In recent years there’s been an increasing recognition of the importance of the daily biological rhythm (circadian rhythm) in physical performance. Previous studies on athletes have suggested that certain aspects of physical performance such as power and strength tend to peak during late afternoon/early evening. But now a new study by UK scientists suggests that an individual’s internal body clock has an even more powerful influence on performance than was previously suspected.
The researchers asked 20 female hockey players to perform a test consisting of a series of 20m runs at a progressively faster pace until they could no longer continue. The tests were then repeated at six different times of the day (7am, 10am, 1pm, 4pm, 7pm and 10pm) and performances compared.
Averaged over the whole group, peak performance tended to occur during the late afternoon. However, when the researchers split the group into those who were natural early risers (larks), late risers (owls) or intermediates, they discovered that the larks tended to peak around midday, the intermediate risers around 4pm, and owls shortly before 8pm. Astonishingly, the performance of some individuals varied by as much as 26 per cent according to the time of day of their test, e.g. the ‘owls’ performed better during the evening.
Although this study looked at hockey players, there’s every reason to believe these same patterns would be observed in cyclists too — the implication being that timing your hardest training sessions and racing according to whether you’re a lark, owl or intermediate could reap big performance rewards.
Words by Andrew Hamilton.
This article first appeared in the February 19 edition of Cycling Weekly