Studies Show How Sweating Can Be Good for Your Health

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We all know exercise is good for your overall health. But what about the act of sweating itself? Does purposeful exposure to heat have health benefits? Studies show that exercise in heat stresses the body, but heat exposure can promote beneficial adaptations in fitness when managed strategically .

Extreme heat poses health risks, so approach heat training with care. In general, long, difficult race efforts at high temperatures should be avoided, as we see in cases such as the New York City Triathlon, which canceled its July 2019 event due to extreme temperatures. Exercise in the heat puts stress on the body that can cause heat-related illness like heat cramps, heat exhaustion and heat stroke if your core temperature gets too high.

Both exercise and passive heat exposure can cause the core body temperature to rise. The body responds with a higher heart rate to pump more blood through the skin and begin perspiration. If the air is humid, sweat cannot cool the body as effectively, causing more bodily stress. Bodily stress, however, isn’t always a bad thing. When treated as intentional training-related stress, heat exposure can bring impressive gains in fitness, so long as it’s monitored and balanced with proper recovery.

[Editor’s note: Running or exercising in the heat can be dangerous. Always consult a physician before beginning any new training plan.]

Here we explore how breaking a sweat is good for your health.

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1. Sweating may improve VO2 Max, blood plasma volume, and adaptability to temperature changes

In 2010, Santiago Lorenzo conducted a heat training study with 20 athletes. After only ten days of heat acclimation, they showed remarkable gains in VO2 Max, increased blood plasma volume and the body’s ability to cool itself.

Following the study, Lorenzo told Outside Magazine heat training provides more substantial environmental improvements in aerobic fitness than altitude acclimation. Lorenzo concluded the body adjusts to temperature changes faster than it does to differences in altitude. In this particular study, cyclists improved their time trial results by 6 percent in cool conditions and 8 percent in hot conditions.

This is good news for runners who don’t live at altitude or have easy access to altitude training. Temporary exposure to heat is generally easier to access, whether it’s by exercising outdoors or relaxing in a sauna, hot tub or bath.

2. Sweating may reduce the risk of high blood pressure

Sweating it out via regular exercise reduces the risk of high blood pressure by making the heart stronger, pumping blood with less effort and reducing the force on arteries. In addition, studies have shown passive sweating in a sauna also reduces the risk of hypertension.

A 2018 study on 100 men and women showed reductions in systolic and diastolic blood pressure following 30-minute sessions of sauna bathing. Another study (2017) followed participants for 24.7 years and found that those who used a sauna regularly (4-7 times per week) had a 47% reduced risk for developing hypertension.

It’s important to note all of these studies were completed in controlled conditions. If you have high blood pressure, this doesn’t mean you should start exercising in high heat every day. On the contrary, when starting a new exercise program, ease into it slowly and give your body a chance to slowly adapt.

3. Sweating may improve lung function

Just as exercise improves heart health, it may also be good for your lungs. Gains in physical fitness increase your body’s efficiency at processing oxygen and transporting it to your muscles.

In addition, passive sweating in the sauna can bring additional health benefits, according to a 2017 study published in the European Journal of Epidemiology. The study on twelve male patients with obstructive pulmonary disease showed transient improvement in general lung function.

An earlier study (1989) showed improved lung function including vital capacity, volume, ventilation and forced expiratory volume. Others even showed a reduced incidence of the common cold among regular sauna users vs. those who did not use a sauna.

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4. Sweating may reduce the risk of Alzheimer’s disease and dementia

Both exercise and passive sweating (periodic sauna use) may reduce the risk of Alzheimer's disease and dementia.

A 2016 study showed an association between sauna use and reduced risk of Alzheimer's disease and dementia among Finnish men. While the cause of these diseases is not widely understood, other studies have shown that moderate exercise such as regular walking increases the size of brain areas linked to planning and memory, which generally delays the progress of cognitive decline.

Experiments in varying age groups show that the hippocampus, the part of the brain associated with memory and learning, responds well to aerobic exercise and grows as fitness increases.

5. Sweating can protect your body from bacteria

Our bodies have many defense mechanisms to protect against bacteria and disease. This is an area where sweat shines. Sweat contains a concentration of antimicrobial peptides called dermcidin that protects your skin from external bacteria. As one of the first lines of defense for your body, some researchers say it’s more effective than traditional antibiotics because germs can’t quickly develop resistance to it.

This is not the same, however, as “detoxifying” the body through sweat. Intense sweat sessions tend to be falsely glorified as ways to remove toxins from your body when the credit for that job is actually owed to the liver and kidneys. While small quantities of toxic substances may be detected in sweat, the act of sweating is not an efficient way for the body to rid itself from harmful substances.

Before you intentionally seek out the heat, consider:

All the studies focused on heat training and fitness gains were conducted in a controlled and closely monitored environment. If you choose to incorporate heat therapy into your training, first consult a physician to determine if it’s safe for you, then start slowly, be strategic, and keep certain factors within your control.

  • Extensive sweating can lead to dangerous states of dehydration. Always start your workout hydrated and continue to hydrate, and replace electrolytes after you work out.
  • Limit the amount of time in the heat.
  • Just like you wouldn’t run a speed workout every day, running in extreme or excessive heat is not recommended every day.
  • Running in the heat is always more difficult for your body than in cooler temperatures. If you have an extremely taxing or difficult workout, it is generally better to complete it in the cooler part of the day, then do a short, easy run in the warmer hours if you want to add that strategic heat stress.
  • Use heat training carefully. A run in the heat is equivalent to a hard day. Be strategic about when to use these days and always let your body rest in between.

By Kate Schwartz. Schwartz has been running competitively for 20 years, and she currently runs with the Asheville Running Collective. She lives in Asheville, North Carolina, with her husband, Alex, and their cat, Clementine.

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