Contrast Therapy for Longevity - Hot and Cold for Health
Contrast therapy, also known as contrast hydrotherapy or contrast bathing, is the method of alternating between hot and cold exposure. This can be a combination of a warm bath and cold plunge or it can also be a combination of sauna (a heated room versus heated water) and cold plunge.
Contrast therapy is popular in the biohacker space, particularly with athletes who claim the benefits of a quicker recovery time.
However, despite recent popularity, combining sauna with ice baths goes back centuries.
The tradition of sauna, which comes from Finland, involved people alternating between sitting in a heated room and either taking a dip in an icy lake or rolling in the snow. These practices continue to be a part of Nordic culture today, embraced for health and socializing purposes.
In other cultures, the Russian banya is frequently combined with dips in frigid water during the winter, and in Japan, onsen (hot springs) are paired with cold plunge pools.
How Does It Work?
What exactly makes contrast bath therapy effective? The alternation between vasodilation and vasoconstriction is the primary physiological response that occurs from contrast therapy that makes it so beneficial.
When you immerse yourself in cold water, your blood vessels respond by shrinking (vasoconstriction). When you immerse yourself in warm water, your blood vessels open up (vasodilation).
Additionally, cold water speeds up your heart rate, whereas hot water slows it down.
These circulatory changes that happen from contrast therapy creates a pumping action throughout the body, which is crucial for circulatory and lymphatic (related to the immune system) health. Conversely, stagnation is generally not beneficial for your body, as it's the movement throughout your body that encourages organs and processes to work as optimally as possible.
This pumping action is thought to provide the benefits of contrast therapy outlined below.
How is Contrast Therapy Linked to Longevity?
It's evident that contrast therapy can support one's health, but how is it linked to longevity and the extension of one's life?
A few ways:
First, it's important to recognize that contrast therapy includes two distinct types of hydrotherapy that are both proven to be physically and mentally beneficial for people - cold water exposure and heat exposure. To recap, here are the separate benefits of both therapies:
- Lowered risk of cardiovascular disease
- Improved immune function
- Lowered risk of metabolic syndrome
- Improved mood and reduced depression
- Increases metabolism
- Improves cardiovascular health
- Improves cognitive function
- Increase release of growth hormones
- Lowers inflammation
- Increases FOXO3 (related to longevity)
Because cold water exposure and heat exposure both lower the risk of age-related diseases and improve health in these arenas as well, both are clearly linked to promoting longevity all on their own.
So is contrast therapy simply two longevity therapies smushed together?
Not exactly. As described above, not only are cold water exposure and heat exposure beneficial on their own, but the alternation between the two therapies creates a more enhanced/extreme pumping action throughout the body that supports circulatory and lymphatic health.
READ: 9 Best Sauna Options - Comparing Sauna, Steam Room, and Infrared
Benefits Of Contrast Therapy
So what exactly are the benefits of contrast bathing? Contrast hydrotherapy:
- Removes lactic acid. A study conducted in 2007 by a university in New Zealand showed that contrast therapy helps to flush out lactic acid, a chemical compound that builds up after strenuous workouts. In removing lactic acid, contrast therapy was shown to lessen the soreness and fatigue that occurs from vigorous exercise.
- Reduces swelling. In a study conducted in 2016, contrast therapy was shown to lessen swelling in 115 people with ankle strains, three days post-injury. Although the swelling after an injury is normal and necessary, as it's the body's way of starting the healing process, swelling can also cause more pain by putting pressure on the injury. By lessening the swelling, contrast therapy is thought to accelerate the body's healing process.
- Alleviates fatigue. A 2017 meta-analysis of research on contrast therapy showed that contrast baths improved the sample group of athletes' recovery and lessened fatigue for 24-48 hours post-game. Interestingly, to go back to the unique benefits contrast therapy provides over just one therapy or another, cold water immersion didn't demonstrate the same results.
- Lessens muscle soreness. A 2013 meta-analysis examined delayed onset muscle soreness (DOMS) and muscle weakness in athletes after strenuous workouts. Researchers found that contrast bath therapy alleviated soreness and weakness better than just resting. That said, the study showed that cold water immersion provided similar benefits to contrast therapy.
- Improves mood and manages stress levels. Contrast therapy lowers the stress in your body, releases endorphins that help to improve your mood, and calms the nervous system.
READ: 10 Best Cold Plunge Options for Longevity: Comparing Tub, Barrel, & Portable Inflatable Ice Baths
How Can I Get Started?
There are a number of ways you can get started with contrast therapy.
Depending on the ailment you're dealing with or the benefit you're looking to achieve, you can choose to do contrast therapy on your own, in a studio that provides this service, or with the help of a physical therapist or athletic trainer. As with any health protocol, your safest bet is to consult your physician to make sure there are no issues with you experimenting with contrast therapy.
If you're rehabbing an injury, a physical therapist may have you do contrast therapy involving whole body immersion or only immersing the injured body part. They'll have different tubs or whirlpools that you can alternate between as they prescribe.
You can find a studio near you that offers contrast therapy. The set up will be similar in the sense that they will have multiple tubs of water at varying temperature. Similar to a rehabilitation or physical therapy clinic, the staff will be able to walk you through the recommended protocol for best results.
If you decide to try contrast therapy on your own, you'll need two tubs, a thermometer to gauge the temperature of water in both tubs, a way to cool and heat the water to the desired temperature (e.g. ice for cold water), and towels.
Different sources recommend different protocols for contrast therapy, but here are some guidelines and suggested protocols.
Contrast Therapy Guidelines
Water temperature: Cold water should be between 50-59°F (10-15°C), and water in the hot container should be between 95-113°F (35-45°C). A study showed that the most effective temperature range for hot water was less than 104.
Start with hot water first: Although this is up for debate, most sources claim that starting with hot water is the way to go. In fact, getting hot water immediately after an ice bath can be unsafe.
End with cold water: If you’re dealing with inflammation or swelling of any kind, ending your contrast therapy session with cold will keep the inflammation and swelling down to a minimum.
Session length and frequency: Sessions will last generally anywhere from 20-40 minutes depending on the protocol you decide to go with, and it's recommended to do contrast therapy anywhere from 2-4 times a week depending on your comfort level.
Contrast Therapy Directions and Protocols
To get started with contrast therapy on your own, follow these steps:
- Immerse your body or the injured body part in warm water for a given period of time (protocol options outlined below).
- Immediately follow with cold water immersion. The best way to approach this is to fully submerge yourself once you get in.
- Repeat this process for either a given period of time or number of times.
There are many different protocols out there, but here are a few to give you an idea of what could work for you:
- Warm water for 1-3 minutes, 1 minute in cold, repeat for 20 minutes.
- Warm water for 20 minutes, cold water for 3-10 minutes.
- Warm water (or sauna) for 15 minutes, 1-5 minutes ice bath. Repeat twice.
Remember, if you're just getting started and the cold water temperature is hard to bear, start off small and work incrementally until your body gets more adapted to the extreme temperatures.
What Are the Risks of Contrast Therapy?
Although minimal, the risks of contrast therapy are the possibility of damaging your skin and any issues that might occur if you have a pre-existing heart issue (due to the alternation between vasodilation and vasoconstriction and also the variability in heart rate).
These physiological changes can cause heart arrhythmia, so it's important to discuss contrast therapy with your doctor before getting started or avoid it completely if you have any of these conditions:
- Pregnancy
- Open wounds
- Heart issues
- Cardiac disease
- High blood pressure
- Deep vein thrombosis
- Abnormal skin sensations
- Hypersensitivity to cold
- Impaired circulation
Contrast Therapy for Longevity
If you haven't incorporated sauna (or any type of heat exposure) or cold water exposure, these modalities have countless benefits that support your longevity.
Utilized together via contrast therapy, where you alternate between hot and cold hydrotherapy a number of times, has been proven to not only provide the existing benefits of each therapy separately, but can help more with muscle fatigue, swelling, soreness, and lactic acid buildup after a workout. Additionally, the pumping action that's created within the body due to the alternation between hot and cold can provide more benefits to the circulatory and lymphatic system, all of which promote health and a longer lifespan.
Upon consulting with your doctor and assessing yourself for any of the conditions listed above, consider incorporating contrast therapy in your longevity toolkit to take the benefits of hot and cold water exposure to the next level.
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