We all have different relationships with heat. Some of us live for 100-degree-plus sun-filled days; others not so much. But the addition of heat to workout classes, like yoga, Pilates, and even high-intensity interval training held in an infrared sauna, has found favor with a wide range of fitness seekers, adding a sweat-fueled element to already-grueling workouts.
But here’s the burning question (pun intended!): Does heat truly enhance exercise for women over 45 — or does a boiling workout session work against you? We asked Dr. Kimberly Higney, who focuses her practice on neuro-endocrine dysregulation and women’s hormone health, to break down the pros and cons of sweltering workouts.
In a nutshell: Hotter temps mean more sweat, and more sweat means your heart works harder — and, therefore, you work harder. Dr. Higney explains the process: In response to extreme heat in a studio environment, the blood vessels in your skin dilate to release sweat to maintain your body temperature close to 98.9. “This has the side effect of reducing your blood pressure, though, so to maintain blood flow, your heart rate must increase — which is all to say that your heart has to work harder in a heated studio,” she says.
While this can be seen as a positive, Dr. Higney notes that this type of intense workout can pose challenges in the long term, such as vitamin and electrolyte depletion.
Walk into a hot studio and the heat practically smacks you in the face. That’s because the typical temperature ranges from 90 to 105 degrees with 40 to 60 percent humidity. Dr. Higney likens this type of environment to running outside for 60 to 90 minutes in really hot weather. “Each of us responds to heat differently — how much we sweat, how hydrated we are, so even in a healthy person there is risk of dehydration and loss of electrolytes,” she says.
Here’s why this matters: A loss of certain electrolytes, like sodium, potassium, calcium, magnesium, and zinc, can cause muscle cramping, weakness, nausea, lightheadedness, fatigue, and mental confusion — and can even accelerate skin aging. If these electrolyte levels stay chronically low, Dr. Higney warns that you increase your risk of health issues like irregular heartbeat and, in rare, extreme situations, seizures and kidney failure. Intense heat also depletes water-soluble vitamins, like B and C, which are important for nerve function and repair and a healthy immune system.
While all of this sounds scary, you can avoid it. “Electrolytes should be replenished with every class,” Dr. Higney advises. “With attention to whole-food nutrition and to proper hydration before, during, and after exercise, much of this can be prevented. Some raw coconut water with a little salt is simple but can go a long way.”
If slimming down is one of your workout goals, hot exercise could benefit you. Dr. Higney points to the 2018 Bikram yoga heart study in which participants who practiced hot yoga three times weekly for 12 weeks lost more body fat (1 percent on average) than those who practiced the same routine under normal, unheated circumstances. It’s not a lot, but there was, at least, a measurable difference.
Hormones are where heated exercise can become particularly challenging for women over 45. According to Dr. Higney, the addition of heat during class can compound underlying hormone imbalances, such as low cortisol or low thyroid function (where B and C vitamin complexes and minerals are typically already depleted), as well as thyroid symptoms, such as fatigue, weight gain, and hair loss. Add to that, for women with low cortisol, heat can compromise progesterone production, which in turn worsens a condition of estrogen dominance. “This really depends on a woman’s underlying hormonal and nutritional status. Since so much of a women’s health and well-being is dependent upon her hormones, I recommend that women have their hormones tested at least annually to get ahead of any potential challenges and to understand which types of exercise will be most beneficial,” Dr. Higney says.
Certainly an already heated situation will only feel worse if a sweltering studio environment is added into the mix. “While not comfortable, hot flashes serve an important function (detoxification),” Dr. Higney explains. So while you shouldn’t try to suppress hot flashes altogether, adding hot yoga (or any other heated exercise) into your life could actually assuage the experience. “In an otherwise healthy woman the heat and increased circulation of hot yoga can … potentially lessen the intensity and length of time you experience hot flashes,” she says. And you won’t be the only woman in the room sweating!
Many women report less stress, more flexibility, and a greater sense of mental wellness and balance after practicing hot yoga — making them true devotees. But if you’ve experienced adverse affects from hot exercise, do you need to quit altogether? “This will depend on the specific health concern and how severe it is,” says Dr. Higney. “With sufficient hydration, whole-food nutrition, and rest, a healthy woman may practice two to three times a week and feel great, but once a week may be too much for a woman with low cortisol or, for example, multiple sclerosis. It may simply not be the right exercise for her at that time.”
Her advice: Listen to you body both during and after class. “If you need to slow down, sip more water, rest, or pause to come back to your breath, do it. If most days you’re Wonder Woman and feel unstoppable, but one day you feel lightheaded, pay attention; it just may be a little too much for you. If you’ve been practicing for some time and now regularly feel ‘off’ during class, consider possible underlying hormonal or nutritional imbalances,” Dr. Higney says. And if you need to take a step away from your favorite heated activity, don’t fret: With the fitness class boom alive and well, there’s something (including a purposely cold workout!) for everyone.