get less oxygen too. Useless to say that your performances will not be successful!
In that case, better not fight and have a 15 min nap to recharge your batteries for the whole afternoon!
As soon as 9PM, your body starts to exude melatonin (also called "sleep hormone") from serotonin. In other words, you body gets ready to sleep. It is exuded by the pineal gland (in the brain) in response to the lack of light. Then, it is better not to expose yourself to light after 9PM or have a physical activity. It is also when your body temperature starts to reduce.
From 10:30PM, the human body's functions go into sleep mode, the intestines stop moving, the vasopressin suppresses the sensation of thirst.
Practicing sport in the late hour (11PM for example) is not recommended. Studies on mice showed that they experience significant disruptions in their circadian rhythms, and even insomnia.
Between 2AM and 4AM, sleep is at its deepest and your body temperature drops. Doing sport in that time slot puts your body to a severe test.
You will have to wait 7:30PM for the production of sleep hormone to stop, almost 10 hours after it started.
If you have to do sport in the morning, your body will be more likely to resist between 9AM and 11AM.
Generally speaking, practicing a physical activity has positive consequences on your body and its rhythms, whatever the time of day (but not at night). That effect will be increased if you do sport in the afternoon. However, be careful not to do sport too late or you may disrupt your biological clock.
Body planning (source: wikipedia)
Translation: Chloé Seyres
Photos: rollerenligne.com, Mantroll, Wikipedia