Contrast routines come in many versions: three rounds or five, end on cold or end on hot. The controlled trials give a clearer starting point than most of them.
This article lays out the protocols used in trials and sets them beside the home limits our sources give. It sits under our overview of contrast therapy benefits. It is general information, not medical advice.
Short answer: trials typically used 1 minute in cold water at about 11°C (52°F), then 1 to 3 minutes in hot water at 35.5 to 45°C, repeated 3 to 7 times for 6 to 24 minutes. One trial found no difference between 6, 12, and 18 minutes. At home, keep cold rounds within Cleveland Clinic’s limits and hot tub water at or below 104°F.
The protocols in the trials
According to the 2013 meta-analysis by Bieuzen and colleagues in PLOS One, the 18 trials it pooled used short, repeated rounds. Cold water ran 8 to 15°C, averaging 11.1°C. Hot water ran 35.5 to 45°C, usually for 1 to 3 minutes. Three trials used warm showers instead of a hot bath.
| Trial (as listed in the 2013 review) | Cold | Hot | Rounds |
|---|---|---|---|
| Vaile 2010 | 1 min at 8 to 10°C | 2 min at 40 to 42°C | 5 |
| Vaile 2008 | 1 min at 15°C | 1 min at 38°C | 7 |
| Dawson | 1 min at 12°C | 2 min at 45°C | 4 cold, 5 hot |
Total time ran about 6 to 24 minutes. Most trials used one session after a single workout.
Does session length matter?
One trial in the review, by Versey and colleagues, compared 6, 12, and 18 minutes of contrast therapy. It found no difference in soreness between them. That suggests a short session did as well as a long one in that study.
End on hot or cold?
The trials varied. Some ended cold, some hot, and the review didn’t identify a better order. Any rule you see about “always end on cold” isn’t from these trials.
How trial numbers compare with home limits
| Trials (2013 review) | Home guidance | |
|---|---|---|
| Cold water | 8 to 15°C (46 to 59°F), 1 min per round | Cleveland Clinic: start at 50 to 59°F, a minute or two, never over 5 minutes, never below 40°F |
| Hot water | 35.5 to 45°C (96 to 113°F) | CPSC: hot tub water never above 104°F |
| Sauna | Not tested | Cleveland Clinic: start at about 5 minutes, build to 15 to 20 |
The Fahrenheit conversions are our arithmetic. Note the hot side: the top of the trial range is above CPSC’s 104°F hot tub ceiling.
Limitations
None of these trials used a sauna. Every trial in the 2013 review was rated high risk of bias, and most were small and mostly male. The review says optimal temperatures and durations remain undefined.
Here’s what the spec sheet won’t tell you. A chiller that cools to 39°F, like the Renu Cold Stoic 2.0, can go colder than any trial used. The coldest trial water was 8°C, about 46°F.
My rule of thumb: borrow the trial structure, short cold rounds and a few repeats, but keep each temperature inside the home limits above.
Bottom line: trial protocols were short, 1 minute cold and 1 to 3 minutes hot, repeated 3 to 7 times, and longer sessions didn’t help in the one trial that tested it. For what contrast therapy can and can’t do, see the contrast therapy benefits overview linked above.
Sources
- Bieuzen F, Bleakley CM, Costello JT, “Contrast Water Therapy and Exercise Induced Muscle Damage: A Systematic Review and Meta-Analysis,” PLOS One, 2013: pmc.ncbi.nlm.nih.gov
- Cleveland Clinic, “Are ‘Cold Plunge’ Ice Baths Good for You?” May 8, 2026: health.clevelandclinic.org
- Cleveland Clinic, “Get Your Sweat On: The Benefits of a Sauna,” August 12, 2024: health.clevelandclinic.org
- U.S. Consumer Product Safety Commission, “CPSC Warns Of Hot Tub Temperatures,” release 79-071, December 31, 1979: cpsc.gov