Ice baths aren’t just for fundraisers and annual polar bear plunges. Athletes and coaches use frigid post-exercise dips to help reduce muscle soreness and speed up recovery – or that’s the theory. If you’re looking to build muscle, you may want to skip the cold water therapy, according to research. Dr. Llion Roberts and colleagues, from Queensland University, Australia, have found that ice baths can actually blunt the process involved in muscle growth.
The researchers included 21 physically active men in this study. The men were instructed to exercise with strength training two days a week for 12 weeks. Roughly half of the group completed their exercises with a cool down routine on an exercise bike, while the other group dipped into ice baths (10 degrees Celsius). The research has been published in The Journal of Physiology.
The 12 week trial found that muscle mass and strength increased more in the group that used the exercise bike to cool down. This confirmed previous data from another study in which muscle biopsies were taken from a group of men who performed single-leg workouts. The biopsies were taken either after an ice bath or an active cool down. This prior study showed that pathways and satellite cells (sometimes referred as muscle stem cells) involved in the muscle building process were “blunted” for up to two days post exercise in the ice bath group.
“We found that cold water immersion after training substantially attenuated, or reduced, long-term gains in muscle mass and strength,” Dr. Roberts said. “It is anticipated that athletes who use ice baths after workouts would see less long-term muscle gains than those who choose an active warm down.
The researchers are unsure why ice baths have this effect on the growth process of muscles. One theory, is that cold water constricts blood flow, which causes less blood and nutrients to enter the muscles. Dr. Jonathan Peake, from Queensland University of Technology, suggests that athletes stay clear of ice baths – especially after strength training.
“This is the most comprehensive study of its kind and the results suggest individuals who use strength training to improve athletic performance, recover from injury or maintain their health, should reconsider using cold water immersion as a recovery aid,” he said.
- Llion A Roberts, Truls Raastad, James F Markworth, Vandre C Figueiredo, Ingrid M. Egner, Anthony Shield, David Cameron-Smith, Jeff S. Coombes, Jonathan M Peake. Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. The Journal of Physiology, 2015; DOI:10.1113/JP270570