A recent study published in the Journal of the American Medical Association shows women need 60 minutes a day of moderate exercise to prevent weight gain as they age if they consume a normal diet. This is an increase in exercise time from the current guidelines of 30 minutes five days a week of moderate to intense activity. I don’t know about you, but this seems like a lot! That’s seven days a week! But it really isn’t the whole story.
Basically what the study showed was that women at a normal weight who consume a normal diet can beat middle-age weight gain with 60 minutes of moderate activity such as walking, biking or low-impact aerobics. Or they can work out intensely for 30 minutes a day, whether by running, swimming, or high-intensity aerobics. Because previous guidelines were designed to prevent disease and obtain other health benefits, the team of researchers (led by Dr. I. Min Lee from Harvard) wanted to look at women who weren’t dieting and who were consuming a normal diet, to see what impact physical activity has on weight.
The study looked at 34,079 healthy U.S. women who consumed a usual diet from 1992 to 2007. They were all older than 44 at the start, with an average age of 54. Tracking the women’s activity over a three year period, the researchers found that women gained an average of 5.7 poundsin the study. However those who were normal weight with a body mass index of less than 25, maintained their weight if they exercised 60 minutes a day. Women who exercised less generally gained weight.
Still, this is really not the whole story. The type of exercise we do has an effect on the way we look, and on weight gain. Strength workouts (lifting weights, core exercises, etc.) help to boost metabolism, and keep muscles strong as we age. If we include these types of workouts in our exercise routine, I think we have a better chance at maintaining weight as we get older. People who lift weights or do strength training regularly as part of an exercise routine can preserve most of their muscle mass throughout life, maintain a higher metabolism, and are less prone to weight gain.
The other obvious factor is diet. In this study, researchers spoke of “normal diet”, and I think this ‘”normal” has a range. As we age, diet can play a big role in weight maintenance. Many people eat less as they get older, and many just eat differently. They might start cutting back on fat, eat fewer carbohydrates, or eat more fruits and vegetables. Regardless of how we do it, many of us begin to eat a little better (or smarter) as we get older.
What is the bottom line? Like most things, there is not necessarily one bottom line for everyone. While this recent study did conclude that we probably have to exercise more than we previously thought, as we age, many factors play a role in weight maintenance. Some of the factors are type of workouts, diet, gender, metabolism, genes, stress levels and even mood, just to name a few. However, I think we can come up with a general guide by combining cardio, strength (or core), and diet to truly maintain weight as we age. A basic exercise routine should include cardio, strength training, and flexibility exercises. All of these (together) help you burn calories, build muscle, and keep your connective tissue flexible. Also, eating a sensible diet, keeping sugars and “whites” (white bread, pastas and cereals) to a minimum, and eating a variety of foods, can also help us to avoid weight gain as we age.
What do you think of this recent study and the new guidelines for exercise?