Arsene Wenger has been quoted this week (Monday 25th September 2017) questioning the efficacy of cryotherapy amongst other interventions as ‘Smoke and mirrors’. (https://www.theguardian.com/football/2017/sep/24/arsene-wenger-pours-cold-water-cryotherapy-arsenal-games). The type of cryotherapy that Mr. Wenger is referring to is the type used by athletes to aid recovery (there are other medical applications for cryotherapy such as wart removal).
This type of cryotherapy does appear to be de rigueur for professional athletes and even hard core amateur athletes that are under taking significant challenges particularly endurance challenges. However, does the treatment work? And what does it do to make it ‘work’?
Cryotherapy is supposed to reduce inflammation caused by hard exercise and reduce pain by stimulating adrenaline and endorphins, which can cause feelings of euphoria or exhilaration.
Two systematic reviews by the internationally recognised and highly rated Cochrane Collaboration (http://www.cochranelibrary.com/) found that there was some evidence to show that cold-water immersion reduces delayed onset muscle soreness after exercise compared with rest or no intervention (Bleakley et al, 2012 http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD008262.pub2/full) or that there is insufficient evidence to determine whether whole-body cryotherapy reduces self-reported muscle soreness or improves subjective recovery after exercise compared with rest or no intervention (Costello et al, 2015 http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD010789.pub2/full).
There is some evidence to support subjects feeling better after cryotherapy but the evidence is not strong. However, these reviews did not research the physiological changes or lack of due to cryotherapy. The evidence on whether cryotherapy affects inflammation is equivocal with no consensus in the literature. But a possible mechanism of reduction of inflammation due to cryotherapy is by a reduction in metabolic activity caused by cooling and reduced arterial blood flow, for which there is some less than strong evidence.
It is quite possible that the beneficial effects, if there are any, are due to reduced subjective reports of pain i.e. the way it makes you feel. Reduction of pain/feeling exhilarated is of course useful if one has to train again after having trained hard (elite athletes or hard core amateur athletes undertaking multiple marathons on consecutive days for example). However, it maybe that there are no physiological beneficial effects of cryotherapy. And even if there is an anti-inflammatory effect due to reduced metabolism and reduced blood flow, is that a good idea? Inflammation is a normal part of healing. It is associated with pain but it is the begin stage of healing. Is anti-inflammatory treatment post training a good idea if it is achieved by reduction in metabolic activity and blood flow?
My suggestion based on the evidence is that there may be some small benefits in pain reduction for those training hard/competing hard with short turnaround time frames and where margin gains are all important. However, I would still caution against regular use of such a treatment if the mechanism is a reduction in metabolic activity and blood flow. I would also recommend that the amateur athlete looks at other ways to over-come post training soreness than use cryotherapy. For more details on cryotherapy and other ways to overcome post training soreness contact me here.