Palm Cooling Delays Fatigue and Improves Performance
A new study was performed to determine if body core cooling via the palm of a hand could increase work volume during exercise. The study investigated whether there was a correlation between elevated core temperatures and fatigue onset during exercise, and whether or not palm cooling between sets of resistance exercise affected strength and work volume training responses.
There were a total of 67 subjects who participated in the study, ranging from 19 to 23 years old. There were three protocols used in this study: heat stress and fatigue, work volume training response, and strength training response. In the heat stress and fatigue protocol, the core temperature of each participant was manipulated with 30-45 minutes of fixed load and treadmill exercise in the heat with or without palm cooling. Work volume was then assessed by four sets of a fixed load bench press.1
Details of the study protocols were as follows:2
- The work volume training response protocol consisted of repeated sets of overhand grip pull-ups or bench press exercises that were separated by three minute rest periods. The subjects performed two trials per week, and either underwent palm cooling during the rest period or did not partake in palm cooling during the rest period. Each set of the exercises was performed to failure.
- There were two pull-up studies: in one pull-up study, there were 7 subjects who participated in a 6-week series of palm cooling during rest periods, and either a 2 week series of rest-only trials or a 6 week series of rest only trials. The routine consisted of 10 sets of pull-ups. In the second pull-up study, 11 athletes who were new to pull-up exercises participated in 12 sequential trails with palm cooling during rest periods, and 12 sequential trials with no palm cooling. The exercise routine consisted of 6 sets of pull-ups.
- There was also a bench press group which included 17 subjects who participated in 5 bench press workouts. The weights were 50% of 1RM, and remained constant throughout the study. Each workout consisted of 6 sets of bench press.
- The strength training response protocol included 10 subjects participated in a bi-weekly 10-week training program. The program consisted of 6 sets of bench press with 3 minute rest periods. The workouts were of a pyramid design. The experimental manipulations were either rest only, or palm cooling during rest periods. The treatment order was interset rest only for the first eight training sessions (4 weeks) followed by palm cooling during interset rest for the subsequent 12 sessions (6 weeks).
The study determined the palm cooling resulted in a 40% increase in work volume, compared to only a 13% in participants with no cooling treatment. Over 6 weeks of pull-up training, palm cooling increased work load volume by 144%, compared to 5% of those who performed pull-ups with no palm cooling, and 80% in the new pull-up subjects. The strength of those who performed pyramid bench press training for 4 weeks with no treatment followed by 6 weeks with palm cooling, increased by 22%.3
The results of this study verify that there is a correlation between core temperature and fatigue onset during resistance exercise, and may suggest a new method for training. There are a few devices currently on the market designed to cool palms and these have been targeted toward athletes whose sport is grip-intensive. Now, it seems, palm cooling may be useful to many athlete beyond its benefits to grip.
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