Cool in theory, not in practice: Effects of interset palm cooling on resistance exercise performance and psychophysiology responses

Previous research has explored distal extremity cooling as a strategy to enhance exercise performance. However, it remains unclear whether the intervention may aid in physiological or performance-oriented outcomes in an ecologically valid context. This study’s primary purpose was to evaluate the effects of interset palm cooling (IPC) using a water cooling device during a full-body (FB), multi-set resistance training (RT) protocol on performance and perceptual measures. In a randomized crossover design, participants completed a familiarization session with 10RM testing and two randomized experimental sessions. Experimental sessions consisted of an FB RT protocol with either IPC (10–15°C) or control (CON) (22–28°C) applied for 2 min. between sets. Assessments included exercise performance (repetitions to failure, volume load, fatigue index, pre-post countermovement jump), subjective psychological markers (discomfort, session rating of perceived exertion), and physiological measures (heart rate, blood lactate, and tympanic temperature). Twelve trained females and 13 trained males completed the study. Bayesian analysis revealed low likelihood of any difference on any measured variables between conditions. The current study suggests that IPC is unlikely to enhance objective performance or improve subjective experience in hypertrophy-oriented RT.