Yoga Flexes Muscle for Those With High Blood Pressure

Yoga provided extra blood pressure (BP) lowering and other benefits when added to a regular exercise routine, a small pilot trial showed.

At one exercise rehabilitation center, hypertensive patients who were randomized to an additional 15 minutes of yoga, in lieu of extra stretching during supervised training sessions, showed improvements at 3 months in terms of:

• BP: -11/8 mm Hg from 130/77 mm Hg with yoga vs -4/3 mm Hg from 126/76 mm Hg with stretching (P<0.001)

• Heart rate: -7 from 73 beats/min vs -3 from 74 beats/min (P<0.001)

• Reynolds Risk Score: -1.2 from 8.2 vs -0.6 from 9.0 (P<0.05)

Otherwise, yoga and stretching conferred similar decreases in lipid, glucose, and high-sensitivity C-reactive protein levels and Framingham risk score on top of a program of aerobic exercise training in a primary prevention cohort followed by Paul Poirier, MD, PhD, of Quebec Heart and Lung Institute at Laval University, and colleagues.

For now, "it remains unclear whether the scientific community considers yoga to be a form of physical activity and would include it as a recommended form of exercise to improve health-related outcomes in replacement of stretching. Nonetheless, we provide support that yoga should be considered an important component of an exercise training regimen program," the authors wrote in the Canadian Journal of Cardiology.

"As observed in several studies, we recommend that patients try to find exercise and stress relief for the management of hypertension and cardiovascular disease in whatever form they find most appealing," Poirier said in a press release. "Our study shows that structured yoga practices can be a healthier addition to aerobic exercise than simply muscle stretching,"

Guidelines do not currently endorse yoga for primary prevention. According to national recommendations, adults are advised to do 150-300 minutes of moderate exercise or 75-150 minutes of vigorous exercise each week along with muscle and strength training twice per week to achieve the most benefits of physical activity.

In the U.S., cardiac rehabilitation is a component of secondary prevention and usually includes medically supervised exercise training, education, and psychosocial support for myocardial infarction (MI) survivors, people who have had heart surgery, and people with heart failure.

A larger randomized trial, Yoga-CaRe, had shown yoga-based cardiac rehabilitation to be safe and effective in improving quality of life and return to preinfarct activities after acute MI. Due to lower than anticipated event rates, however, the study was underpowered to prove yoga's effects on mortality and other hard outcomes.

Other researchers have also experimented with other alternatives to usual exercise, such as tai chi and high-intensity interval training, with varying success.

Unfortunately, the benefits of cardiac rehab continue to be hindered by low participation nationwide due to cost and other barriers.

For the present study, Poirier and colleagues screened for hypertensive patients presenting to a regional lifestyle and cardiovascular prevention exercise rehabilitation center. People with coronary artery disease or heart failure were excluded, as were those with hypertensive end-organ damage and those taking medications or supplements that affect BP, cholesterol, or inflammation.

The investigators managed to recruit 60 patients (mean age 63 years, 70% men) for random assignment to 15 minutes of yoga or stretching on top of a usual exercise program lasting 30 minutes, five times a week, for 3 months. Baseline characteristics were well matched between the two groups.

Study results were subject to potential misclassification due to hypertension being diagnosed based on office BP measurements and defined as ≥140/90 mm Hg for three measurements on different days.

More importantly, as a whole, the medical literature is limited by inconsistencies and ambiguity in defining yoga practice for exercise and health, Poirier and colleagues said.

"There is large variation in existing yoga practices, particularly modern postural yoga practices. This variability makes it difficult both to report the prescription and dose of yoga and for researchers to evaluate the effects of yoga, because interventions are often poorly described and reported," the researchers noted.

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