Influence of Experience and Attentional Focus in a Single Arm Isokinetic Elbow Flexion

Abstract

Previous research has shown that adopting an external focus (i.e., movement of the handle), rather than an internal focus (i.e., muscle contraction) increases force output and decreases muscle activation during an elbow flexion movement in men and women with strength training experience. However, little is known about the influence of attentional focus in novice populations. PURPOSE: To determine the influence of attentional focuses on muscle activation and force output among experienced and inexperienced males performing a unilateral isokinetic elbow flexion. METHODS: Fourteen male participants with >3 years of strength-training experience (EX group mean age 20.6 ± 0.9) and 9 novice participants with <6 months of resistance training experience (NOV group mean age 19.5 ± 1.0) performed 10 repetitions of a unilateral elbow flexion using a Biodex System 4 dynamometer. Repetitions were performed under 3 conditions (a control followed by randomly assigned internal and external focuses) at a speed of 60°(s-1). Peak torque (N·m) was measured by the Biodex, and peak muscle activation (mV) of the biceps brachii was measured using surface EMG. RESULTS: Within-group differences were analyzed using a repeated measures MANOVA. In the EX group, an external focus showed significantly higher peak torque (65.3 ± 3.2 N·m) than both the control (60.0 ± 3.2 N·m) and internal (50.1 ± 4.2 N·m) focus (all p<0.05). For the NOV group, there were no significant differences in peak torque production between any conditions. Further, there were no within-group significant differences in peak muscle activation for either group. CONCLUSION: Supporting previous research, our results show that adopting an external focus yields greater force output than an internal focus for experienced populations. However, no difference in force output is observed in novices with an external or internal focus. Thus, instructing experienced individuals to adopt an external focus may be beneficial for exercises where maximum force output is the goal, but additional research is needed to better understand the influence of attentional focus for similar exercises among novices. Supported by University of St. Thomas Collaborative Inquiry Grant.