Repeat sprint fatigue and altered neuromuscular performance in recreationally trained basketball players [Article Review]
- Whistle Performance
- Feb 23
- 3 min read
Study Overview and Objectives
The primary aim of this study was to investigate how acute fatigue induced by a sport-specific repeat sprint ability (RSA) protocol affects neuromuscular performance in recreationally trained basketball players. Specifically, the researchers sought to measure changes in Countermovement Jump (CMJ) and Drop Jump (DJ) performance metrics immediately following fatigue and after a short recovery period.
A secondary objective was to determine if an athlete's fitness level—specifically their performance during the RSA protocol—influenced how their neuromuscular performance changed under fatigue.
Methodology
• Participants: The study included 25 recreationally trained basketball players (21 males, 4 females) with at least four years of organized playing experience.
• Protocol:
1. Pre-Test: Participants performed three CMJs and three DJs on force plates to establish baseline metrics.
2. Fatigue Protocol (RSA): Participants completed a Repeat Sprint Ability assessment consisting of 10 x 30-meter shuttle sprints (15m + 15m), separated by 30 seconds of passive recovery. This protocol was designed to induce fatigue comparable to competitive match-play.
3. Post-Tests: The jump tests (CMJ and DJ) were repeated at two specific time intervals following the sprints:
▪ Post-RSA1: 2 minutes after the protocol (simulating a timeout or quarter break).
▪ Post-RSA2: 15 minutes after the protocol (simulating a halftime break).
Key Findings: General Sample
When looking at the group as a whole, the study found that fatigue primarily affected outcome metrics (the result of the jump) rather than just the movement strategy.
• Jump Height: There was a significant decrease in CMJ jump height at both 2 minutes and 15 minutes post-fatigue compared to baseline. DJ jump height was significantly lower only at the 2-minute mark.
• Movement Strategy Changes:
◦ Shallower Depth: Participants utilized a significantly shallower countermovement depth during CMJs after fatigue.
◦ Faster Contraction: Contraction times significantly decreased (became faster) at both post-fatigue time points.
◦ Efficiency: Despite being fatigued, participants appeared to jump "more efficiently" in some aspects, showing greater eccentric peak power and deceleration force 15 minutes post-exercise.
The Role of Fitness (RSA Ability)
The researchers split the participants into "High" and "Low" performance groups based on their ability to maintain sprint speed during the fatigue protocol. This revealed that fitness levels significantly altered the fatigue response:
• Eccentric Velocity: The "High" RSA group (fitter athletes) actually increased their eccentric peak velocity immediately post-fatigue, whereas the "Low" RSA group experienced decreases.
• Peak Power: The "Low" RSA group saw significant decreases in peak power immediately after the sprints. In contrast, the "High" RSA group showed slight, non-significant increases, potentially due to a post-activation potentiation effect (a temporary boost in performance following heavy exercise) often seen in fitter athletes.
• Reactive Strength Index (RSI): In the DJ test, the "High" RSA group improved their RSI scores post-fatigue, while the "Low" RSA group's scores declined.
The "Learning Effect"
A critical finding was the presence of a learning effect, which may have masked some fatigue symptoms. Because the participants were recreationally trained and not professional athletes, they were less familiar with the specific jump testing protocols.
• The study found that the Coefficient of Variation (CV%)—a measure of consistency—decreased significantly for the Drop Jump over time.
• This suggests that participants were becoming more skilled at the test during the experiment. Consequently, improvements in metrics like contraction time might be attributed to learning the movement rather than a physiological recovery or strategy change.
Practical Applications and Conclusion
• Metric Selection: For populations with less testing experience (like recreational athletes), practitioners should focus on outcome metrics like Jump Height, as these reliably decrease with fatigue. Strategy metrics (how the jump is performed) may be unreliable due to learning effects.
• Monitoring Fatigue: Neuromuscular performance testing post-training or post-game can provide valid insights into athlete readiness. However, an athlete's specific fitness level must be accounted for, as fitter athletes may mask fatigue through more efficient movement strategies or potentiation effects.
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