Immersing the body in a bath of cold water (cold water immersion) is a frequently used and popular way of recovery post exercise and as a result there has been a lot of scientific research into this area as an aide to improving recovery rates.
A recent review of cold water immersion (CWI) research by the British Journal of Sports and Exercise Medicine found that CWI has been found to be effective at reducing the rates of muscle soreness 24 and 48 hours after high intensity exercise for 60% of those taking part in the studies. The average decrease in the perception of soreness was 16%.
They found that cold water immersions was not effective at recovering muscles strength post exercise but it more effective in recovery of muscle power compared to doing nothing at all. In another study on 12 cyclists who performed five consecutive days of exercise including time trials and sprints, those who underwent CWI after each session had a higher average power output across the 5 days than those undergoing hot baths or no recovery therapy.
The exact mechanism in how CWI works is not known. Immersing the body in cold water (e.g. 10 minutes at 10C or 15mins at 15C) is thought to reduce blood flow in the muscle and surrounding tissue reducing inflammation caused by the strenuous exercise. This would help to reduce swelling which eases the perception of soreness. The reduction in muscle temperature may also slow down the effect of enzymes activated when muscle damage occurs.
If doing CWI at home for legs post cycling wear a warm top and hat to keep the upper body warm while immersing the legs. CWI may not be suitable for diabetics or those with circulatory problems who are strongly advised to consult with a doctor before doing it. Contrast water therapy is another water based therapy that has been found to be effective as a recovery strategy. This involves immersion for 1 minute in cold water (15C), followed by 1 minute in 38C water and each cycle is repeated 14 times. Harder to do at home unless you have two baths!
Regular postexercise cooling enhances mitochondrial biogenesis through AMPK and p38 MAPK in human skeletal muscle.
Brief intense interval exercise activates AMPK and p38 MAPK signaling and increases the expression of PGC-1alpha in human skeletal muscle.