Last week, I explained to Kat how she should supplement her regular yoga sessions with some weight-bearing aerobic exercise, to better serve her heart and bones. I promised I’d explain just what “aerobic” entails and how she might accomplish her new goals without joining another gym.
“Aerobic” simply means “with oxygen.” Like a house equipped with both central heat and space heaters, our bodies have two distinct systems for generating energy for physical activity. For quick bursts, like lifting weights or sprinting, we burn sugar without oxygen. For more prolonged activity, the more fuel-efficient “aerobic” system comes into play, wherein we use oxygen to break down stored carbohydrates and fats. Performing such activities on a consistent basis is what yields the myriad benefits described last week.
How much and how often? Many health and fitness “experts” make this seem far more complicated than it is. Too much talk of “maximum heart rates,” “target heart rates” and “fat-burning zones” may scare away more would-be exercisers than it helps. Exercise becomes aerobic about at the point where you feel mildly “winded.” If you continue at that intensity for 20 minutes three times a week, you begin to reap rewards. Recent studies also show that the workouts can be broken up into even smaller segments and still be effective. Up to a point, increasing the intensity, duration and frequency of exercise increases the benefits. These principles are neatly summarized in the joint statement from the American College of Sports Medicine and the American Heart Association that you can find by searching online for ACSM Physical Activity Guidelines.
Certainly, facilities that offer treadmills, swimming pools or bicycle “spinning” or aerobic dance classes are effective ways to get your needed workouts. However, any sustained effort that gets you a bit winded will yield similar benefits.
And don’t forget sports like tennis or basketball. One unexpected benefit I derive from the last two decades of growth of specialized fitness facilities is that they’ve attracted enough devotees that I rarely have to wait anymore to get onto a public tennis or basketball court!
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