Many people come to yoga for help with back pain, stress, or simply to try out a new form of fitness. But here’s a new twist (pun intended) on what stretching does for your body: New research indicates that flexibility in the body may be related to the flexibility of the arteries, and thereby to cardiovascular health.
The study, published in the American Journal of Physiology, indicates that, among people 40 years and older, the ability to bend over in a sitting position and touch your toes might be correlated with the risk for heart attack or stroke. Inability to perform this simple task could mean that your arteries have lost flexibility and become stiff and rigid.
Healthy arteries are flexible and elastic, which helps keep blood pressure normal. Age-related stiffening of the arteries is a precursor of the loss of arterial integrity, which leads to high blood pressure, a propensity to develop blood clots in the linking of the arteries, and possibly stroke and heart attack.
The study included 526 healthy, non-smoking, normal-weight adults, between 20 to 83 years old. Participants were asked to perform what the researchers called a sit-and-reach test (yoga practitioners will recognize it as Paschimottanasana):Sitting on the floor with their back against the wall and their legs straight, participants reached their arms forward by bending at the waist. Based on how far towards their toes they could reach, study participants were then classified as poor- or high-flexibility.
Sitting on the floor with their back against the wall and their legs straight, participants reached their arms forward by bending at the waist. Based on how far towards their toes they could reach, study participants were then classified as poor- or high-flexibility.
The flexibility scores were then correlated with participants’ blood pressure, cardio-respiratory fitness, and the speed with which pulse beats travelled through the body. The researchers found that trunk flexibility predicted artery stiffness in middle age and older participants, but not in younger participants. Among the middle age and older participants, systolic blood pressure (the peak pressure that occurs as the heart contracts) was higher in people with poor flexibility than in the high-flexibility group.
Why would arterial flexibility be related to the flexibility of the body as we get older? One reason, the researchers speculate, is that stretching starts a physiological chain reaction, which slows down or counteracts age-related arterial stiffening. Muscles are made flexible by collagen and elastin and when the production of these is stimulated through stretches, it may also keep arteries flexible, in turn reducing the risk of heart disease and stroke.