DATASET FOR STUDY: Comparison of Short-term Effects of Eccentric Quasi-Isometric and Isokinetic Heavy-Slow Resistance Exercise on Pain, Range of Motion, and Strength Performance of Ankle Plantar Flexors

PURPOSE: Recently, there has been a growing interest in optimising exercise protocols in sports training and rehabilitation, with an increasing emphasis on eccentric quasi-isometric contraction, which involves maintaining joint/body position until isometric failure and resisting during the next eccentric phase. However, the research comparing EQI with other exercise modes is scarce. This study compared the short-term effects of ankle plantar flexors after executing either EQI or isokinetic heavy-slow resistance (IHSR) protocols on pain, range of motion (RoM), and strength performance. METHODS: A quasi-randomized study with 32 physically active participants divided into EQI (n = 16) and IHSR (n = 16) groups assessed outcomes at four-time points (pre-protocol, immediately post-protocol, 24- and 48-hour follow-ups), with each groups performing 3 sets of the exercise, interspersed with 3-min breaks. The primary outcomes were pain, ankle range of motion, strength performance and total impulse. RESULTS: The EQI group achieved significantly greater total impulse (p = 0.028), shorter time under tension (p = 0.001), and lower effort scores (p < 0.001). Group × time interaction revealed less decline in maximal voluntary isometric contraction torque (p = 0.002; η2 = 0.16), lower general pain (p < 0.001; η2 = 0.32) and activity-related pain (p < 0.001; η2 = 0.32) in the EQI group compared to IHSR, with no significant interaction for changes in ankle dorsal flexion RoM (p = 0.893). CONCLUSION: The EQI protocol was found to be more effective in accumulating high torque impulse while causing less fatigue and post-exercise pain than the IHSR protocol.