Symmetric and Asymmetric Two-Handed Pull-Push Strength of Young Adults

Abstract

Forty normal young adults volunteered for an experiment in which they were required to perform two-handed maximal pull-push in isometric and isokinetic modes (50 cm/s linear velocity of the handle) at 50-, 100-, and 150-cm heights of handle in sagittal, 30-deg lateral, and 60-deg lateral planes. Subjects were stabilized on a circular platform that rotated on its axis and allowed fixation in any position to achieve asymmetric settings. The pull-push strengths were applied to a 53-cm wide handle and were measured through the load cell assembly of the Static Dynamic Strength Tester. The peak and average strengths were compared statistically, and an ANOVA and multiple regression were performed. The main effects of gender, activity (pull or push), mode (isometric or isokinetic), plane (sagittal, 30 deg lateral, or 60 deg lateral), and height (low, medium, or high) of activity for both peak and average strengths were highly significant (p < 0.01). All subjects were strongest in pulling activity in the isometric mode in the sagittal plane at medium height. Males were significantly stronger than females for most activities. However, with increased postural asymmetry, the difference between genders declined.

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