Electromyographic study of the peroneus longus muscle during bridging activities.

The purpose of this study was to investigate the electrical activity of the peroneus longus muscle in 12 normal subjects during eight variations of bridging. Electromyographic recordings were made using fine-wire electrodes and an ink-writing polygraph. Differences in the amount of electrical activity during bilateral and unilateral bridging, with and without heels elevated 1.5 inches, and with and without the applications of maximal manual resistance to the lateral surface of the knee were investigated. Statistical analysis revealed that overall posture, heel elevation, and resistance produced significant effects in the electrical activity of the peroneus longus muscle. Resistance applied during bridging increased activity only when the heels were not elevated. Unilateral bridging produced a greater amount of electrical activity than bilateral bridging; elevated heels produced greater activity than unelevated heels; applying resistance produced greater activity than not applying it. Suggestions for further study were made.