Reliability assessment of torque measures during a unilateral pressing movement.

Abstract

The context for this project was that a perceived overemphasis on conventional flat bench press training could be interfering with the ‘natural’ shoulder girdle functional movement patterns and, consequently influencing performance and injury susceptibility. The width of the conventional flat bench press exercise can obstruct and restrict the scapulae movements, potentially leading to compromised shoulder girdle function. This project sought to establish the reliability of assessing pressing strength with a novel isokinetic strength task with two seat-back conditions. OBJECTIVES: 1) To assess the reliability of torque measurements obtained during a novel unilateral chest press movement; and 2) observe the effect of a narrow (uninhibited scapula) seat-back on torque-angle profiles. METHODS: Twenty participants performed maximal effort (3 sets of 5 reps) unilateral pressing movement repetitions using an Isokinetic Dynamometer with a modified Lever arm attachment. Both arms were tested under two movement conditions (a narrow bench back, MOD; and a standard width bench back, STD) across three testing sessions. Reliability was determined using intraclass correlation coefficients (ICCs). RESULTS: Measures of peak torque and total work were measured reliably (ICCs all >0.68) both eccentrically and concentrically with two testing sessions using a novel unilateral pressing motion. There was no difference evident between movement conditions for any test measure (all p>0.078). CONCLUSIONS: Strength (torque) can be reliably measured in a full range pressing motion. This reliability permits future studies to explore the effect of different training intervention on eccentric and concentric shoulder strength. The results also indicate that participants can safely test through a full pressing range, which may benefit activities that involve full horizontal abduction under load.