Do Ice Baths Reduce Muscle Growth?

Is it a good idea to immerse yourself in a tub of cold water after a workout?

That’s a question that popped up in my inbox the other day. Here’s what it said:

“One thing I’ve tried to find more about is cold water immersion after training and whether it’s actually beneficial or not. I see a lot of athletes and celebrities doing it to help with recovery. Will it help?”

The research on post-exercise cold water immersion is a bit of a mixed bag.

There is evidence to show that cold water immersion can help reduce post-exercise muscle soreness [2], improve your mood, enhance the adaptations to endurance exercise [3], and accelerate recovery during periods of intense training [4].

That’s the good news.

The bad?

There’s a growing body of research to show that post-training cold exposure can interfere with gains in strength and size. By interfering with your body’s natural response to exercise, you may well end up slowing your progress rather than speeding it up.

What’s more, any recovery-enhancing benefits of ice baths may have a lot more to do with the extent to which you believe in their effectiveness than their ability to generate significant physical changes in your body.

More on that in a moment.

First, here’s a closer look at what science has to say on the subject of ice baths and muscle growth.

Ice Baths and Muscle Growth

In a 2015 study published in the Journal of Physiology, Australian researchers took a group of 21 volunteers and got them to train their legs twice a week for a total of 12 weeks [1].

Half the group jumped into an ice bath for 10 minutes after their workout. The other half spent the same amount of time cycling on a stationary bike.

Although both groups gained muscle, subjects who cycled for 10 minutes after training made three times greater gains in muscle mass compared with those in the ice bath group.

In a similar trial, researchers from Melbourne’s Victoria University got two groups of men to lift weights three days a week for seven weeks [5].

Both groups followed the same training program, but with one important difference.

Five minutes after each workout, the first group sat in a cold (10 degrees C) bath for 15 minutes. Group two, on the other hand, sat in a room where the temperature was maintained at a comfortable 23 degrees C.

Once the 7-week training program was complete, the researchers extracted a slice of tissue from the thigh muscles of each of the men, to see how it compared with a similar slice of tissue taken at the start of the study.

The result?

Cold water immersion appeared to put the brakes on muscle growth, with the passive recovery group – the guys who sat in a chair for 15 minutes after each workout – posting the biggest increase in the size of their fast-twitch muscle fibers.

Here’s how the researchers describe their findings:

“Taken together, these observations suggest cold water immersion may shift post-exercise muscle protein balance towards reduced protein synthesis and increased breakdown, culminating in blunted muscle fiber hypertrophy.”

The negative influence of cold water immersion didn’t show up across the board. There was no difference between the two groups in terms of strength gains, for example. Nor was growth in the slow-twitch muscle fibers affected by the cold.

What’s more, lean body mass in the legs – as measured by DEXA – was not significantly different between the two groups.

That’s probably because, according to the study authors, DEXA was “not sensitive enough to detect changes in whole-muscle size that may have been underpinned by the responses seen at the muscle fiber level.”

How Ice Baths Slow Muscle Growth

The “stress” of training leads to various signals being sent to your muscles. And it’s the nature and strength of those signals that dictate how well your muscles respond and adapt to the training.

The problem with ice baths is that they appear to decrease the strength of various “make me bigger” signals sent to your muscles in the hours after a workout.

Protein synthesis – a key driving force behind muscle growth – goes down, while protein breakdown is higher than it otherwise would be. The net effect is a slowdown in the rate at which muscle is gained.

In short, by working against your body’s natural response to tissue damage, you may end up slowing your progress rather than speeding it up.

Feeling sore, stiff and tired after training may well be a perfectly natural side effect of a recovery process that should be left well alone.

Cold Exposure and Recovery

None of this means that ice baths are useless. Used regularly as part of your training, the potential is there for them to put the brakes on muscle growth. However, they may well be useful for competitive athletes at times when rapid recovery takes priority.

Here’s what Dr Steve Ingham, who has worked with many Olympic medal winners, has to say on the subject in his excellent book How to Support a Champion:

“Jumping in a bath, wheelie bin or specialised inflatable dinghy type thingy is still in common practice and it is something I continue to recommend to top athletes. However, I only recommend it for in- or post-competition recovery, where quick turnaround of recovery is the priority.

“The body is smart. If you give it a stimulus to change, it needs time to let that stimulus resonate, but if you present another stimulus it can get confused. With the presentation of cold through ice baths you are interrupting and blunting the cascade of response and so there is every chance that the mechanisms of adaptation will simply shrug their shoulders and not bother to improve nearly as much.”

Journalist Mark McClusky makes a similar point in his New York Times bestseller Faster, Higher, Stronger:

“There is some sense in elite circles that during periods of training, it might be better to forgo using too many recovery protocols. A scientist at the English Institute of Sport, Jonathan Leeder, has written about the possibility that decreasing stress on the body through things like ice baths will necessarily decrease the beneficial adaptations from training. It might make the most sense for an athlete’s progress to save recovery exercises for competitive periods, when they’re focused on maintaining capabilities, not increasing them.”

There’s plenty of evidence to show that ice baths can make you feel less sore and fatigued [6]. What’s less clear is whether ice baths work simply because you expect them to. In other words, is the effect a physiological or a psychological one?

In his book Endure: Mind, Body and the Curiously Elastic Limits of Human Performance, science writer Alex Hutchinson reports on the findings of a 2014 study showing that a lukewarm tub of water containing a special “recovery oil” worked just as well as an ice bath for the recovery of strength in the days after a hard workout [7].

In fact, the special “recovery oil” was nothing more than liquid soap, added to a lukewarm bath as a placebo.

“We made sure that we put the recovery oil in the water in plain sight of the participants, and we gave them a glossy summary of some made-up research about scientifically proven benefits of ‘recovery oils,'” says Dr. David Bishop, a co-author of the study.

“I don’t think that we suspected that ‘recovery oils’ would be as effective as the cold-water immersion,” he admits. “That was surprising.”

So, what’s the bottom line?

Cold water immersion might be useful in cases where rapid recovery is required, although the jury is still out as to whether the underlying mechanisms are primarily physiological or psychological in nature.

However, if you want to make your muscles bigger and stronger, the evidence to date shows that ice baths may very well hurt your results if used on a regular basis as part of your training.