Heat, Cold, and Recovery—What Contrast Therapy Actually Does

In October of 2024, my brother Derek and I summitted Grand Teton with some friends. We had typically spent three days on the mountain on prior trips—hike to base camp on day one, summit and back to camp on day two, hike out on day three—but this trip we completed over just two days. And day two was a bear: up before 4 AM, summit, back to camp to pack up, then all the way out to the vehicles. When we finally reached the trailhead around 8 PM, my legs were thoroughly smoked.

I did what I could for recovery that evening—drank plenty of fluids, ate a good dinner with some extra salt, and got a reasonable night’s sleep in a real bed. Still, cramping calves and quads woke me up at least once.

Fortunately, we had a special recovery session planned for the following day—a date with a pop-up sauna and a cold plunge that one of the guys in the group had brought along.

After breakfast, we slowly made our way outside to get the wood stove going in the sauna and fill the cold plunge with water and ice. Then we did two rounds of “contrast therapy”: about 45 minutes in the sauna followed by 3 minutes in the cold plunge, plus another 30 minutes in the sauna followed by 2 minutes in the cold plunge.

I had sat in saunas numerous times before that, but it was my first experience in a cold plunge. While I was not exactly looking forward to spending multiple minutes submerged up to my chin in water with floating ice, it ended up being far less terrible than I’d expected—and I felt genuinely good afterward. Certainly not back to normal; my legs were still clearly tired. But they felt good in a way that I can only describe as “fatigued, but springy”.

And that brings me to the point of today’s tip: There’s a lot of noise around cold water immersion (CWI) and contrast therapy. Some of it is just hype, and some is actually well-supported. Here’s where the research points on all of it.

What the research actually shows

CWI has been well-studied for recovery, and the results are legitimately good. A 2025 meta-analysis covering 55 randomized controlled trials found that CWI effectively reduces delayed-onset muscle soreness (DOMS) and lowers creatine kinase levels (a marker of muscle damage) after exercise.

What makes the research more interesting than the typical influencer version of the story is that the optimal protocol isn’t extreme. The evidence points to 10–15 minutes at roughly 11–15°C (approximately 52–59°F), which is cool-to-cold tap water, not ice bath territory. Extreme temperatures aren’t meaningfully more effective than moderate ones. (So the cold plunge filled with floating ice cubes that we used after Teton? Probably more dramatic than necessary—though I don’t regret it.)

The research also shows that combined therapy—pairing heat and cold—outperforms CWI alone. This almost certainly explains why I felt as good as I did: the contrast between extended sauna time and the cold plunge likely did more than either would have in isolation. The alternating vasodilation (blood vessel dilation) from heat and vasoconstriction (blood vessel constriction) from cold appears to improve circulation and help clear metabolic waste more effectively than one modality by itself.

That said, the picture is slightly more nuanced for women. A 2025 randomized controlled trial found that CWI alone produced no significant recovery benefit for women compared to a control group—though the study tested cold and heat in isolation, not contrast therapy, so it doesn’t speak to the combined protocol. It’s also a single study—which isn’t as robust as a meta-analysis—and not the final word.

Still, sports scientist Stacy Sims has separately noted that extreme cold can significantly elevate cortisol in women, which is particularly unhelpful during periods with already high fluctuations of hormones (such as perimenopause). So that could be a possible mechanism for why cold alone underperforms.

A note on strength training and hypertrophy

While we’re dealing with nuance, there’s another well-established finding in the recovery literature worth mentioning here: regular CWI immediately following weight training may blunt hypertrophy (muscle growth) adaptations over time. The mechanism is the inflammatory response that cold helps quiet—that same response is also part of the signal that drives muscle growth. Consistently suppressing it can reduce related long-term gains.

This doesn’t mean CWI and weight training can’t coexist. After all, context matters and goals change. So if you’re newer to training and are interested in reducing DOMS (the soreness that occurs 24-48 hours after doing something you haven’t done for a while)—or if muscle growth isn’t your primary goal—CWI or contrast therapy is likely to help. Just remember to consider the implications if the primary objective from your gym sessions is building muscle.

Putting it into practice

You don’t need a wood-fired pop-up sauna or a cold plunge full of ice to get meaningful benefit from contrast therapy.

If you have access to a sauna^†, steam room, or hot tub: Consider spending 15–20 minutes in the heat before transitioning to a cool shower (or cold plunge if it suits you) for 2–3 minutes after a gym session, competition, or other long-duration event. You can repeat the cycle a second time if you like.

If you don’t: End your regular shower with 2–3 minutes of cool water. It’s simple and, based on most research, probably all that you need. (Although it’s not quite as memorable as a wood-fired sauna and cold plunge on the backside of a Grand Teton summit.)

Either way, the evidence suggests the combination of heat and cold is where most of the benefit lives—not cold alone, and not more extreme than it needs to be.