Cryotherapy and Cold Water Immersion
Whole body cryotherapy and cold water immersion benefits are likely non-existent or modest at best, and are very prone to placebo. One potential application for cryotherapy would be following training during a multi-event competition scenario, over a short (~3 day) span, for what is likely a perceived reduction of DOMS and recovery or potentially attenuation of inflammation. It is prudent to avoid regular cryotherapy and cold water immersion treatments as they may attenuate some benefits of exercise. Alternatively, cool water therapy could be of value in preventing or treating hyperthermia.
According to Wilson et al. (2018) neither cryotherapy intervention (whole body cryotherapy or cold water immersion) was more effective than the placebo treatment at accelerating recovery. The implications of these findings should be carefully considered by individuals employing cryotherapy as a recovery strategy following heavy load resistance training.
A Systemic Review and Meta-Analysis (in which a total of 36 articles were processed, with pooled data from 27) by Hohenauer et al. found: “There was no evidence that cooling affects any objective recovery variable in a significant way during a 96 hrs recovery period.”
Furthermore, as discussed in the following studies, cryotherapy/cold water immersion is potentially detrimental long-term. It appears to attenuate both muscular and vascular adaptations to training. The reason a few acute studies suggest positive benefits beyond placebo appears to be due to hormesis (Roberts et al provide insight into this over multiple studies).
Yamane et al. (2015) found that chronic post-exercise cold application actually blunted muscle adaptation over a 6 week period. Thicknesses of the experimental arms increased after training in both groups, but the extent of each increase was significantly less in the cooled group compared with the non-cooled group. Maximal muscle strength and brachial-artery diameter did not increase in the cooled group, while they increased in the non-cooled group (this suggests that results were not confounded by post-exercise swelling). Local muscle endurance increased in both groups, but the increase in the cooled group tended to be lower compared to the non-cooled group. This study showed that regular post-exercise cold application to muscles potentially attenuates muscular and vascular adaptations to resistance training.
Roberts et al. (2015) investigated functional, morphological and molecular adaptations to strength training exercise and cold water immersion (CWI) through two separate studies over a 12 week period. They concluded: “Cold water immersion attenuates the acute changes in satellite cell numbers and activity of kinases that regulate muscle hypertrophy, which may translate to smaller long-term training gains in muscle strength and hypertrophy. The use of cold water immersion as a regular post-exercise recovery strategy should be reconsidered.”
Schalt et al. (2018) found: “Despite a pronounced caloric deficit and sustained activity under extreme cold conditions, fat free mass was preserved with an increase in serum follistatin and acetoacetate.” What this essentially suggests is that subjecting yourself to cold for the purpose of fat loss is actually counterbalanced by your system up-regulating substances such as follistatin and acetoacetate
Figueiredo et al. (2016) concluded: “coordinated upstream signaling and activation of transcriptional factors stimulated pre-rRNA expression after resistance exercise. Cold water immersion (CWI), as a recovery strategy, markedly blunted these events, suggesting that suppressed ribosome biogenesis may be one factor contributing to the impaired hypertrophic response observed when CWI is used regularly after exercise.”