What is it:
Cold therapy (Cryotherapy) is a recovery method often used by athletes and active individuals attempting to enhance recovery and reduce exercise-induced soreness. Cold therapy can be delivered locally via ice packs, ice massage, or cooling sprays or applied to the entire body using a chamber with extremely cold air (-200 to -300F) or sitting in a cold water tank or bathtub filled with ice (50-60F).
Although cold therapy is widely used in sports medicine around the world and the R.I.C.E protocol (Rest, Ice, Compression, and Elevation) has been taught as the gold standard for acute musculoskeletal injury treatment for decades, scientific research investigating different types of cold therapy has not always produced positive results, and for some common scenarios observed in sport relevant research is not available. The following summary focuses on scientific research investigating cold therapy's possible benefits and disadvantages for sports performance and recovery.
Purported claims:
Reduces inflammation
Reduces feelings of pain and fatigue
Lowers tissue temperature
Removes waste products
Improves recovery
Blunts natural healing response
Attenuates strength gains and protein synthesis after resistance training
What the science says:
There are two primary competing theories regarding icing and cold therapy. The first claims that cold can reduce pain and soreness by decreasing inflammation, enhancing recovery, and enabling people to return to exercise faster. The other theory suggests ice baths might stunt the body's ability to adapt to whatever training has just occurred or delay the healing in the case of an injury. Interestingly, one of the original proponents of the RICE protocol, Dr. Gabe Mirkin, has since cautioned the use of ice for anything but acute injuries based on recent findings that ice can compromise some aspects of the healing process.
A study with 11 runners showed that whole-body cryotherapy (WBC) effectively reduced the inflammatory process by reducing several inflammatory markers versus passive recovery. However, a study comparing cold water immersion (CWI) against active recovery (such as easy cycling) on inflammatory cells after intense resistance training found no difference in inflammatory markers between the two groups.
A couple of studies focused on strength training subjects who used either CWI or active recovery after every training session for several weeks found that cooling seemed to attenuate training adaptations such as muscle growth and blood supply to the muscles. A potential mechanism responsible for this observation may be that the body's temperature needs to be elevated during and after training to support critical physiological healing processes. Cooling the body could hinder some processes that lead to exercise adaptations.
Delayed-onset muscle soreness (DOMS) is the most common after-effect of strenuous exercise. Most people use ice baths and other recovery methods to ease the pain. When it comes to soreness, a meta-analysis examining the effects of CWI on recovery from strenuous exercise reported that CWI is an effective strategy to reduce muscle soreness and swelling and enhance recovery at least for the first 96 hours. Cold Water Therapy has often been found to help athletes cope with the pain and discomfort associated with excessive training loads.
A study among cyclists found that active recovery produced lower blood lactate concentrations than cold therapy when it comes to thermal stress due to intense exercise. Still, CWI was more effective in reducing thermal stress and more effective in subsequent high-intensity cycling performance. The lowering of tissue temperature has been found to decrease nerve conduction and, therefore, the perception of pain and a reduction in muscle spasms. Another study among elite cyclists stated that CWI might be beneficial for acute recovery during a hard training blog or a multi-day event but could impair long-term performance by decreasing the adaptations from training.
Intense exercise builds up carbon dioxide in the body, which causes your blood pH to decrease, causing acidosis. Muscle acidosis contributes to the development of peripheral fatigue and impairment of a muscle's force-generating capacity. Some studies have shown CWI to lower acidosis, enhance metabolite clearance, and reduce metabolic waste accumulation.
One of the adverse effects of intense exercise is nervous system fatigue, which can lead to decreased performance, especially when there is inadequate recovery time between consecutive days of hard training or competition. A study among soccer players showed that CWI improved central and peripheral fatigue recovery leading to earlier recovery and readiness to play.
Our take:
Many athletes swear by cold therapy because it makes them feel better. If you’re one of these people, it’s acceptable to keep doing it for occasional pain relief and to enhance recovery. Perception of pain and lack thereof are powerful psychological forces and shouldn’t be ignored.
On the other hand, dunking yourself into a bathtub filled with ice after every workout will probably rob you of some of the very adaptations you’re trying to gain from the training. So be smart about when to ice: Acute injury for the first few hours after or between back-to-back hard training sessions or tournament play is okay. Making it a daily habit, probably not.
It’s always good to remember that the tried-and-true recovery methods such as a proper cool down, stretching, massage, healthy nutrition, and adequate sleep will go a long way toward reducing fatigue and soreness while ensuring you get all the benefits of the training.
Will this benefit you?
The best application for cold therapy is to hasten recovery when you have limited time, such as between tournament play, where pain and fatigue could hinder subsequent performance.
Still curious to try it? If you do, here is what to keep an eye on:
Frostbite and cold-induced rashes are some of the possible injuries caused by cold exposure. Cold therapy causes vasoconstriction, which means the blood vessels closer to the skin surface narrow and constrict, directing the blood towards vital internal organs. If the cold and low blood circulation is held too long, the skin tissue can freeze and permanently damage. The restricted blood flow can also damage nerves and cause nerve pain.
People with poor circulation in their hands and feet (Raynaud’s disease) should be cautious about using cold therapy as it can trigger the syndrome. The same goes for people with high blood pressure and known heart disease, as cold immersion produces an acute rise in blood pressure and heart rate and can cause severe cardiac stress.
References and additional reading:
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