Researchers warm to effectiveness of ice baths

For most of past century, soccer players, athletes and other footballers would cool down by warming up.

The hot bath after a game was an unquestioned ritual.

More recently, the hot water has been replaced by cold.

Athletes know that in the days after great physical exertion, their muscles get sore, but they believe that pain will be lessened if they immerse themselves in ice cold water immediately after exercising.

And now, an international team of researchers has confirmed the effectiveness of cold water immersion therapy in stopping muscle pain.

Some in the field, however, are still sceptical.

"It tends to be effective, at least compared to other means that are used. Maybe not in terms of a specifically strong sense but at least in the way that's meaningful," said Professor Ty Hopkins from Brigham Young University in the US state of Utah.

Professor Hopkins, who specialises in sports medicine and exercise science, was one of the authors of the study into the effectiveness of cold water immersion therapy.

"Not only did the subjects feel better but there were actually signs that tissue damage was decreased," he said.

In their review, the authors compared 17 small trials involving 366 people.

They included people who were asked to get into cold water after running, cycling and resistance training.

And they found a significant reduction in muscle soreness in the four days after exercise.

"Maybe for those who border on endurance sports and higher workout times at least or intensities, they might dabble into it and see how it works for them," Professor Hopkins said.

He says any water under 15 degrees Celsius will be somewhat effective.

"And the time can really vary depending on the tissues," he said.

Importantly, the study did not compare the effects of cold water with other interventions like light jogging or using compression stockings, so the researchers cannot say which technique would be the most effective.

They also cannot say what harmful side effects might flow from cold water immersion.

"Certainly some people could be hypersensitive to cold which could allow them to have a skin or even an allergic type of reaction," Professor Hopkins said.

There is also the risk that the therapy simply will not work at all.

Dr Shane Brun, an Associate Professor of musculoskeletal and sports medicine at James Cook University, says most of the studies are poor quality.

"There's not a lot of evidence so far that cold water immersion does a lot for physical benefits of people using it," he said.

Dr Brun says placebo effect may be playing a role.

"Without a doubt, a significant aspect of how well an athlete performs is basically what's going on between their ears," he said.

"If an athlete has confidence, belief, mental strength, that has a significant impact in how they perform."

That does not mean Dr Brun wants athletes to steer clear of the technique.

"If you were to ask me, what I prefer an athlete doing ice water baths or using anabolic steroids it's an open misere, I mean my answer's going to be jump in a cold bath rather than take any supplements," he said.

Dr Brun says in many cases, all that matters is that the athlete believes the cold water is doing them good.

He says the same can be said for stretching after exercise.

The physical evidence suggests stretching does not do much to help the body recover, but if you believe it is helping, then it probably will.