The first study, conducted by researchers at the Colorado State University, investigated the impact of Bikram yoga on physical fitness in young, healthy adults. Twenty-one participants were randomized to yoga training or a no-treatment control group. The yoga training, offered 24 times over eight weeks, was comprised of the standardized Bikram sequence: 90 minutes of supervised postures performed in a heated, humidified yoga studio. Yoga participants exhibited improved strength, lower back, hamstring, and shoulder flexibility, and modestly decreased body fat in comparison to control subjects. In contrast to other research, no changes in handgrip strength were observed. In congruence with existent studies, the yoga group showed no improvement on cardiovascular measures, or maximal aerobic fitness. While interesting, this study had a very modest number of participants, limiting our ability to determine how generalizable the results may be.
The second study, a pilot evaluation of Bikram yoga on sleep, was conducted by researchers at Massachusetts General Hospital and Washington University. Thirteen participants were followed over a 13-day period to determine differences in sleep on days where yoga was practiced compared to days yoga was not practiced. The subjects’ caffeine and alcohol intake, other exercise, naps, and yoga practice were not limited. To measure sleep, the researchers administered both headband sleep monitors and diary reports. While they found standard measures of sleep to be unaffected by yoga, they found yoga to be associated with a significantly faster return to sleep following nocturnal awakenings. In other words, people who awakened in the middle of the night—and had practiced yoga that day—fell asleep more quickly. This study is also limited by its small number of participants as well as the absence of a control group.
The third study, conducted by researchers from Australia and Boise State University, assessed the impact of eight weeks of Bikram yoga (minimum of 20 yoga sessions) in fifty-one university students. Participants demonstrated improvements in mindfulness, perceived stress, cardiorespiratory endurance, flexibility, and balance. This study is limited by its lack of control group.
Bikram yoga is especially well-suited to research due to its standardized pose sequence and the constant of the physical environment. A major issue for yoga researchers is the widely divergent posture flows and sequences, inclusion of diverse components (asana, meditation, pranayama, shavasana, philosophy) and varied environmental effects across lineages and teachers. While Bikram’s aggressive trademarking and standardization has made few friends in the yoga world, it has rendered Bikram yoga ideal for scientific study.
Have you found Bikram yoga beneficial in improving your health?
