How Long Should Contrast Therapy Last?

How long should contrast therapy last? Plan on 25 to 55 minutes, start to finish, and 85 if you want to go slow or share the suite with a friend. That covers a few minutes to settle in, rounds of sauna and cold plunge, and a shower at the end. The research has reassuring news, too: with contrast therapy, longer isn't automatically better.

Below: what the studies found about session length, how 25, 55 and 85 minutes play out round by round, and how to pick yours. Want the minutes inside each round? Read how long to stay in the sauna and cold plunge.

What the research says about session length

The best data on contrast session length comes from sports science. At the Australian Institute of Sport, researchers had trained athletes alternate 1 minute in hot water (around 100°F) with 1 minute in cold (around 58°F) for 6, 12 or 18 minutes, starting 10 minutes after a hard workout. Two hours later, they tested them again.

• Cyclists. In 11 trained cyclists, 6 and 12 minutes helped performance in the second session compared with resting, and every version eased fatigue and soreness. Eighteen minutes did no better than the shorter options (European Journal of Applied Physiology, 2011).
• Runners. In 10 trained runners, 6 minutes helped their second 3,000-meter run compared with resting, while 12 and 18 minutes added nothing extra (International Journal of Sports Physiology and Performance, 2012).

The big reviews add the wider picture:

• Contrast water therapy, 18 trials: better than passive rest for muscle soreness and strength loss in the four days after hard exercise, though the trials were small and at high risk of bias (PLoS One, 2013).
• Team sports, 23 studies and 606 athletes: cold water immersion helped several recovery measures, and contrast water therapy helped athletes feel less fatigued (Journal of Strength and Conditioning Research, 2017).
• Cooling after exercise, 36 studies: cooling, especially cold water immersion, eased muscle soreness at 24, 48 and 96 hours compared with doing nothing (PLoS One, 2015).

On the heat side, a randomized trial of 47 inactive adults found that adding a 15-minute sauna after exercise for eight weeks improved fitness and lowered systolic blood pressure more than exercise alone (American Journal of Physiology, 2022).

Those studies used tubs of water and a traditional sauna, so they don't map minute for minute onto a CBR session. The takeaway still holds: a focused session of reasonable length can do plenty. Pick the length that fits your day.

How long the heat and the cold should last

• Cold. A meta-analysis of nine trials found the best soreness results at about 52 to 59°F for 11 to 15 minutes (Sports Medicine, 2016). Our plunges are kept at 45 to 49°F, far colder, so the same principle points to much shorter dips: 30 seconds to 3 minutes.
• Heat. In the Finnish heart study of 2,315 men, sauna sessions longer than 19 minutes were linked to a lower risk of sudden cardiac death than sessions under 11 minutes. It's observational, so it shows a link, not proof (JAMA Internal Medicine, 2015).
• The split. Lab protocols mostly run from 1 minute of heat per minute of cold to 4 minutes per minute. A 2020 study used 4 minutes of infrared heat to 1 minute of cold for four rounds and found bigger changes in forearm blood flow than with hot and cold water baths (Medical Science Monitor, 2020). Sauna routines stretch the heat much further, 10 to 20 minutes against 30 seconds to 3 minutes in the plunge. Few studies compare splits head to head, so choose the one that feels good.

What fills a contrast therapy session

Whatever length you book, a session has the same four parts:

• Settling in. Bag down, phone away, lights set the way you like. Two to five minutes.
• Heat. Time in the infrared sauna, the longest part of each round.
• Cold. A short stay in the cold plunge, from 30 seconds to a few minutes.
• Shower. Rinse off, towel off, get dressed. It takes longer than you think.

A round is one stretch of heat followed by one dip in the cold.

How 25 minutes plays out

The quick reset. Good before work, on a lunch break or after a lift. Expect one full round and a short second one.

• 0:00 Settle in (2 min)
• 0:02 Sauna (12 min)
• 0:14 Cold plunge (up to 2 min)
• 0:16 Back in the sauna, shorter this time (5 min)
• 0:21 One last dip, or skip it (1 min)
• 0:22 Shower and go (3 min)

How 55 minutes plays out

The full session, and the one we suggest for a first visit. Two or three rounds without watching the clock, and a shower you don't have to rush.

• 0:00 Settle in (3 min)
• 0:03 Sauna (15 min)
• 0:18 Cold plunge (2 min)
• 0:20 Sauna (12 min)
• 0:32 Cold plunge (2 min)
• 0:34 Sauna (10 min)
• 0:44 Cold plunge, or finish warm (2 min)
• 0:46 Shower (9 min)

How 85 minutes plays out

The long unwind. Three slow rounds, ten quiet minutes to sit, and a shower with nowhere to be.

• 0:00 Settle in (5 min)
• 0:05 Sauna (18 min)
• 0:23 Cold plunge (3 min)
• 0:26 Sauna (15 min)
• 0:41 Cold plunge (3 min)
• 0:44 Sauna (15 min)
• 0:59 Cold plunge (3 min)
• 1:02 Sit and breathe (10 min)
• 1:12 Shower (13 min)

These are examples, not instructions. Every session is self-guided, so swap, shorten or skip anything you like.