The Study
Effects of high-intensity sprint exercise on neuromuscular function in sprinters: the countermovement jump as a fatigue assessment tool
This study watched 10 sprinters do a 400m run and then tested their jumping ability at different times after. It shows how their jump performance changed, but because everyone did the same thing and there was no 'normal' group to compare to, we can't say for sure the run caused the changes—we just see a pattern.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
After running a very fast 400-meter sprint, college sprinters’ jumping power stayed low for at least a full day, even though they said they felt fine.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 531 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes, this matters—athletes may still be physically tired even if they feel recovered, increasing injury risk if they train too soon.
- 2Jumping power was down 7.4%, pushing power during the jump was down 9.7%, and the jump movement changed to spend less time pushing up compared to slowing down—by 14.0% more time in the slow-down phase.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
PeerJ
Year
2024
Authors
Takahiro Hasegawa, Kotaro Muratomi, Yuki Furuhashi, Jun Mizushima, H. Maemura
Related Content
Claims (4)
After college guys run a really hard 400-meter sprint, their explosive jumping power stays about 10% lower the next day, showing their muscles are still tired even a full day later.
Even when male college sprinters say they feel back to normal after a hard 400-meter race, their leg power is still down by over 7% the next day — meaning their muscles might not be fully recovered even if they feel fine.
After running a 400-meter sprint really fast, college sprinters aren't as powerful when jumping — especially in the first part of the jump — and this weakness can last up to a full day.
After a really hard sprint, college male runners seem to jump differently for over a day — their muscles spend more time stretching and less time shortening, which might be their body’s way of adjusting after intense effort.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.