Asymmetries of Maximum Hand Grip-, Trunk Rotation and Extensor Strength of the Lower Extremities in Healthy Active Males

Abstract

asymmetric movement patterns of arms, legs and trunk rotation (tr) often occur in everyday-life or sport and can provoke bilateral adaptations. Leg strength asymmetries (sa) or often-executed unilateral trs are associated with injuries of the lower extremities or back pain. aim was to determine maximum strength by considering handedness and footedness. higher maximum hand grip strength (hGs) was expected for the preferred hand in young active men, and bilateral sa for the support leg, but no sa of maximum tr. 30 participants (26.5 ± 3.5 years) realized maximum strength tests of isometric hGs, isokinetic concentric extensor strength during double-leg conditions in the leg-press (v=180 mm/s) and unilateral tr (ω = 120°/s). analysis of variance considered the test data and sI for left and right extremities. Maximum hGs showed significant asymmetries (5 or 6.9%) for the right hand (26 right-handed). right-handedness was combined with a significantly stronger left leg (3.7%) without sa of tr. sa is explained by the functional specialization (handedness, footedness). the small differences might be the result of the type of fitness training of the participants. to compensate sa it is necessary to combine unilateral training for increasing maximum strength potential of one side with bilateral strength exercises to improve neuromuscular control.