Contrast Therapy 101: How to Actually Do It
Contrast therapy is having a moment. Alternating between heat and cold has become the headline wellness trend of 2026, and if you spend any time online, you have probably watched someone gasp their way out of an ice bath and into a sauna. It looks intense. It also looks a little confusing.
So here is the practical version.
How to actually do contrast therapy: how long to stay in each, what order to go in, and who should be careful.
Whether you are recovering from training or simply want to feel clear-headed again, this is the how-to guide we wish more people had before their first session. It is also one of the most-asked-about services at Flow Spa here in Peterborough, so we put the essentials in one place.
What Contrast Therapy Actually Does
Contrast therapy means moving back and forth between hot and cold on purpose. At Flow Spa that usually looks like time in the infrared sauna or hot tub followed by a cold plunge, repeated a few times.
The idea is simple. Heat opens your blood vessels and relaxes your muscles. Cold tightens those vessels back up. Going back and forth creates a pumping effect through your circulatory system, which many people find helps them feel refreshed and less stiff. There is also a nervous system side to it: the cold gives you a jolt of alertness, and the whole practice is a small, repeatable way to build resilience to stress.
Some research supports these benefits. A 2025 scoping review in the journal Medicina found that contrast therapy may help reduce pain, improve joint range of motion, and support functional recovery in musculoskeletal conditions. It is not a cure-all, but it is a genuinely useful recovery tool, which is a big part of why it has taken off.
The Basic Protocol: How Long and What Order
Here is a straightforward format that works well for most people to get the most benefits out of the experience:
Start hot. Spend some time warming up in the sauna or hot tub until you feel genuinely warm, not just sitting there. I like to do about 15-20 minutes.
Go cold. Move to the cold plunge for about 30 seconds to 3 minutes. Beginners can absolutely start at the shorter end.
Repeat. Alternate between the hot tub and cold tub back and forth for 3 to 4 rounds, or until you hit a total time in the cold of about 10 minutes.
Rest. Give yourself a few quiet minutes at the end to let your body settle.
A full contrast therapy session is an hour. This gives you plenty of time to relax in the sauna, alternate hot and cold tubs, and do the full circuit for a few rounds or finish back up in the sauna again.
A helpful rule of thumb for maximizing the benefits of cold exposure is to get 10-11 minutes of total time in the cold. If you can only handle 30 seconds or a minute at a time, that’s totally fine.
Should you end on hot or cold?
The common recommendation is to finish on cold if you want to walk out feeling alert and energized, which makes contrast therapy a great midday or post-workout reset.
If you are doing a session in the evening and your goal is to wind down, be mindful of timing. Finishing a cold plunge too close to bedtime can make it harder to fall asleep, so give yourself a few hours before you turn in, or lean toward finishing warm and relaxed instead. There is no single right answer here; it depends on what you want out of the session.
Tips for Your First Session
A few things that make the experience much better, especially early on:
Breathe slowly in the cold. The instinct is to gasp and tense up. Long, slow exhales help your body settle and make the cold far more manageable.
Ease into the cold time. Thirty seconds is a completely legitimate starting point. You can build up over several sessions.
Don't power through pain. Cold should feel bracing, not genuinely painful. Numbness or shivering that will not stop is your cue to warm up.
Hydrate. The heat portion makes you sweat more than you might expect, especially if you’re spending a good amount of time in the hot tub. We don’t notice ourselves sweating as much but research shows that hot tubs may be even more effective for heat exposure and raising core temperature than saunas are.
Let the last few minutes be quiet. Sometimes the most useful thing you can do afterward is simply sit and let your nervous system catch up.
Who Should Be Cautious
Contrast therapy is safe and enjoyable for most healthy adults, but the rapid temperature swings do ask something of your heart and circulatory system. Please check with your doctor first, or skip it, if any of these apply to you:
Heart conditions — heart disease, arrhythmias, a recent cardiac event, or uncontrolled high blood pressure
Pregnancy — both the heat and the cold immersion carry risks, so this is one to clear with your healthcare provider
Diabetes or reduced circulation — these can affect how well your body senses and regulates temperature
Cold-sensitive conditions — such as Raynaud's syndrome or cold urticaria
Recent stroke or other serious vascular issues
None of this is meant to scare you off. It is simply the honest version. If you are generally healthy and unsure, a quick conversation with your doctor is always a reasonable first step, and our team is happy to walk you through what a session involves before you commit.
Doing Contrast Therapy at Flow Spa
You can absolutely piece contrast therapy together at home, but part of what makes it sustainable is not having to manage the setup yourself. At Flow Spa in Peterborough, our infrared sauna, hot tub, and cold plunge are set up so you can move between hot and cold without thinking about logistics, then rest in a calm space between rounds.
It pairs naturally with the rest of a recovery routine, whether that is Normatec compression for tired legs or a focused reset before a busy week. If you are training for something, our sports recovery options are built with exactly this in mind.
Frequently Asked Questions
How long should a contrast therapy session be?
Most sessions run for an hour, made up of rounds of alternating hot tub, cold tub and sauna. We also have shorter, half-hour options for just sauna and cold plunge or hot tub and cold plunge when you’re short on time or want to get straight into the contrast.
What is the right hot-to-cold ratio?
A common guideline is to spend roughly three to four times as long in the heat as in the cold throughout the session. For example, around 3 to 5 minutes hot and 30 seconds to 2 minutes cold per round. It does not need to be exact. You can also flip this around if you’re trying to extend your time in the cold while still warming up in between rounds.
Should I finish on hot or cold?
Finishing on cold tends to leave you feeling alert and energized, which suits a daytime or post-workout session. In the evening, give yourself a few hours before bed or consider finishing warm so it is easier to wind down.
How often can I do contrast therapy?
Many people enjoy it once a week for an hour or even a few times a week when really needing recovery. Listen to your body, stay hydrated, and treat it as a recovery tool rather than something to push to extremes.
Is contrast therapy safe for beginners?
For most healthy adults, yes. Start with shorter cold exposures, breathe slowly, and never force yourself to stay in longer than feels okay. If you have a heart condition, are pregnant, or have circulation concerns, check with your doctor first. If you would rather have a hand your first time, our team can talk you through it before you start.
Can I combine contrast therapy with other recovery services?
Yes. It works well alongside compression therapy, massage, or a float session with combo appointment discounts. Our team can help you build a routine that fits how you actually feel.
Ready to Try It?
Contrast therapy is one of those things that makes a lot more sense once you have felt it. If you are curious, book a session at Flow Spa and let us guide you through your first hot-and-cold reset.
Need help finding the right time that works for you, or looking to book for multiple guests at once? Or give us a call at 705-230-8575, and we’ll be happy to help!
This article is for general information and is not medical advice. If you have a health condition, please talk with your healthcare provider before trying contrast therapy.