You’ve likely heard of runners taking an ice bath as part of their training, but you might not be sure if it’s for you. If that’s the case, read on for a breakdown of cold therapy for runners, the science behind cold-water immersion, and how to best incorporate it into your training.
What’s an Ice Bath for Runners?
An ice bath is exactly what it sounds like: a post-run plunge into a tub of icy cold water (often filled with actual ice). It may sound painful, but runners use ice baths in the hopes of faster recovery and reduced muscle soreness after an intense training session or a race.
An ice bath is a form of cold-water immersion, which is a type of cryotherapy (cold therapy). There are other forms of cryotherapy, and they range from applying an ice pack to an acute injury to standing in a full-body chamber that’s been cooled with liquid nitrogen, but an ice bath is the most common cryotherapy technique used to manage muscle soreness following exercise.
Cold-Water Immersion for Runners: The Science
The overall theory behind cold therapy for runners is that it constricts blood vessels and decreases metabolic activity, which in turn reduces swelling and tissue breakdown and shifts lactic acid from the muscles.
When your body is exposed to the cold, it responds by constricting your blood vessels (a process called vasoconstriction), so all your blood gets pushed toward your organs, allowing the blood to acquire more oxygen. Then, once you start heating up again, your blood vessels expand (vasodilation). Oxygen-rich blood flows back into your tissues and flushes out inflammation.
Less blood flow while soaking in cold water means less inflammation means less pain and soreness, ultimately leading to faster recovery. “This may help to reduce the amount of fluid being released from the blood into the surrounding tissues following an injury, thereby reducing the amount of tissue swelling." So, taking an ice bath after your next run sounds like a no-brainer, right?
Not so fast.
While there are benefits of cold-water immersion, if you’re trying to build muscle and conditioning, an ice bath may not be your best bet.
Even though decreasing tissue breakdown sounds like an admirable goal, microtears in our muscle tissue are actually the key to building muscle mass.
Studies have found that reducing blood flow slows muscle protein synthesis—meaning that using any form of cold therapy can make it more difficult to repair or build muscle.
When Should Runners Take an Ice Bath—And When To Not
Understanding the pros and cons of ice baths is key to knowing when to use them.
If you’re fighting an injury, ice baths can be a great tool to reduce the pain and swelling that comes with sprains, strains, and fractures.
And if you’re looking to prevent the dreaded DOMS, some cold-water immersion is a good way to proactively manage pain and recover faster. This can come in handy if you don’t want to be slowed down by soreness in your day-to-day life. This can be particularly useful when you’re racing on back-to-back days.
But does it make sense to turn to cold therapy after a particularly long or intense run? Not if you want to reap the benefits of your hard work. As annoying as it is to have to hobble down your stairs the day after your hard run, that post-workout inflammation you’re feeling is necessary for adaptation.
You know the old adage: No pain, no gain. If you’re trying to set a new PR or generally improve your running performance, it might be smartest to stay out of the ice.
How To Make an At-Home Ice Bath
Now that you understand the potential benefits and drawbacks of post-exercise cooling, you might be interested in trying it yourself. The good news is you don’t need access to a professional training room or the address of the nearest cryo chamber to get the benefits of cold therapy.
To make an ice bath at home, fill a tub with the coldest water you can. Throw in a five-pound bag of ice for the full effect.
You can measure the temperature before getting in (54–59F is recommended by most athletic trainers), or, if it feels cold enough, go ahead and get in. It shouldn’t feel unbearable, but it should be uncomfortable enough to trigger your body’s stress response, which is key to unlocking the benefits of cold therapy.
If you’re new to cold-water immersion, start off with less exposure time and gradually work your way up to 10 minutes in the ice bath. Don’t linger long beyond that—at 15–20 minutes, you’ll start putting yourself at risk of hypothermia.
After you get out of the bath, warm up with a hot beverage. An ice bath can be a great excuse to drink hot cocoa, whatever the outside temperature may be.
Ice Baths for Runners: Our Final Thoughts
If you’re still not sure if ice baths have a place in your post-run recovery plan, it doesn’t hurt to try one every now and then to boost your recovery. But if you regularly find yourself using them to recover, you might be training too hard and losing any fitness gains.
And if you’re just not interested in taking the plunge, don’t sweat it—you’re probably not missing out.