Bench Press & Pull-up Study from Stanford University
In the study “ Work volume and strength training responses to resistive exercise improve with periodic heat extraction from the palm , ” Stanford University biologists Dennis A. Grahn et al., investigated
- whether there is a correlation between increased body temperature and the onset of [muscle] fatigue during resistance training, and
- whether cooling the palm between repetition sets during resistance training affects strength endurance and training volume.
Body temperature was manipulated by 30-45 minutes of exertional treadmill exercise in the heat with or without palm cooling. Training volume was then assessed by 4 sets of bench presses with a fixed load. Body temperature could be reduced and training volume increased by palm cooling.
Control group: Tes (body temperature) = 39.0 ± 0.1°C, 36 ± 7 repetitions
Cooling group: Tes = 38.4 ± 0.2°C, 42 ± 7 repetitions, mean ± standard deviation, n = 8, p < 0.001).
In separate experiments, the influence of palm cooling on exercise volume and resistance training responses was evaluated. Participants performed two sessions per week of bench press or pull-ups for several consecutive weeks. Palm cooling was applied for 3 minutes between sets.
Over 3 weeks of bench press training, palm cooling increased training volume by 40% (vs. 13% in the control group without cooling; n = 8, p < 0.05).
Over 6 weeks of pull-up training, palm cooling increased training volume in experienced pull-up athletes by 144% (vs. 5% over 2 weeks in the control group without cooling; n = 7, p < 0.001) and in inexperienced pull-up athletes by 80% (vs. 20% in the control group without cooling; n = 11, p < 0.01).
Strength (maximum repetitions) increased by 22% over 10 weeks of pyramid bench press training (4 weeks without palm cooling followed by 6 weeks with palm cooling; n = 10, p < 0.001).
These results confirm previous observations on the effects of palm cooling on training volume, demonstrate a relationship between body temperature and the onset of fatigue during resistance training, and suggest a new approach to improving the resistance training and training volume response.
