Daily variation in performance measures related to anaerobic power and capacity: A systematic review.
Level 1 - systematic review of randomized trials
Systematic review of experimental crossover/repeated-measures studies
PubMed 34978950 · doi:10.1080/07420528.2021.1994585
What was done
Authors searched PubMed, Scopus, SPORTDiscus, and Web of Science through May 2021 for experimental studies in adult males (aged ≥ 18 years) assessing anaerobic power or capacity between at least two time points in a day (morning vs. evening). A total of 55 studies were included (39 assessing anaerobic power, 25 assessing anaerobic capacity).
What was found
Forty-eight of 55 studies reported significantly higher performance variables in the evening than the morning, whereas 7 studies found no significant time-of-day differences. Diurnal differences favoring the evening varied by test modality: jump tests (2.7% to 12.3%), force-velocity tests (~8%), sprint tests (2.7% to 11.3%), 5-m multiple shuttle run tests (3.7% to 13.1%), Wingate tests (1.8% to 11.7%), and repeated sprint tests (3.4% to 10.2%). The running-based anaerobic sprint test (RAST) was the only test showing no diurnal variation.
Why it matters
Anaerobic power and capacity systematically peak in the evening in adult males across varied testing modalities. This demonstrates that testing schedules and athletic performance evaluations must rigorously control for time of day.
Limits
The review was restricted to adult males, precluding generalization to females or adolescents. The primary studies lacked standardized protocols and largely failed to control for chronotype, sleep, motivation, or habitual training times; no quantitative meta-analysis was performed.
Cited by
- supports In the late afternoon, resting heart rate is relatively higher, core body temperature is warmer, and muscle tone and joint flexibility are improved compared to the early morning.