Should I use heat or ice for sore muscles?

For ordinary delayed-onset soreness two days after a hard session, heat is the better call. It raises local blood flow and makes tissue more pliable, which is what stiff, sore muscles actually need. Save cold for acute swelling in the first 24 to 48 hours after an injury or for a fast turnaround between competition efforts.

Does a cold plunge block muscle growth?

It can blunt it if the timing is wrong. Regularly plunging within an hour or two of strength training dampens the inflammatory signalling that drives adaptation, and a 2024 meta-analysis found that plunging straight after resistance training may reduce muscle growth, although the studies were rated fair to poor quality. If you love the plunge, put it on rest days or several hours away from lifting.

How long should a sauna session be?

Most people do well with 15 to 20 minutes at a comfortable temperature, two to four times a week, with water before and after. Longer is not better. If you feel lightheaded, get out. Sauna is heat stress, and stress still needs to fit inside your weekly recovery budget.

Do I need either one to recover well?

No. Sleep, protein, easy movement, and a training week that includes genuinely light days will outperform every tub and every infrared panel in the city. Heat and cold are pleasant additions once the basics are handled. If you want a coach to build the basics with you, start with a movement assessment .

Sauna or Cold Plunge? A Coach's Guide to Heat, Cold and Recovery

Vancouver has never had more plunge tubs and infrared rooms. Here is the short version of what each one does, and the far more useful question of when to use it.

Every second gym in Vancouver now has a plunge tub, an infrared room, or a friend who will tell you exactly which one changed their life. Both work. Neither works all the time. The useful question is not sauna or cold plunge, it is what you are trying to do in the next 24 hours.

What Cold Actually Does

Cold water immersion narrows blood vessels, slows local metabolic activity, and reduces nerve conduction speed. Practically, that means less swelling, less perceived soreness, and a body that feels calmer than it did five minutes ago. The effect on pain is real and it is fast.

What cold does not do is speed up repair. It suppresses the inflammatory response, and inflammation, in a training context, is not the enemy. It is the message. When you lift heavy and create micro-damage, the inflammatory cascade is what recruits the repair machinery that leaves you stronger. Quench the signal and you quiet part of the adaptation.

This is why the research on regular post-lifting cold immersion points the same way: athletes who plunge may feel better in the short term but may build slightly less muscle over a training block. Feeling recovered and being recovered are not identical.

A 2024 meta-analysis of eight studies found that cold water immersion straight after resistance training may reduce muscle growth. The authors rated the studies fair to poor quality, so treat it as a caution rather than a verdict.²

What Heat Actually Does

Heat runs the opposite direction. Blood vessels widen, local circulation rises, and connective tissue becomes more pliable, which is why a warm body moves through range more easily than a cold one. Sauna also produces a mild cardiovascular load: heart rate climbs, plasma volume adapts over weeks, and most people report the same nervous-system downshift they get from a long walk.

For everyday training soreness, heat is usually the better answer. That stiff, dull, two-days-later ache is not swelling. It is tissue that wants blood flow and gentle movement, and a warm shower plus ten minutes of easy mobility beats an ice bath almost every time.

The Decision, Simplified

Fresh injury, visible swelling, first 24 to 48 hours. Cold, in short bouts, alongside a call to your physio.
Two hard efforts in the same day or on back-to-back days. Cold. You are buying performance tomorrow and accepting a smaller adaptation.
Normal soreness after a hard week. Heat, easy movement, and food.
Before training, especially in a Vancouver February. Heat, then a proper warm-up. Heat is not a warm-up on its own.
A training block where the goal is building muscle. Keep cold at least four to six hours away from lifting, or move it to rest days.

Contrast Therapy and the Honest Answer

Alternating hot and cold feels excellent, and there is some evidence it helps with soreness too. A 2018 meta-analysis of 99 studies found contrast water therapy was among the recovery methods that reduced delayed onset muscle soreness after exercise, alongside massage, compression garments, cold water immersion and active recovery, with massage the most effective.¹ If contrast rounds are the thing that gets you to spend twenty quiet minutes not looking at your phone, that is a legitimate reason to do them. Just do not let them displace the parts of recovery that carry the load.

Because here is the part nobody sells tickets to: the largest recovery levers are unglamorous. Seven to nine hours of sleep. Enough protein spread across the day. One or two genuinely easy sessions each week. A stress load that is not permanently redlined. We wrote the full breakdown in our recovery guide for CrossFit athletes, and the Sleep Reset covers the single biggest one.

How We Coach It at CrossFit BC

On the floor in Olympic Village, the conversation almost never starts with tubs. It starts with the training week. If somebody is stacking five hard days and asking whether cold plunging will fix how they feel, the answer is that a lighter Wednesday will fix more of it, faster, for free.

Once the week is sane, heat and cold become useful dials. Members racing a HYROX event with multiple efforts in a weekend use cold deliberately, between efforts, because performance in six hours matters more than adaptation in six weeks. Members in a strength block keep the plunge for Sundays. Same tools, different jobs.

If your recovery has felt like guesswork, that is usually a programming problem rather than a temperature problem. Come in for a movement assessment and we will look at the week first.

References

Dupuy O, Douzi W, Theurot D, Bosquet L, Dugué B. An evidence-based approach for choosing post-exercise recovery techniques to reduce markers of muscle damage, soreness, fatigue, and inflammation: a systematic review with meta-analysis. Frontiers in Physiology, 2018;9:403. https://doi.org/10.3389/fphys.2018.00403
Piñero A, Burke R, Augustin F, et al. Throwing cold water on muscle growth: a systematic review with meta-analysis of the effects of postexercise cold water immersion on resistance training-induced hypertrophy. European Journal of Sport Science, 2024;24(2):177-189. https://doi.org/10.1002/ejsc.12074

A 2026 original rewrite of a topic first covered on Dai Manuel's archive. Coaching guidance, not medical advice.