Which Comes First, Cardio or Weights_ - Alex Hutchinson [73]
Steven Blair, a professor at the University of South Carolina, has performed a series of studies dating back to 1994 that try to distinguish between obesity and physical inactivity as causes of health problems. “When we look at obesity and properly adjust for fitness, the obesity risk goes away,” he says. “It just disappears.” In fact, he says, obese people who are physically fit are half as likely to die as people of normal weight who don’t exercise.
This message is particularly crucial for people who start exercising and soon get frustrated—and perhaps quit—because they don’t succeed in losing weight. As long as they’re meeting basic exercise goals such as half an hour of moderate to vigorous exercise five times a week, Blair says, they’re gaining important health benefits no matter what the scale says. Seen in this light, the Statscan results are less shocking—in fact, they closely mirror the results of a similar U.S. study from 2005, which also found that those carrying a few extra pounds into old age lived longer.
“As you age, you start to lose weight and become frail,” notes one of the Statscan study’s authors, David Feeny of Kaiser Permanente Center for Health Research in Portland. For the elderly, among whom most of the deaths in the study occurred, a few extra pounds may provide a margin of error to help them through the illnesses and accidents that become common at that age. In addition, a more vigilant health care system that watches for warning signs such as high blood pressure may have actually succeeded in lowering the penalty for being obese over the past few decades, Feeny says.
The study doesn’t give obesity a free pass—those with a BMI above 35 were 36 percent more likely to die during the study than those of “normal” weight. But researchers also point out that BMI isn’t the most effective way to measure risky fat build-up. “It’s most useful in population studies,” says Travis Saunders, a researcher at the Children’s Hospital of Eastern Ontario Research Institute in Ottawa whose blog Obesity Panacea covers the latest findings in obesity research. “But if you try to apply it to individuals, it doesn’t work.” That’s because where you store fat is as important as how much you have. Fat in the abdominal region, particularly the visceral fat that accumulates between internal organs rather than fat stored just beneath the skin, is particularly problematic. In contrast, Saunders says, fat on the hips, buttocks, and lower body appears to be less of a concern. For that reason, many doctors now measure waist circumference as a proxy for visceral fat. Ideally, men should be less than 40 inches (102 centimeters) and women should be less than 35 inches (88 centimeters).
It’s also worth remembering that (strange as it may sound) death isn’t everything. The average lifespan is now long enough that conditions like heart disease, hypertension, and diabetes—all of which are strongly linked to being overweight—can have a serious impact on quality of life in your final years. The message of the Statscan research, ultimately, is not that weight is irrelevant but that your focus should be on the ongoing process of living healthily, rather than the potentially misleading endpoint of reaching a certain weight.
BODY MASS INDEX
To calculate your body mass index (BMI), divide your mass in kilograms by the square of your height in meters. For example, a man who is 1.75 meters tall and weighs 75 kilograms would have a BMI of 75 / (1.75)2 = 24.5. (Alternatively, multiply your weight in pounds by 703 and divide by the square of your height in inches.) A BMI between 18.5 and 25 is considered normal weight; below 18.5 is underweight and above 25 is overweight, while above 30 is defined as obese.
Is weight loss simply the difference between “calories in” and “calories out”?
In theory, managing your weight is simplicity itself. If you take in more energy (in the form of food) than you burn (through physical activity and metabolic processes), those