One of the S&C coaches that I'm mentoring recently asked me the thinking behind contrast bathing, alternating between hot and cold. Here is a brief overview of the main theories and some recent research. For detailed review of how contrast bathing and other recovery strategies fit into your overall training programme check out The Strength and Conditioning Bible.
Ideally you are looking to immerse your body in water. Failing that you can use a shower (I've personally found this pretty useful, especially if the shower head can be removed from the wall as it allows you to target the areas that have been working). I'm sure this helped me when I was snowboarding a couple of years ago in Austria. Exact mechanisms remain unclear but it has been suggested that alternating hot and cold showers/baths provides an increase in blood flow to the working muscles (due to vasodilattion and vasoconstriction) and accelerates the removal of lactic acid. It has also been suggested that contrast bathing stimulates the nervous system because the brain has to receive and recognise two different types of information (hot and cold). The changes in temperature may also help to increase arousal (the cold blast of water on a naked body certainly wakes you up!).
Complete within 30 minutes of training/competition
Water Temperature: Hot - 35-40 degrees Celsius, Cold 10-15 degrees Celsius the closer you can get to these temperature the greater the contrast but sometimes you just have to make do with what you can get. Whilst in China with their National Team we just couldn't get really cold water.
Shower - hot 1-2 mins, cold 30-60 secs (repeat 3-4 times) Bath/Spa - hot 3-4 mins, cold 30-60 secs (repeat 3-4 times)
Bath - cold 30-60 seconds immersion, followed by 60 seconds dry rub (vigorously rub the cooled areas) with a towel (repeat 2-4 times)
Bath - cold 30-60 seconds immersion, followed by 60 seconds out of the water towel dry (repeat 3 times)
Begin and end with cold
Here are a couple reviews I've put together from two studies published 2008 looking at the effects of contrast bathing.
The Effects of Contrast Bathing and Compression Therapy on Muscular. Medicine and Science in Sports and Exercise 2008: 40 (7) 1298-1307
Recovery and regeneration is big news with more and more people realising that recovery from training is far more important than the training itself! Hot on the heels of this increased awareness is an increase in research papers exploring the efficacy of various recovery and regeneration strategies.
Much of the current literature in the field of soft-tissue regeneration has been conducted using untrained populations and therefore does not reflect the recovery responses of trained athletes who are less susceptible to delayed onset muscle soreness (DOMS) and/or exercise induced muscle damage. Researchers based in the North East of England (big up to my man Duncan French who was behind this piece of research!) have recently evaluated the efficacy of two of the most talked about recovery strategies; Compression clothing, and contrast bathing.
Baseline values of muscle soreness, serum creatine kinase (CK) and myoglobin (Mb), joint range of motion, limb girth, 10- or 30-m sprint, countermovement jump (CMJ), and five repetition maximum squat were completed by 26 male subjects. They then undertook what the researchers like to call 'a resistance exercise challenge (REC)' with the sole purpose of inducing muscle damage! The REC consisted of 6 x 10 parallel squats at 100% body weight with 5-s one repetition maximum eccentric squat superimposed onto each set.
After the REC, subjects were separated into three intervention groups: contrast bathing (wearing only shorts, subjects alternated between cold (8-10 degrees Celsius) and hot (37-40 degrees Celsius) water baths, starting and ending with cold immersion for a total of four cold and three hot baths. They remained in the cold water for 60 s and the hot water for 180 s, alternating immediately between the two, compression clothing (subjects were instructed to wear commercially available full-length (i.e., ankle to waist) compression tights made of a composite Lycra and Meryl microfiber (Skins, Campbeltown, Australia) for 12 h, overnight and, control. Forty-eight hours after REC, the subjects exercise performance was reassessed. Creatine kinase and myoglobin were also measured +1, +24, and +48 h post-REC.
This current research study calls into question the effectiveness of contrast bathing and compression clothing. This fits with the recovery pyramid which I first wrote about back in 2006. The recovery pyramid highlights the need to establish the fundamental recovery strategies such as adequate sleep, nutrition and training before considering the use of interventions such as contrast bathing and compression clothing which remain misunderstood and overemphasised.
The effect of contrast water therapy on symptoms of delayed onset muscle soreness. Journal of Strength and Conditioning 2007: 21 (3) 697-702
The researchers found that although within-groups differences were observed in physiological, physical, performance and perceptual measures after these recovery activities, there was little evidence to indicate contrast bathing and/or compression clothing are any more effective than passive rest at improving recovery and regeneration in trained athletes.
Exact guidelines don't exist but this a protocol I've used whilst working with various athletes from a range of sports. If you work with heavier athletes I would suggest you get them in and out of hot/cold baths to make sure you can achieve the desired amount of cooling/heating.
I always like to present a balanced view of the current research (wouldn't it be easy of everyone just agreed!) and whilst the first review may have cast some doubt as to the efficacy of contrast bathing as a recovery intervention a multinational research team from New Zealand and the UK would beg to differ.
This study looked at the effect of contrast water therapy (CWT) on the physiological and functional symptoms of delayed onset muscle soreness (DOMS) following DOMS-inducing leg press exercise. Thirteen recreational athletes (male and female) took part in the study and performed 2 experimental trials separated by 6 weeks in a randomised crossover design. In this study muscle damage was induced by performing a leg press protocol consisting of 5 x 10 eccentric contractions (180seconds recovery between sets) at 140% of 1 repetition maximum (1RM). This was followed by a 15-minute recovery period incorporating either CWT (subjects immersed their lower body alternately between 2 baths â€” immersion for 60 seconds in cold water (8-10 degrees Celsius) followed immediately by immersion for 120 seconds in hot water (40-42 degrees Celsius), alternating between the 2 baths for a total of 15 minutes) or no intervention, passive recovery (PAS) (PAS where subjects sat with minimal movement for 15 minutes).
The results from the study showed that contrast water therapy was associated with a smaller reduction, and faster restoration, of strength and power measured by isometric force and jump squat production following DOMS-inducing leg press exercise when compared to PAS. Therefore, CWT seems to be effective in reducing and improving the recovery of functional deficiencies that result from DOMS, as opposed to passive recovery. Based on the evidence from this study CWT appears to be a recovery strategy that could easily be adopted and integrated into athletes' recovery programs.
So why did the recovery strategy in this study work? It may be because the recovery protocol used in this study differed slightly from the one used in the first study. Working as a conditioning coach I know that there are a wide range of protocols currently being used by practitioners. What these two studies show is that even a slight difference in water temperature and duration of immersion may have an impact on recovery. Could sitting in slightly hotter water for less time actually make a difference?
Cold (8-10 degrees Celsius) - 60 seconds
Hot (37-40 degrees Celsuis) - 180 seconds
Cold (8-10 degrees Celsius) - 60 seconds
Hot (40-42 degrees Celsius) - 120 seconds
Whilst this study showed improvements in the recovery profile to support CWT as a practical and low-cost recovery strategy it is clear that more research to identify exact protocols is required. Until then the debate will continue and I will be on the look out to and will keep you updated.