By now, it’s no secret that exercise is crucial for keeping your heart healthy and reducing your risk of coronary heart disease (CHD) and countless other diseases. Like every muscle in your body, your heart needs to be worked out and challenged in order to stay strong and keep ticking.
Questions still remained, though, about exactly how much physical activity is required to significantly lower your risk of CHD. So researchers at the Harvard School of Public Health set out to find an answer.
In their meta-analysis of 33 studies that correlated exercise and reduction of CHD risk, nine included adequate quantitative data of physical activity. After review of those studies, the researchers found that those who engaged in moderate-intensity exercise for 150 minutes (two and a half hours) per week — which, according to federal guidelines, is the minimum amount of exercise we should be getting — experienced a 14 percent reduction in CHD risk compared to those who didn’t exercise at all.
And the participants who engaged in moderate-intensity exercise for 300 minutes (five hours) per week had a 20 percent lower risk of CHD.
Interestingly, the association between the amount of exercise and heart health was greater in women than men. Among the people who exercised 150 minutes per week, the men saw a 9 percent reduction in CHD risk and women had a 20 percent reduction in risk, compared to their sedentary counterparts. And among those who worked out 300 minutes per week, the men saw an 18 percent reduction in risk and the women saw a 28 percent reduction, compared to the non-exercisers.
The best news to come out of this analysis, however, is that even the people who exercised for a mere 75 minutes per week — less than 15 minutes day — still experienced a 14 percent reduction in CHD risk. 
How to Fit in Daily Exercise for Heart Health
The results of this meta-analysis should come as welcome news for those who find it hard to fit exercise into their jam-packed schedules. If you’re one of those people, strive to move for 15 minutes most days of the week, and you’ll do yourself and your heart a tremendous favor.
Remember, there are countless forms of exercise. If you dread going to the gym or walking on a treadmill, try an exercise DVD, go for a walk or jog around your neighborhood, or try yoga, Pilates, or strength- or circuit-training. Even chores around the house, like vacuuming, scrubbing the shower, and gardening can be turned into a workout if you make it strenuous enough!
It’s also important to note that you don’t have to do it all at once. Getting four 15-minute mini-workouts can have the same heart-protective benefits as a full hour-long workout.
In addition, look for unique opportunities to fit exercise into your daily life. Here are some ways to do that:
- Take a 15- or 20-minute stroll at lunchtime or after dinner with your spouse, friend or dog.
- Always take the stairs instead of the elevator or escalator.
- Ride your bike to work or to run simple errands.
- Play with your kids or grandkids in the park or in your yard.
- Park as far away as possible from the entrance of a store.
- Do sit-ups, push-ups, lunges or squats while watching TV.
- Every hour, get up and stretch or walk a lap around your office.
 Sattelmair J et al. Dose response between physical activity and risk of coronary heart disease. Circulation. 2011;123, 789-795.