Effects of thermal agents on electrical sensory threshold and current tolerance when applied prior to neuromuscular electrical stimulation

Abstract

BACKGROUND AND OBJECTIVE: This study aimed to investigate the effects of thermal agents on electrical sensory threshold and current tolerance when applied prior to neuromuscular electrical stimulation. METHODS: In this single-blind and cross-over trial, electrical sensory threshold and current tolerance of 24 healthy volunteers were evaluated by using biphasic symmetrical pulses (240 mu sec, 50 pps), before and after thermal agent (cold pack, hot pack and ultrasound) applications. RESULTS: Electrical sensory threshold increased after cold-pack, and current tolerance reduced after hot-pack applications (p < 0.05). Inter-agent comparisons of pre and post-application differences of the investigated parameters revealed that the most obvious effects were caused by application of hot pack. CONCLUSIONS: Hot pack application prior to neuromuscular electrical stimulation (NMES) may reduce current tolerance and limit to reach the desired current intensity for strengthening the electrically induced contractions. Results are considered to be valuable for physiotherapists, who apply thermal agents and NMES consecutively, in their treatment programs.