They're bad for your hair but good for endurance.
In Cost-benefit analysis, experts explain whether the pros of widely adopted health trends outweigh the cons—or vice versa.
The ritual: hot showers
The costs:
Hot water strips your hair and skin of the natural oils that protect you from the elements (weather, products, etc.), says Ashley Hudson, senior regional manager of EQX Body Lab in New York City.
On top of that, it loosens hair at the follicle level and removes keratin, a naturally occurring protein that helps smooth strands. These effects can make your hair thin and coarse.
Extremely hot showers (think: scalding, steaming) can break the capillaries just beneath the skin, especially if you're prone to the issue. These red, vein-like marks never go away, Hudson says, and the damage increases your risk of dehydration. (FYI: Dryness is lack of oil and dehydration is lack of water. The former can make you more susceptible to the latter, says Hudson.) The delicate skin on your face, like that on your nose and around your eyes, is most susceptible.
Turning up the heat even affects your fitness. Recent research found that muscle growth was stunted in people who consistently took hot showers after strength workouts for 10 weeks in a row. One potential explanation is that scalding water reduces inflammation too much, explains Micah Zuhl, Ph.D., associate professor in the School of Health Sciences at Central Michigan University in Mount Pleasant. “Some level of inflammation is necessary for the muscle to adapt to exercise."
The benefits:
Heat acclimation is one of the most notable.
Research indicates that athletes perform better in high temperatures after bathing in hot water for six days in a row. The resulting acclimation also sparks an increase in blood plasma, a benefit that can last up to two weeks. From an endurance perspective, that’s advantageous because the more plasma you have, the more oxygen and blood get delivered to the muscles, Zuhl explains. Showers likely have the same benefits.
When taken pre-workout, hot showers can reduce post-workout soreness, he adds. Studies also show they can help your body transition into prime sleep mode.
The final analysis:
If you're training for a race in a hot climate, take steamy showers or baths for at least six days leading up to the event (for up to 30 minutes at a time). Zuhl notes the water should be at least 104 degrees Fahrenheit, about the temperature of a hot tub. For sleep benefits, take one in the two hours before bedtime.
In all other cases, your showers should be lukewarm—think cooler than your body temp.
If your skin feels swollen or squeaky afterwards (a sign that the oils have been stripped) or if it looks pink or red, you went too hot, Hudson says. Apply a hyaluronic acid face mask and use shea butter or coconut oil body lotion to rehydrate the skin.