Post exercise recovery acceleration

Athletes place immense stress on their body on a daily basis. Recovery plans and diet regulation are extremely important to help these individuals recover to reach their peak performance. Cryotherapy and protein-rich diets are widely considered the best modes of recovery for athletes. However, recent studies have shown that cryotherapy may actually exacerbate the body’s healing process while heat is believed to improve post-exercise recovery. (1)  They also indicate protein-rich diets are less effective diet plans for recovery than carbohydrate-rich diets. (1)

Cryotherapy is a procedure in which an individual is exposed to cold temperatures to promote muscle recovery. (2) The mechanism of cold therapy for recovery after exercise is predominantly attributed to its vasoconstrictive effect, which reduces inflammation reactions through a decrease of the cell metabolism. (2) The physiological and biological effects are attributed to the reduction in temperature in various tissues, together with the neuromuscular action and relaxation of the muscles produced by the application of cold. (6) Cold increases the pain threshold, viscosity and the plastic deformation of the tissues and lowers the inflammatory response after exercise. (6) 

However, a study published by the Journal of Physiology claims that using heat on muscles accelerates the rate of recovery while cooling them actually slows the rate of recovery. (1) The study investigated whether intramuscular temperature affects the acute recovery of exercise performance following fatigue induced by endurance exercise. It was found that the recovery of submaximal force capability and restoration of fatigue resistance was worsened by cooling (16–26°C) and improved by heating (36°C). (1). The findings indicate that cryotherapy may actually slow muscle recovery by slowing glycogen resynthesis and impairing fatigue resistance during subsequent exercise. Instead, heating the muscle increases recovery rate by increasing the rate of biochemical reactions that promote healing. (2) Heat attenuates cellular damage and protein degradation. (7)  Heat also increases the expression of heat shock proteins (HSPs) and upregulates the expression of genes involved in muscle growth and differentiation. (8) These findings are consistent with the fact that the rate of biological or chemical system metabolic reactions generally becomes slower when the temperature is lowered. (1)

Diets rich in protein are usually considered best to help muscle recovery, but emphasizing carbohydrates rather than protein has been shown to increase the rate of muscle recovery. (1)  In healthy, recreationally active individuals, skeletal muscle proteins display a turnover rate of ~1.2% a day. (4) After exercise, the muscles in the body are subjected to microtears. Protein consumption after exercise has been a popular mode of recovery for many athletes and healthy individuals. It is believed to help repair muscle, reduce pain, and restore performance. (4) Consuming proteins after exercise recovers peripheral blood mononuclear cell proliferation. (5) The branched-chain amino acids (BCAA) in protein, particularly leucine, have an anabolic effect on protein metabolism by increasing the rate of protein synthesis and decreasing the rate of protein degradation, (3) further contributing to muscle recovery. 

However, a recent study has shown that protein consumption post exercise may not be the most effective diet for muscle recovery rate. (1) Instead, the consumption of carbohydrates speeds up muscle recovery rate by improving maximum force during exercise, glycogen resynthesis, calcium concentration, and fatigue resistance. (1) The results of acute exercise studies show that those who consumed carbohydrates during the post-exercise recovery period had a quicker recovery of the force and endurance capacities of exercised muscle compared to those who consumed more protein. (1) Based upon the fact that fatigue during intense prolonged exercise is commonly due to depletion of muscle and liver glycogen which limits both training and competitive performance, it is advised to have a high carbohydrate intake at all times before, during and after exercise. (8)

Cryotherapy, a popular post exercise recovery method may not be as effective as has been believed. In fact, it may exacerbate rather than improve muscle recovery rate. Similarly, high-protein diet plans may not be as effective for recovery as a carbohydrate-rich diet. These new discoveries may change the way athletes design their recovery plans and achieve their maximum performance capabilities.

Works cited

1. Cheng, A. J., Willis, S. J., Zinner, C., Chaillou, T., Ivarsson, N., Ørtenblad, N., … & Westerblad, H. (2017). Post‐exercise recovery of contractile function and endurance in humans and mice is accelerated by heating and slowed by cooling skeletal muscle. The Journal of Physiology, 595(24), 7413-7426. 
2. Hohenauer, E., Taeymans, J., Baeyens, J. P., Clarys, P., & Clijsen, R. (2015). The effect of post-exercise cryotherapy on recovery characteristics: a systematic review and meta-analysis. PLoS one, 10(9), e0139028.
3. Blomstrand, E., & Saltin, B. (2001). BCAA intake affects protein metabolism in muscle after but not during exercise in humans. American Journal of Physiology-Endocrinology And Metabolism, 281(2), E365-E374.
4. Tang, J. E., & Phillips, S. M. (2009). Maximizing muscle protein anabolism: the role of protein quality. Current Opinion in Clinical Nutrition & Metabolic Care, 12(1), 66-71.
5. Negro, M., Giardina, S., Marzani, B., & Marzatico, F. (2008). Branched-chain amino acid supplementation does not enhance athletic performance but affects muscle recovery and the immune system. Journal of Sports Medicine and Physical Fitness, 48(3), 347.
6. Swenson, C., Swärd, L., & Karlsson, J. (1996). Cryotherapy in sports medicine. Scandinavian journal of medicine & science in sports, 6(4), 193-200.
7. McGorm, H., Roberts, L. A., Coombes, J. S., & Peake, J. M. (2018). Turning up the heat: an evaluation of the evidence for heating to promote exercise recovery, muscle rehabilitation and adaptation. Sports medicine, 48(6), 1311-1328.
8. McGorm, H., Roberts, L. A., Coombes, J. S., & Peake, J. M. (2018). Turning up the heat: an evaluation of the evidence for heating to promote exercise recovery, muscle rehabilitation and adaptation. Sports medicine, 48(6), 1311-1328.