Which Comes First, Cardio or Weights_ - Alex Hutchinson [54]
The point here is that it’s very difficult to tease apart the mental and physical components of athletic performance. That’s especially true for yoga, a word whose very meaning—“to yoke, or unite”—refers to the goal of integrating body, breath, and mind. “Yoga would say that there’s really no way to affect the mind without affecting the body, and there’s no way to affect the body without affecting the mind,” says Timothy McCall, a San Francisco doctor and author of the 2007 book Yoga as Medicine. Increasingly, though, people are turning to yoga in search of physical benefits. According to a 2008 survey, 15.8 million Americans were practicing yoga, and 49.4 percent of them started with the goal of improving their health (compared to just 5.6 percent in a similar survey five years earlier).
Considered strictly as a form of exercise, yoga has many strengths and a few key weaknesses. A 2001 study at the University of California, Davis, found that an eight-week program of two 90-minute hatha yoga classes per week led to significant increases in strength, muscular endurance, and flexibility. Other studies have found improvements in balance and even bone density. This is not really surprising—yoga is, after all, a weight-bearing physical activity. If you want to know how much you’ll improve, that’s a more difficult question, because there’s such a bewildering array of yoga styles. Like any other form of exercise, the benefits depend on which specific activities you do, how often you do them, and how vigorously.
A more controversial question is whether yoga is vigorous enough to count as aerobic exercise that improves cardiovascular fitness. While the UC-Davis study observed a small but measurable improvement of 6 percent in aerobic fitness, other studies have failed to confirm this. In a 2002 Northern Illinois University study of 45-minute “power” (ashtanga vinyasa) yoga sessions, the participants’ heart rates stayed below the recommended threshold for aerobic exercise. Similarly, a 2007 study found that average energy expenditure during a hatha yoga session was equivalent only to a leisurely stroll, although heart rates did reach a moderate level during the “sun salutations” portion of class.
That doesn’t mean yoga can’t provide a good aerobic stimulus. Karen Rzesutko, the lead researcher in the Northern Illinois study, says she believes an experienced power yoga practitioner “who is motivated enough to give 100 per cent to the practice” can reach and maintain a suitably high heart rate. But at a certain point, it’s probably best to accept yoga’s strengths and weaknesses rather than fight them, and seek your aerobic exercise in other ways. After all, McCall points out, having a balanced approach is a worthy yogic principle—that’s why he hikes, bikes, and dances in addition to doing yoga.
What are the benefits of yoga for overall wellness?
Of the eight “limbs” of classical yoga, formulated over 2,000 years ago, only one relates to physical fitness as we now think of it. The others include ethical principles, the flow of vital energy, and meditation as paths toward self-knowledge and enlightenment. These days, many people have a more casual attitude to yoga. But even if you just drop in to an occasional class, you’ll spend time on breathing and concentration exercises that you wouldn’t encounter in a typical gym routine—part of the discipline’s continuing commitment to a state of wellness defined much more broadly than the usual fitness markers.
Science, needless to say, seeks to classify and measure these benefits. One theory is that yoga helps to control the “fight-or-flight” response that physical, mental, or emotional stress triggers in your body. The stress hormone cortisol, for instance, triggers a cascade of physiologic, behavioral, and psychological effects through the endocrine system; similarly, your nervous system responds to stress by sending signals to elevate heart rate, blood viscosity,