Palm Cooling: Something to Grasp, or All Hype?

Early studies on palm cooling during resistance training reported some pretty impressive results. While there are possible reasons why it could work, recent research hasn't been so encouraging. In this study, the researchers looked at whether cooling your palms between sets could improve performance during a full-body workout. Is it all hype, or worth considering? Read on to find out.

Overview

• What did they test? Twenty-five trained individuals (12 females and 13 males) completed two resistance training sessions, one with palm cooling between sets and one without. All sets were performed to failure, with a range of performance, perceptual, and physiological measures assessed during both sessions.
• What did they find? There were no practically meaningful differences between conditions. A small difference favoring palm cooling was observed in post-session jump performance, but the authors cautioned against interpreting this as a meaningful benefit.
• What does it mean for you? These findings, alongside other recent research, suggest that palm cooling between sets is unlikely to meaningfully improve resistance training performance, making it difficult to justify the effort required to implement this practice.

What’s the Problem?

I first heard about the idea of palm cooling to improve exercise performance when a friend suggested I listen to an early episode of the Huberman Lab podcast. My first thought was that it sounded too good to be true. I’m naturally skeptical of training aids or supplements that make extraordinary claims. Why? Because I know people are always looking for a hack, something that can immediately improve their performance. The problem is that these shortcuts are few and far between, and even if they work, their effects tend to be far less impressive than the claims typically suggest.

So why the hype around palm cooling? Well, an early study by Grahn et al. 1 in 2012 reported some impressive results and was discussed in the podcast episode I was told to listen to. In separate experiments, three weeks of bench press training with palm cooling increased training volume by 40%, compared with 13% without cooling. Meanwhile, pull-up volume increased by 144% over six weeks of training with palm cooling in experienced participants, compared with just 5% during a shorter two-week period without cooling. Furthermore, bench press 1RM increased by 22% over a ten-week training program, which included four weeks without cooling followed by six weeks with cooling.

How might palm cooling have produced these results? The palms and soles of the feet contain specialized blood vessels that allow for efficient heat transfer between the body and its surroundings. The researchers suggested that cooling blood through the palms could reduce heat buildup in working muscles, potentially limiting the effects of higher temperatures on energy production and so delaying fatigue.

At first glance, these results might make you want to run out and buy some cooling mitts. Before you sprint out the door, there are some important limitations. First, the pull-up findings compared training periods of different durations. Second, while bench press strength increased by 22% over ten weeks, strength wasn't retested after the initial four weeks without cooling, making it impossible to isolate the effect of palm cooling. Finally, the sample sizes were small. While impressive, these early findings needed confirmation through more rigorous research.

Since then, several studies have investigated the effects of palm cooling on resistance exercise performance. In this review, we'll examine one of the latest studies to see how its findings stack up against those early claims.

Purpose

This study aimed to examine the effects of palm cooling between sets during a full-body resistance training session on exercise performance and a range of perceptual and physiological measures.

Hypothesis