How important is circadian rhythms on sports performance?

Rhythm is linked to the light-dark cycle

by Lorenzo Ciotti
How important is circadian rhythms on sports performance?

Circadian rhythms are thought to have originated in protocells, with the aim of protecting DNA replication from high ultraviolet radiation during the day. As a result, replication took place in the dark. The Neurospora fungus, which still exists today, contains this regulatory mechanism.

The simplest known circadian clock is that of the prokaryotic cyanobacterium. Recent research has shown that the Synechococcus elongatus circadian clock can be reconstituted in vitro with just three central oscillator proteins.

This watch has been shown to sustain a rhythm of 22 hours for several days with the addition of ATP. Rhythm is linked to the light-dark cycle. Animals kept in total darkness for long periods operate at a freely regulating pace.

Each day their sleep cycle advances or regresses depending on whether their endogenous period is longer or shorter than 24 hours. The environmental stimuli that reset the rhythms every day are called Zeitgebers. Interestingly, totally underground mammals are capable of maintaining their internal clock in the absence of external stimuli.

Influence of circadian rhythms on sports performance, study published on the Chronobiology international, said us: "Chronobiology is the scientific discipline of study of biological rhythms, a term that has gained ground in the sports world.

Recently numerous studies have indicated that the time of day in which sports are practiced influences the achievement of good physical performance. The aim of this review was to study the relationship between circadian rhythms and physical performance, according to the latest published data.

In addition, the physiological processes involved in the physical response and the differences according to the type of sport and athletes' characteristics were studied. A bibliographic search was carried out through five databases, focusing on articles published in the last ten years and written in English and Spanish.

36 papers met the inclusion criteria. Body temperature is a factor that shows a circadian pattern with a marked peak in the later afternoon, time of the day at which physical performance is at its highest, i.e. speed, agility, distance covered, jumping power.

The perception of effort is also higher in the afternoon. Regarding the chronotype, evening types seem to be the most affected to do sports out of their optimal time-of-day. The tendency shows more morning types as age increases.

Training sessions should be planned according to the optimal time of day for each athlete. It's essential to take into account individual chronotype. The desynchronization of circadian rhythms can cause a decrease in physical performance."