High-intensity exercise usually causes muscle damage, or EIMD (Exercise-Induced Muscle Damage). It is accompanied by strength loss, soreness, oxidative stress and inflammation, factors that cause fatigue and a decrease of performance.
Sports recovery and cryotherapy
It is well known the importance of the recovery periods to get back to normal conditions and maximal performance as soon as possible. Thus, there are different approaches to accelerate recovery following exercise.
Among these recovery techniques is cryotherapy, based on reducing the temperature of the damaged tissue and/or body. Different approaches of this principle are used in techniques such as cold-water immersion or whole-body cryotherapy.
Cryotherapy using Phase Change Materials (PCM)
A recent review has focused on cryotherapy using Phase Change Materials, or PCM.
What are they and how do they work? PCM are packs filled with a blend of oils (palm, coconut, soybean or rapeseed) mixed with sodium chloride and encapsulated in plastic. They are solid and look like wax in frozen state and oil once they are melted in liquid state. Additionally, they stay at a temperature around 15°C for long periods of time (up to 3 hours).
What is the advantage of PCM against other cryotherapy techniques? The main benefit of PCM is that they allow to deliver a single dose of cooling for a prolonged duration. Meanwhile the duration of usual cryotherapy treatments is usually too short to reduce muscle temperature. Longer cooling reduce strength loss and soreness after exercise, enhancing recovering.
Moreover, PCM are simpler and more practical to apply than other cryotherapy techniques, as athletes may continue with their daily activities, with no reported adverse effects.
Several studies have shown that prolonged cooling using PCM at 15°C was successful in accelerating recovery following eccentric exercise, soccer and baseball, but showed no improvement in marathon running. A possible explanation is that cooling (PCM packs on the quadriceps) was applied one hour after finishing the marathon. In runners averaging 4h of finishing times it would mean that cooling started 5h after initiating the exercise.
But not everything is about sports performance. Ice application is the standard treatment in strain injuries and contusions. PCM could be a complementary cryotherapy treatment after a traditional 20-30 minutes ice treatment. First, we would cool rapidly the damaged tissue with ice before focusing on keeping its temperature low for a long period using the PCM.
Nevertheless, there is growing evidence against the use of cooling therapies for injuries, as they could delay the natural healing regeneration process. Furthermore, some authors even suggest that all the effects of cooling techniques are due to a placebo effect.
- PCM cooling techniques could complement traditional cryotherapies by prolonging cooling time.
- PCM cooling is safe, inexpensive and allow athletes to continue with their daily routines.
- PCM has been primarily used to reduce EIMD and accelerate recovery, but also has potential in treating soft tissue injuries and the inflammatory response in chronic diseases such as rheumatism.
Do you use any cryotheraphy/cooling technique to help with your recovery?
Do you think that they are useful?
Prolonged cooling with phase change material enhances recovery and does not affect the subsequent repeated bout effect following exercise. Kwiecien, S. Y., O’Hara, D. J., McHugh, M. P., and Howatson, G. (2020). Eur. J. Appl. Physiol. 120, 413–423. doi: 10.1007/s00421-019-04285-5.
Don’t Lose Your Cool With Cryotherapy: The Application of Phase Change Material for Prolonged Cooling in Athletic Recovery and Beyond. Kwiecien, S.Y., McHugh, M., & Howatson, G. (2020). Frontiers in Sports and Active Living. Front. Sports Act. Living, 15 October 2020. doi: 10.3389/fspor.2020.00118.