“Up to 50% of adults aged 80 years or older are estimated to be frail, and the global prevalence is expected to rise given the aging of our population,” therefore more interventions are needed to help with frailty, corresponding author Julia Loewenthal, MD, said in an interview.
Yoga integrates across multiple body systems including the musculoskeletal system, nervous system, and others, said Dr. Loewenthal of Brigham and Women’s Hospital, Boston. Previous research has shown that yoga has a positive effect on cardiovascular risk factors, mood, and quality of life, but the effects of yoga on frailty have not been well studied.
“We wanted to evaluate whether [yoga] might help with frailty, since it touches on so many systems, as frailty does,” she noted.
In a systematic review published in Annals of Internal Medicine, the researchers identified 33 randomized, controlled trials of yoga-based interventions including 2,384 adults aged 65 years and older. The studies mainly involved Iyengar or chair-based yoga methods. The study population included community-dwelling seniors, nursing home residents, and individuals with chronic diseases.
The studies assessed the effect of a range of yoga practices on frailty markers including gait speed, handgrip strength, balance, lower extremity strength and endurance, and multicomponent measures of physical performance.
Overall, individuals who were randomized to engage in a yoga practice showed improved gait speed and lower extremity strength, compared with controls who were inactive or received an education intervention, with moderate-certainty evidence. The researchers also found low-certainty evidence in favor of yoga for improved balance and for a composite measure of physical function, and low-certainty evidence in favor of yoga for improved handgrip strength.
The findings were limited by several factors, mainly the heterogenous study designs, populations, and yoga styles, the researchers noted. Other limitations included the small sample sizes, variation in descriptions of the studies’ randomizations, and a lack of data on race and ethnicity of the participants.
Yoga’s role in healthy aging
“Overall, we were not surprised by the results since we have seen similar findings from other mind-body practices such as tai chi,” Dr. Loewenthal said in an interview. “We were surprised by the degree of improvement many of the participants had with gait speed.
“Yoga practices usually include a mix of poses in the standing, seated, and lying-down positions,” Dr. Loewenthal said. Some of the studies in the review also involved chair-based methods with few standing poses, and some involved gentle or slow-paced practices. “We know that many of the practices helped with leg strength, and perhaps they are also helping with coordination between the brain and body for walking.”
The findings suggest that clinicians can view yoga practice in general as part of a strategy to support healthy aging, Dr. Loewenthal said. “While our work looked at frailty markers and not overall frailty, I think it would be reasonable to offer yoga as a strategy along with already-established interventions such as resistance training and the Mediterranean diet, and if older adults are already practicing yoga, this could help them understand how the practice is impacting the aging process.”
There are many styles of yoga that overlap and are related to one another, so it is hard to make recommendations about a single type, said Dr. Loewenthal. Many of the studies in the review involved Iyengar yoga, named for yoga master B.K.S. Iyengar, which focuses on precise alignment and breath and seems to be conducive for older populations. Iyengar yoga also involves use of props such as blocks, bolsters, straps, and chairs, which makes it well suited for older individuals who may have a chronic condition or other limitations.
“Some styles of yoga are very physical and may reach energy expenditure and cardiovascular effects similar to aerobic exercise, but this is generally not the case for most styles of yoga,” she added.
As for additional research, “I think it is important that trials use a validated definition of frailty as an outcome; all of the trials in our study used markers of frailty but did not look at overall frailty,” said Dr. Loewenthal. In addition, it is important to understand how yoga affects people who have different levels of frailty, since previous research shows that those who are the most frail benefit most from physical activity interventions.