On New Year's Eve, many of us made a promise to ourselves, or to our partners, that we'd get healthier and lose a little weight in 2016.
That means getting active and getting off the couch, but preferably after this story.
David Marcus ran three marathons, but that was more than a decade ago. Since then he's had trouble fitting fitness into his busy life.
"I have a demanding job, family, and by the time I get home from work at night I just don't have the energy," he says.
Now, at age 45, he is recommitting to an exercise routine.
"I just want to be healthy so I can be there for my kids for as long as I can. I believe I need to have at least four days out of the week with an hour a day – vigorous exercise, you know, building up a sweat."
Guidelines suggest 75 minutes of "vigorous" aerobic activity or 150 minutes of "moderate" activity weekly.
Vigorous activities include running, jumping rope or playing squash – activities where you can't say more than a few words at a time. Moderate activities include brisk walking, dancing or biking, where you usually can talk but not sing.
"Exercise makes you live longer, makes the quality of your life better," says Dr Leslie Cho.
Dr Cho directs the Cleveland Clinic's Women's Cardiovascular Center.
"As you age, it helps your blood pressure, improves your glucose control so you don't get diabetes, and your cholesterol level is lower."
Your heart rate is another way to gauge activity level. Start with 220 and subtract your age. Moderate activity is 50 to 70 percent of that number – for a 50-year-old a heart rate of about 85 to 120.
Watch the video for the full CBS News report.
