The most painful part of a workout often comes after the exercise itself. The day after a hard run or an intense lifting session, almost everyone feels the pain associated with sore muscles. Researchers call this phenomenon DOMS, or delayed onset muscle soreness, and it’s the reason many of us turn to various techniques we’ve been told relieve the pain and speed up the recovery process.
Tactics from foam rollers to compression tights to ice baths have become popular among all athletes, whether they be weekend warriors or elite competitors. But none of them are the miracle products we often think they are.
Why do our muscles get sore after we exercise?
The reason we get soreness in the first place has to do with what’s happening inside our muscles when we workout: We generate small amounts of damage to the muscle fibers themselves. As frustrating and painful as it might be, this soreness is normal and part of the muscle building process. Doctors, physical therapists, and even athletes themselves can test for this by measuring something called force production, which is the number of times you can perform a certain activity or lift. Comparing the force production during a workout versus 24 to 48 hours afterwards gives a glimpse to the amount of muscle damage. The lower the post-workout force production is compared to the original, the more the muscles are damaged.
All this muscle damage also causes some pain, but the two are not linearly related, says Nicole Dabbs, a kinesiologist at California State University, San Bernardino. The level of pain a person is in after a workout doesn’t always directly correlate with the amount of damage. That’s because pain is a perceived measure of muscle damage and it is highly subjective; the same level of muscle damage in two people could cause a significant amount of pain in one person and far less in another.
But it’s the pain, not the actual muscle damage that typically drives people to use these muscle recovery tools. In fact, Dabbs says, there probably wouldn’t be this plethora of recovery mechanisms and tools if the pain factor didn’t exist. Still, she notes, “pain matters.” Regardless of how damaged their muscle fibers are, people who are in pain aren’t going to be particularly inclined to exercise as intensely until the pain goes away.
There are plenty of happy customers for all of these recovery tools, and more tools seem to but studies on whether these products actually work are far less common.
“A lot of times we want this cookie cutter thing where we can say foam rollers work for everyone but I think it’s hard to people, including researchers, to grasp that there isn’t one thing that works for everyone,” says Dabbs. What may work for one person she says, may not work for another due to factors like training status, percentage of fast- versus slow-twitch muscle, biological sex, type of training, age, and others. Plus consumers typically judge a product based on their level of pain afterwards, not on scientific evidence of muscle recovery.
So here’s what the science has to say about whether these recovery tools actually work.
Ice bath
Women’s marathon world record holder, Paula Radcliffe, took a 10-minute ice bath following her record setting win at the London Marathon in 2003. After she mentioned the polar plunge to the news media, the popular recovery ritual became even more widely used. Athletes around the world and in every sport swear by this method.
But does it work?
Because of its popularity and perhaps simplicity (any large bucket of water and ice or even a cold stream or river will do), ice baths are among the most studied muscle recovery methods. The idea is that the prolonged, super-cold temperatures reduce the swelling and pain that comes along with muscle damage. (Most of the time, the swelling is so slight that it’s mostly unnoticeable for an every day exerciser.) However, Dabbs points out, and several recent studies suggest, that that reduction in swelling might also hinder the recovery process since swelling is essential for muscles to recover and regain their strength.
As to whether it works to reduce pain, some studies show it does and some that it doesn’t. On the whole, ice baths do seem to provide a reduction in associated pain, but the amount it does so might not be any better than the placebo effect.
In one study, researchers had a group of “recreationally active” men cycle for a short period, then had them undergo one of three recovery conditions: An ice bath, a warm bath (as a control), and a bath with a common skin cleanser that participants were told was a newly developed “recovery oil”. This last group also got a pamphlet explaining the purported evidence supporting this oil to further entice them to believe it would work.
Prior to beginning the treatment, when asked, participants in the ice bath group and the “recovery oil” placebo group both believed, to a similar degree, in the integrity of the recovery methods they were about to receive. If they didn’t actually believe in the treatment to begin with, this could influence how they felt about it in the end. After the treatment, both the ice bath and placebo groups reported a similar positive degree of recovery, which was more than the group that received the warm bath, the control. For reference, the warm bath and the placebo were exactly the same, aside from a bit of skin cleanser.
Dabbs says there many still be some benefit to a post-workout ice bath during specific training phases. It could be okay to use if it really does give you pain relief and you don’t need your muscles to recover quickly, for instance, if you had a race or hard training session in the next couple of days. However, it’s probably not a good idea to take an ice bath too close to an upcoming intense training workout or a competition. For that the research is more clear: Reduced muscle temperatures impact performance and warmer muscles always perform better (which is why we warm up in the first place).
If that’s the case and you can handle the cold, do it just for the placebo effect. After running a marathon or following a championship game would be a great time to test out the cold.
Whole Body Cryotherapy
Whole Body Cryotherapy, in which a person enters a chamber with sub-zero temperatures for no more than a few minutes, is essentially a high tech ice bath. The main difference is in the transfer of cold to your body. Water is able to store more heat for longer periods than air, which means it’s better able to cool you down. A study done that compares the two treatments—a traditional ice bath to whole body cryotherapy—found that a chilly soak reduces blood flow and tissue temperature better than the cryotherapy.
What effect that has on your muscles is a different question, and subject to all the same conflicting results as a standard ice bath. Another, more recent study, published in 2019 in the European Journal of Applied Physiology, found that whole body cryotherapy was more effective than cold water immersion (an ice bath) at participants’ perception of pain and other responses after resistance training, though the study notes that “neither [intervention] was more effective than the placebo treatment at accelerating recovery.” At-home polar plunges do come at a far cheaper cost, though; depending on the area, entering a cryotherapy chamber could cost you about $75 a pop.
Foam Rollers
Foam rollers are a permanent fixture in many athletes’ training regimens. It’s meant to work by inducing self-myofascial release, which is when the layer of tissue that sits on the outside of a muscle loosens up. In some cases, muscle soreness can be brought on by tightened fascia, and pressing on it is meant to relax that grip. This is thought to improve range of motion around a joint and reduce DOMS.
Unfortunately, whether or not this actually improves athletic performance or muscle recovery isn’t clear. The majority of the research done on foam rollers doesn’t show any positive benefits on performance during the recovery process, says Dabbs.
Newer foam rollers have vibrating components, which are meant to combine the pressure and benefit of a massage with the help of vibration technology. One recent study, published in January 2019 in the Journal of Sport Rehabilitation, found that the vibrating foam rollers increased participants’ pain tolerance. Others, though have found no difference between vibrating and non-vibrating foam rollers. However, vibrating foam rollers have only come out in the past couple of years and there just might not be enough vigorous studies done yet, to know for sure.
Compression Tights
Compression gear for athletes is a multi-billion dollar industry, and wearing them has become almost a status symbol: If you need them, you must be doing some extreme workouts. But like other recovery methods, the research seesaws over whether it does anything to help muscles recover.
Compression tights have traditionally been used for medical purposes to help people with circulatory conditions. When worn, they create a pressure gradient by having the level of compression decrease from the distal (or furthest away from the body) part of a person’s leg or arm to the proximal (inner part). This increases blood flow through the veins and reduces swelling. Studies show they works for both people with circulation issues as well as healthy subjects.
For athletes, the idea is that the increased blood flow also increases the clearance of blood lactate and creatine kinase, both of which get released from muscles and into the bloodstream after vigorous exercise and is a signal of muscle damage.
However, the data to back up these claims is weak. At best, some studies show it to be as effective as other mechanisms we’ve discussed here—that is, minimal—and at worst, research shows them providing no benefit at all. One particular problem, as noted in a 2010 review article by Australian physiologist Shona Halson, is that many of the studies done don’t measure the compressive forces of the garments so it’s impossible to be sure they are increasing blood flow appropriately.
A recent 2020 review published in the Open Access Journal of Sports Medicine looked at 21 studies that examined the the effects of compression tights, found that wearing them did improve performance in a small number of studies, and the researchers concluded that compression socks could help with perceived muscle soreness during recovery. Though, the mechanism behind that isn’t established. And the study concludes that research is still needed to establish that as well as the longterm effects of compression tights on athletic performance.
You might be better off trying other recovery methods, but if you do choose to wear compression clothing, the best time to do so is after exercise, not during. A few studies also suggest that the longer you wear them, the better. And opt for full length tights or ones that cover the lower legs, as opposed to shorts.
Stretching
If you remember back to PE class, you might recall sitting in a circle and stretching one area of the body at a time. But at least for the past decade, researchers have found convincing evidence that this practice, called static stretching, isn’t really that helpful in warming up your muscles. What’s far better is something called dynamic stretching, which involves moving and engaging more than one muscle group at a time.
Dynamic stretching increases blood flow and warms up muscles, which is crucial to athletic performance, whereas static stretching really doesn’t. But that’s not to say that static stretching isn’t important. According to Dabbs, they help to increase range of motion at the joints that connect muscles together. These stretches are critical in performing a range of everyday and athletic movements such as weight lifting, running, and daily activities.
So, stretching is still important, but remember: Dynamic stretching before and static stretching after.
Massage
Like other recovery methods, there’s a lot of mixed evidence over massages, which work to reduce the tension of the muscle’s fascia. On the whole, they probably do help. But the main problem, Dabbs says, is whether people can realistically use it on a regular basis as a recovery mechanism. Massages are usually done by professionals, namely physical therapists, who know how to perform them properly. “Even if it is beneficial, most individuals don’t have the money or time for massage.” However, she says, “there are some clinical benefits of massage in a rehabilitation setting.”
Pain Relieving Drugs
There’s much more hard evidence on drugs than other recovery techniques, but it’s not a positive: These should be a last resort. While medications like non-steroidal anti-inflammatory drugs like aspirin and ibuprofen work well at minimizing pain, they come at a cost. Many recent studies show that they greatly inhibit the naturally recovery process of muscles. Some of this research suggests that NSAIDS inhibit the proliferation of a group of muscle stem cells known as satellite cells, which play a key role in muscle repair. So if you can handle the pain, Dabbs says, it’s probably best to just tough it out. Though, of course, there’s a place for them: “If there is an intolerable amount of pain (since you still need to be mobile)” the benefits likely outweigh the costs, “but knowing it may hinder the recovery process.”
The one technique most people forget about: Sleep
Most Americans, athletes, and everyday exercisers included just don’t get enough of it. Average adult humans need about eight hours. Endurance and full time professional athletes probably need closer to nine or ten. In recent years, there’s been a hike in research on the effects of sleep and muscle recovery and subsequent athletic performance. And while scientists haven’t pieced apart the exact mechanisms through which muscle recovery and proper zz interact, they do know that sleep plays a crucial role in nearly every organ system in the body. And if you are going through all the trouble and spending the money on these other recovery mechanisms you should at least make sure that you are getting a good night’s rest, too.