Athletes who since the time of the ancient Greeks have plunged into icy water after intense exercise are not getting any benefit and might even be putting their health in danger, according to new research.
Scientists at the University of Portsmouth found cold water immersion was no more and no less effective in helping an athlete recover after sport than light cool-down exercise.
They also warn the practice of plunging into ice baths, common among elite athletes, might do more harm than good.
Lead author Jo Corbett said: “Ice baths are frequently used by sportsmen and women to help them recover after exercise but our results show they don’t work. They also pose a number of potentially serious health risks.
“If people using ice baths are receiving no real benefit then they should be probably be advised to stop using them.”
The study is published in the European Journal of Sport Science.
Among those known to favour the practice of plunging into water colder than 15 degrees Celsius are marathon runner Paula Radcliffe and the England rugby team.
Cold water has been thought to reduce inflammation, swelling, and muscle spasms and therefore pain, meaning an athlete can perform again at high level more quickly.
Dr Corbett said: “Cold water immersion has been used since Greek and Roman times. A book from 1715 suggests cold water immersion functions as a ‘diuretic, anti-hypnotic, antidote against opiates and as treatment for a variety of conditions including sleepy distempers, inflammations, pains, rheumatism, and convulsions’.
“The practice has become increasingly popular in recent years thanks largely to high profile sportsmen and women doing it, but how it helps has never been entirely clear and the reasons given are largely speculative.
“The findings of our study do not support it as the most effective way of speeding up recovery. It might be that previous studies have used as a control group athletes who do nothing to warm down versus those who are immersed in cold water.
“We found athletes who cooled down using light exercise recovered at the same rate as those in cold water.”
The scientists tested 40 male athletes after 90 minutes of intermittent shuttle running. After running, the men were divided into groups with 10 stood in cold water for 12 minutes; 10 stood in warm water for the same period; 10 sat in cold water for two minutes; and ten walked slowly for 12 minutes.
Muscle performance was measured before exercise and afterwards at 12 hours, a day, two days and five days.
No differences were found between any of the groups in terms of athletes’ perception of pain or in their biochemical markers of muscle cell damage.
Dr Corbett said: “The rigours of sport can require people to train and compete at an intense level so there is considerable interest in finding ways of increasing the amount of training they can do and in improving recovery time and thereby increasing performance.
“But it is clear from this study that water immersion, whether in traditional ice baths or in warm water, sitting or standing, does nothing to improve recovery time compared to traditional cool-down light exercise.
“Indeed, research is increasingly pointing towards cold water immersion as posing a possible threat to people’s health.”
The research team suggest further studies need to be done to reconcile conflicting findings from a number of studies and to establish if cold water immersion is ever effective given the potential dangers associated with it.
