When you're subjecting yourself to something the creator, Bikram Choudhury, has called "the torture chamber," you want to know you're going to get results. Hot yoga, or Bikram, performed in a 105-degree F room with 40 percent humidity taxes your muscles, flexibility and mind.
The sequence of 26 postures never wavers — every class is the same. However, with this systematically designed routine, you're promised to reach your proper weight, ideal muscle tone and a glowing sense of well-being.
How long it takes to achieve these gains depends on your starting point, your expectations and your commitment. While the physical act of the yoga practice will benefit you, especially if you're coming from a sedentary lifestyle, it may not be everything you need to achieve your goals.
A lot of people come to hot yoga for the spirituality, and a lot of others come to lose weight. The typical Bikram class lasts 90 minutes, and burns approximately 460 calories per session for men and 330 for women, according to a Colorado State University study published in 2014.
Calorie burn helps you lose weight — when you burn more calories than you consume, fat loss happens. While Bikram does help boost your activity level, it might not be enough to see fast results. A pound of fat equals 3,500 calories, so you'll need to burn that much off — equal to eight to 10 classes — to make the scale drop by 1 pound. You can speed things along by tweaking your diet to contain fewer calories and mostly whole, unprocessed foods. In general, though, you might experience only a modest change in weight after several months of a thrice-weekly Bikram class.
Total Body Strength and Flexibility
The Colorado State University researchers also tested whole-body strength in people who underwent an eight-week, 24-session Bikram program after never having participated in it before. The new yogis did experience significant gains in their spine, shoulder and hamstring flexibility. They also had improved whole body strength.
If you're looking to leave Bikram looking like a bodybuilder or figure competitor, though, you'll be disappointed. The improvements are enough to give you some improvements in muscle mass, but may not make you look lean and muscle-bound.
If you're looking to boost your heart and lung health, you might have to seek another activity in addition to Bikram. The CSU researchers noted very little change in aerobic fitness following the eight weeks of Bikram.
Another study, sponsored by the American Council on Exercise and published in 2013, found that your maximal heart rate in a hot, or Bikram class, reached about 57 percent of max. This is only high enough to be considered light intensity and not enough to make marked changes in your overall fitness — no matter how many weeks you commit.
How you feel after taking Bikram yoga is hard to measure. If it improves your state of mind, reduces stress and enhances your mood, then it works. How many classes you need to undergo to experience these effects is subjective and almost impossible to quantify.
But, for some populations, Bikram can improve specific health markers associated with well-being. For example, a small study published in the Journal of Bodywork and Movement Therapies in 2013 found that eight weeks of three Bikram classes per week improved glucose tolerance in older, obese people, but not young, lean participants.
The scant research that's been performed on Bikram suggests that even long-term practice may not notably change most physical markers of overall health, however. A 2012 study published in the Journal of Exercise Physiology compared long-term practitioners who had more than 1 year of Bikram practice experience with short term practitioners who had less than 3 months of practice. After multiple tests that measured resting blood pressure, heart rate, pulmonary function and aerobic fitness, the researchers concluded that there was no notable difference between the two groups.
Ultimately, if you believe in Bikram and feel that it's making changes in your life and health, then it's a valid option for you. It may even inspire you to make changes outside of the yoga studio that will help boost your health. But, how long it will take for the practice to make you feel this way — if it ever does — is subjective and impossible to guarantee.
Read More: Can You Lose Weight by Doing Bikram Yoga?