Paula Radcliffe may say they are the secret of her success, but Australian research is questioning the benefits of taking an ice bath after exercise.
Physiotherapists recommend the bath as a way to speed up recovery, claiming the icy cold helps shift lactic acid.
But this is unproven, and a study in the British Journal of Sports Medicine now claims the opposite may be true.
Out of 40 volunteers, those who took an icy plunge reported more pain after 24 hours than those who took a tepid bath.
Ice baths have become one of the most fashionable ways of recovering after an intense game or marathon. From rugby to tennis players, the bath has a series of celebrity endorsers.
The theory is that the icy cold causes the blood vessels to tighten, and drains the blood along with waste products such as lactic acid out of the legs.
When Jonny Wilkinson or Paula Radcliffe emerge from the bath, their limbs fill up with fresh blood which invigorates the muscles with oxygen and helps the cells repair.
Although physiotherapists who promote the bath have had little evidence to prove this, there is plenty of anecdotal evidence from the athletes themselves that the bath makes them feel better.
Source - BBC