The image of an exhausted athlete leaving the field to submerge themselves in an ice bath is a popular trope in the media. Coaches and athletic trainers have used this method and similar approaches for years. But how effective are cold-water immersion protocols in improving performance? What does the science say about its efficacy?
The research on ice baths and other cold-water immersion protocols returns mixed results. However, multiple variables play into any equation. Timing, temperature, length of exposure, and frequency of exposure are only a few of the factors coaches must consider when determining whether to use this treatment. Furthermore, slight variations provide various applications for different uses.
What do athletic trainers need to know? Here’s an in-depth look at cold-water immersion protocols for modulating immune response and inflammation and how coaches can use the existing science to maximize performance on the playing field.
The Body’s Response to Exercise
What happens to the body during and immediately following exercise? Most people focus on the benefits. Training can increase an individual’s VO2 max, decrease heart rate and blood pressure, and build muscle mass. It also activates various substances and enzymes in multiple bodily systems.
For example, hormones like adrenaline and cortisol impact cardiovascular function. Exercise moderates their levels, spiking them during and immediately after intense exercise. They typically return to normal except in cases of overtraining, where the failure to decrease results in symptoms like increased irritability and inability to focus.
Adipose tissue releases adipokines and cytokines, which play crucial roles in inflammation and the body’s healing response to exercise. Muscles produce myokines, facilitating communication between the muscles and other organs and playing a role in recovery. Intestinal microbiota cranks up the fermentation of short-chain fatty acids in the gut to provide long-lasting energy to cells. Finally, the liver increases hepatokine production to regulate lipid metabolism.
Understanding how the body responds to exercise is crucial for coaches in determining the best protocols. It’s not the only factor they must consider, though. According to Dr. Robin Thorpe, senior performance scientist and conditioning coach for Manchester United Football Club, a coach must also look at the trade-off between adaptation and recovery. They must examine the underlying cause of fatigue—is it a temporarily inflamed knee thanks to repeated strain or metabolic fatigue extending across various energy systems?
Time is also a crucial consideration, including how long after exertion to use specific protocols and at what point in the season. For example, many trainers consider full ice bath immersion absurd in the pre-season. Inflammation plays a crucial role in inducing certain adaptations coaches want to encourage during this time, such as muscle growth and VO2 capacity.
Cold-water immersion immediately after exercise may feel great because of the temperature’s anesthetizing effects. However, it can suppress the release of IGF-1 and other healing substances carried to muscles by inflammatory cells—the same cytokines and adipokines accompanying swelling and redness. Healing slows down without a healthy supply, decreasing performance on the field.
Additionally, using ice during training may prevent the hypertrophic muscle changes desired through exercise. One recent study on the effect of ice baths immediately following a resistance training session found that exposure to cold-water immersion weakened the muscular adaptations typically seen as a result of such exercise.
Evidence also suggests that shifting the timing of the ice application provides a crucial difference. Share on XHowever, evidence also suggests that shifting the timing of the ice application provides a crucial difference. A cool—though not necessarily cold—bath 24 hours after exertion gives the nerve pathways used by these chemicals time to return to normal. It provides soothing refreshment but doesn’t interfere with the body’s natural healing work.
Techniques for Using Cold-Water Immersion in Athletics Programs
Ice and ice therapy has a role, even earlier in the season. While it will not cause muscle tissue to heal or grow more quickly, there’s more to athletic performance than the size of a linebacker’s biceps or the strength of their connective tissues. Exercise and on-field performance rely on the integrated coordination of multiple systems, including the central nervous system and that all-important component of it—the brain.
Coaches must know that inappropriately used ice therapy can hinder healing. The verdict remains out as to its overall effectiveness at reducing swelling. However, its power to relieve pain has been proven time and again. Pain is a huge determinant of on-field performance, as every survival instinct in the human body screams against “playing through it” for a good reason.
The body has various thermoreceptors and nociceptors, specialized nerve cells that detect temperature changes. These also influence muscle contraction and hair follicles—creating the signature “hair raising” effect occurring with goosebumps. Their job is to maintain homeostasis—in this case, a consistent temperature—by encouraging muscle contraction to raise interior heat and avoid cell death.
However, there are times when deadening the nerves and stopping the pain impulses allows performance to continue. For example, cryoanalgesia provides temporary nerve blockage to reduce pain along peripheral nerve pathways. It can serve a crucial role in treating chronic pain from scar tissue adhesions arising from previous, healed injuries that impact on-field performance.
Pain serves a critical purpose. It’s meant to tell humans to stop an activity to prevent further injury. However, using ice to ease pain in limited instances, like the above example, is an important tip for coaches to understand.
Cryoanalgesia is only one potentially useful application of cold-water immersion protocols in athletic training. Athletes must keep their heads in the game, and pain from overtraining can distract them and leave them with fatigue that’s as much mental as physical. The temporary psychological boost they receive from an ice bath creates a temporary illusion of healing that may give an athlete the right on-field mental edge to push past exhaustion and triumph over the competition.
Coaches must balance their athletes’ desire for a quick dip to regain their edge against the potential for injury. While this approach works to combat general fatigue, it shouldn’t encourage someone to play through a potentially dangerous condition.
Coaches must balance their athletes’ desire for a quick dip in an ice bath to regain their edge against the potential for injury. Share on XLikewise, coaches should keep such immersions short. Remember, exposure to cold causes muscular contraction, and tight muscles are more readily injured than warm, pliable ones. Prolonged cold-water immersion could leave an athlete unnaturally tense, leading to on-field disaster.
Coaches must also factor body fat, mass, and weight into the equation when approving cold-water immersion protocols. The core temperature drops more quickly in those with less fat and mass. For example, an American football lineman will resist a core temperature drop more than a soccer player. In contrast, sumo wrestlers have an edge on both of them for maintaining a consistent inner thermostat.
Francisco Tavares, PhD, suggests the following times and temperature variations for ice bath intensity, depending on the athlete’s size:
- Low: Eight minutes at 15° Celsius
- Moderate-low: 10 minutes at 15° Celsius
- Moderate-high: Eight minutes at 10° Celsius
- High: 10 minutes at 10° Celsius
Tavares advises using lower intensity for low-mass and low-bodyweight fighters. He cautions that larger athletes might need greater exposure, perhaps lengthening the immersion time, as they demonstrate lower core temperature changes after exposure.
Compare that to the typical immersion protocols some coaches use. Significantly shortening the length of the dip may be a wise choice.
Also, please note that the water temperature has a negligible effect on core body temperature. However, there’s a more significant difference in superficial and deep muscle temperature. Therefore, a brief dip of 10 minutes or less in a very cool tub of 0° C to 12° C could provide sufficient numbing, while longer dips do little good and may even increase injury risk by making muscles overly tight.
Mechanism and Effects of Cold-Water Immersion on Immune Response and Inflammation
Athletes often endure lasting inflammation affecting overused joints and tissues. Tennis elbow is one example of such an overuse injury. How effective are cold-water immersion protocols in reducing long-term inflammatory conditions arising from overuse? Can they address the systemic inflammation that occurs with chronic conditions affecting athletic performance?
Typically, heat is a more effective therapy for chronic injuries, as it encourages blood flow to the area to deliver the necessary nutrients for healing. For example, if an athlete has had previous knee surgery and chronic pain in the area, even moderate physical activity may aggravate it. However, applying ice to a chronically achy area immediately after exertion may lower the inflammation triggered by the body’s learned response.
When signals frequently stimulate the same receptors and travel the same neural pathways, these areas become sensitized to particular triggers. Therefore, the stimuli that might not prompt an inflammatory response in a previously uninjured individual can cause an exaggerated one in others. An athlete’s bum knee may always grumble a bit after practice, and ice may decrease this sensitivity.
It’s also important to understand how inflammation becomes chronic. It occurs in three waves. Acute inflammation happens immediately following an infection or injury. Chronic inflammation may last months or even years, with subacute inflammation serving as a transformational period of two to six weeks between the acute and chronic stages.
Here’s another area where athletic coaches may consider cold-water immersion protocols in hopes of preventing acute injuries that don’t require medical attention from becoming longer-lasting. Breaking the inflammatory chain may guard against chronic inflammatory conditions and keep minor issues from snowballing into lifelong problems.
Coaches should coordinate with physical therapists and the rest of an athlete’s treatment team and heed their advice. However, using cold-water immersion protocols to treat injuries after the acute phase has passed—but in the weeks before returning to the field—may keep a twisted ankle from burgeoning into a veritable Achilles heel.
Whole-Body Cryotherapy as an Alternative to Cold-Water Immersion Protocols
In recent years, whole-body cryotherapy has emerged as a competitor to cold-water immersion protocols such as ice baths. The practice has gained considerable popularity despite a relative dearth of scientific evidence supporting its use.
However, a recent study examined the dose-response effects of whole-body cryotherapy on elite rugby players. They found that two consecutive exposures immediately following fatiguing league competition stimulated an increase in their anabolic endocrine profile and reduced cytokine concentrations, a measure of inflammatory molecules in the blood. This made it possible to lower the body’s stress response and restore hormonal balance after extreme exertion.
Cryotherapy can get costly, with sessions ranging from $60 to several hundred dollars per session. Other cold-water immersion protocols, such as ice baths, are next to free.
Cryotherapy can get costly, with sessions ranging from $60 to several hundred dollars per session. Other cold-water immersion protocols, such as ice baths, are next to free. Share on XFurthermore, the mixed science means coaches must carefully weigh the potential risks against the benefits. If muscle-building in the preseason is the ultimate goal, avoiding cold-water immersion protocols is probably the best choice for most athletes. However, those needing a slight psychological edge, especially if their primary issue is fatigue from stress, may benefit from a dip. Such methods may help other bodily systems, such as the endocrine system, recover.
Using Cold-Water Immersion Protocols to Improve Athletic Performance
Cold-water immersion protocols such as ice baths have had a long history in athletic training. Coaches must understand how such methods affect the body so that they can use them to their greatest advantage. Although ice can inhibit muscle growth, it can calm the nervous system and the body’s inflammatory response and bring other bodily systems back into balance.
Knowing when and how to use cold-water immersion protocols helps coaches improve on-field performance. It also enhances athletes’ overall health, keeping them in the game.
Reference
White GE and Wells GD. “Cold-water immersion and other forms of cryotherapy: physiological changes potentially affecting recovery from high-intensity exercise.” Extreme Physiology & Medicine. 2013;2(26).
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