The acute effect of intermittent palm and sole cooling on resistance training volume: a systematic review and meta-analysis

Intermittent palm (PC) and sole cooling (SC) are emerging techniques with potential ergogenic effects under high-intensity and fatiguing exercise conditions. However, evidence regarding their efficacy remains inconclusive. This systematic review and meta-analysis aims to summarize the acute effects of intermittent PC and SC applied during inter-set rest periods on resistance training volume and rate of perceived exertion (RPE) in healthy individuals. A systematic literature search in the electronic databases Cochrane, PubMed, Scopus, SPORTDiscus, and Web of Science identified 10 studies (n = 182 participants, 40 female, mean age range: 19 – 26 years). Effect sizes (Cohen’s dz) were calculated for each study and corrected for small sample bias (Hedges g). Meta-analyses were conducted using a random-effects model and an inverse variance method. PC and SC were applied for 1–3 min (2.3 ± 0.7 min) with temperatures ranging from 10–15 °C (12.0 ± 2.2 °C). Based on the current literature, no significant effect of PC or SC on resistance training volume was observed (n = 12, g = 0.22, 95%CI [-0.27, 0.72], p = 0.345), with high heterogeneity values indicating considerable variability among studies. Furthermore, no significant effect of PC or SC on RPE was found (n = 9, g = 0.10, 95%CI [-0.15, 0.32], p = 0.389). Based on current evidence, intermittent PC and SC cannot be generally recommended for resistance training volume enhancement.