by Cold plunges are everywhere… in gyms, influencer feeds, podcasts, to full blown built in cold plunge tubs set up in people homes. They’ve gone from niche recovery tool to full-blown status symbol, complete with slow-motion reels and motivational captions. But there’s one thing nobody’s filming: what they might be doing to your actual progress.
A new study out of Maastricht University puts a spotlight on something that’s been mostly glossed over. The impact cold exposure has on muscle growth. And if you’re hitting the weights to build size or strength, the news isn’t exactly chill.
The Setup: One Workout, Two Legs, Very Different Outcomes
In the study, twelve active men performed a lower-body resistance workout. Immediately after, each participant submerged one leg in cold water (8°C / 46°F) and the other in thermoneutral water (30°C / 86°F) for 20 minutes. After the soak, they consumed a drink with amino acids and carbs. Essentially a recovery shake, but with a twist: it included a tracer to track how effectively the body absorbed and used the protein.
Researchers then monitored blood flow in the quads and took muscle biopsies several hours later.
The Results: Cold Legs Got Left Behind
The leg exposed to cold water had significantly reduced blood flow compared to the warm-soaked leg. Both immediately after immersion and even hours later. And that reduced circulation came at a cost: less amino acid uptake, and therefore less muscle protein synthesis.
Translation: the cold-treated leg didn’t make nearly as much use of the recovery shake. Fewer nutrients reached the muscle, which likely blunted the repair and growth process.
To make matters worse for cold plunge fans, the degree of reduced protein incorporation closely matched the drop in blood volume. The link was strong enough that the researchers believe the cold exposure alone could explain the reduced gains.
So… Should You Quit Cold Plunges?
Not necessarily, it depends on your goals.
For endurance athletes or people managing post-exercise inflammation, cold exposure still has value. Ice baths can reduce soreness and perceived fatigue, making them useful tools after long runs, intense games, or back-to-back training sessions.
But if you’re lifting to build muscle? That immediate post-workout soak might be working against you.
Brad Schoenfeld, one of the most respected voices in hypertrophy research, backed up these findings. He pointed to earlier research showing that ice baths could hinder muscle growth and noted that this latest study confirms one likely reason why: protein uptake drops when blood flow is restricted.
What Now?
This was a small, tightly controlled study. The sample size was modest, and the conditions were extreme. Most people aren’t dunking just one leg in ice water while sipping precision-engineered protein shakes.
Still, if your main focus is maximizing growth after resistance training, the timing of your cold plunge could matter more than you think. Waiting a few hours after your session might let you hold on to the recovery benefits without disrupting muscle repair.
In short, that post-workout ice bath photo might look cool on Instagram, but if it’s size you’re after, warming up might be the better play.
