Influence of Sport Activity on Trunk Muscle Performances

Introduction:
Lumbar pain among athletes is a common problem and can be challenging for athletic trainers and therapists. Unfortunately, little is known about the capabilities of trunk muscle function in elite athletes Therefore, an objective assessment of muscle performance is relevant in injury prevention and rehabilitation.
The purpose of this study was to examine the specific trunk muscle strength and endurance in different sports i.e. swimming, rowing and tennis.

Methods:
We assessed maximum isometric trunk extensor, rotator, flexor and lateroflexor muscle strength as well as trunk extensor muscle endurance of 10 swimmers, 10 rowers, 10 tennismen and 10 sedentary students (control group). Strength was measured by means of specific trunk dynamometers.
An adaptation of the Sorensen test was performed to assess trunk extensor endurance.

Results:
Muscle strength appeared generally higher among athletes than among control subjects. However, differences were statistically significant only with swimmers for trunk flexors (p<0.05) and trunk rotators (p<0.05), with rowers for trunk flexors (p<0.05) and with tennismen for dominant lateroflexors (p<0.05) and non-dominant trunk rotators (p<0.05). No significant bilateral difference appeared for trunk lateralflexors strength. For trunk rotators, tennismen were significantly stronger in the non-dominant side (p<0.05). Trunk extensor endurance was higher among rowers than among the other groups.

Conclusion:
This study underlined several differences in trunk muscle performance between athletes and control subjects as well as within athletes groups in relation to their sports. Further studies would clarify the full significance of these results with respect to performance and injury.