Fatigue Impairs Jump Performance in Elite and Recreational Athletes
Injury rates are higher during games than they are in practice, despite the fact that most athletes spend more time practicing than competing. Besides just pushing harder during a game, technical, high-intensity moves like jump landings occur more often in a fatigued state when competing. Being tired while trying to execute these moves increases the chance of things going wrong. Researchers looked into the effects of fatigue in a recent study in the Journal of Strength and Conditioning Research.
In the study, the researchers tested both elite and recreational athletes to see how fatigue affected each group. The landing mechanics of each participant were measured ahead of time, and then again at one, five, ten, fifteen, and twenty minutes after a thirty-minute run. Landing mechanics were chosen because they occur frequently in athletics and can often result in injury.
To make sure it was fatiguing, the run was performed at each athlete’s anaerobic threshold. The anaerobic threshold is the point at which the metabolic waste products of anaerobic metabolism accumulate more rapidly than they can be disposed of. It is the point beyond which your body will give out before your mind does. After being fatigued, the mechanics of the landing were compared to the initial test and good landing form. The number and degree of the kind of errors that cause injury were measured for all participants.
The expected results of the study were confirmed. Fatigue did indeed reduce dynamic postural control. This means that in changing conditions – especially game time – the body was less able to adjust. However, in dynamic conditions those adjustments have to come from somewhere, and all too often they come at the expense of our joints and soft tissues.
What might come as a surprise, however, is that the advanced athletes lost control at the same rate as the recreational athletes. Although the advanced athletes seemed to recover a bit faster from fatigue, and the recreational athletes had a few more errors resulting from fatigue, both groups lost dynamic control after the exercise at anaerobic threshold. Think about what that means during actual performance. Coaches may believe their advanced athletes are safer, but this might not be so.
While this study looks specifically at jump landings, it’s even more important to extrapolate this to training in other movements. Skill movements, especially those involving ballistic actions should be avoided during fatigue whenever possible, especially during practice when the conditions are easier to control. Further, consistently practicing skills in a fatigued state is a great way to reinforce poor skills, which is something every coach should avoid.
In addition to avoiding skill work when fatigued, maneuvers with a high potential for injury should be emphasized in practice during highly controlled sessions. Based on this study it seems that practicing these skills during ideal conditions helps to reduce injuries. As a result, the researchers recommended that coaches work on these movements when they are fresh to reduce injury rates.
1. Benita Kuni, et. al., “Impaired jump landing after exercise in recreational and in high-performance athletes,” Journal of Strength and Conditioning Research, DOI: 10.1519/JSC.0000000000000431
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