Exercise and Fitness Tips to Improve Your Health
Get answers to your questions about exercise, and tips for getting the most from your workouts.
Are you getting started with an exercise program? Hoping to improve your
existing routines or find new workout options? Did you know that a complete
plan consists of three basic elements: aerobic fitness, muscle
strength/endurance and flexibility? How do you assess your current fitness
level before you begin? How do you know how much exercise you should do, or
whether you should see a doctor before you start?
Our Healthy Living channel provides in-depth answers to these questions,
along with guidelines to help you develop a fitness program that's right for
you. With these exercise and fitness tips, you can learn to gauge how hard and
how often you should exercise, and get yourself started on the road to better
Q. Why do you use the BMI, and is it useful for weight lifters?
The Body Mass Index
(BMI) is a simple way for men and women to estimate body fat based on their
height and weight. From the BMI, it is possible to determine your healthy
One of the limitations of BMI is that it can overpredict overweight or
obesity in people who are lean and muscular. For instance, someone who is 5
feet 10 inches tall and weighs 220 pounds, with 12% body fat, would be
considered obese based on BMI standards. Obviously, someone with 12% body fat
is not obese.
The scientists who developed the BMI guidelines readily admit to this
limitation. But their rationale is that most Americans are not lean and
muscular and so for most people, the BMI is an accurate assessment of body fat
and increased health risk.
It is important to know that people who are classified as overweight or
obese can still be healthy as long as they are fit. In one well-known study,
fit people with BMIs that classified them as overweight or obese were healthier
and lived longer than unfit people who were at normal weight.
The BMI, for the majority of Americans, is the most up-to-date and
scientifically sound method available for determining healthy weight.
Q. Does aerobic exercise interfere with muscle gains from weightlifting?
If you're training for an endurance event like a marathon, when you might
run 60 miles or more per week, you'll almost always see a decrease in your
muscle mass. For most of us, who do more moderate amounts of physical activity,
there will be minimal, if any, loss in muscle mass -- so there's nothing to
If you do plan on lots of aerobic exercise and are concerned about losing
muscle, try starting with 20-30 minutes of moderate aerobic exercise (at 50% to
70% of your maximum heart rate) two to three days per week, and see how it