There’s a reason workouts are called cardio: They exercise your heart. Physical fitness, along with a healthy diet, can go a long way toward reducing your risk of heart disease.

If you’re watching your cholesterol numbers, you probably already know that elevated levels of LDL (low-density lipoprotein) and low HDL (high-density lipoprotein) can put you at an increased risk for coronary artery disease.

Luckily, there are a number of ways physical activity can help keep your cholesterol in the low-risk range. Here’s why you should get your heart in tip-top shape, and some pointers on how to do it.

QUIZ: How Physically Active Are You?

Don’t Sit on the Sidelines
Even though you know you’re not doing your body any favors by abstaining from exercise, it’s not like you’re doing damage by cuddling up each night with your remote control, right? Wrong. You’re not just missing out on a chance to improve your health by remaining sedentary; you can actually deteriorate your health and make your cholesterol numbers worse. Think couch potato turned mashed potato.

Cris Slentz, PhD, and William Kraus, MD, both of Duke University Medical Center, have spent the past 10 years studying the effects of regular activity and inactivity on heart health. According to their research, just six months of sitting around doing nothing can significantly increase LDL levels and make that “lousy” stuff even more dangerous.

Try This

Put on a pedometer. Just wearing one motivates people to walk more. Your goal: 10,000 steps a day. Leave the car at home if your destination is a half-mile or closer. When you do drive, take the spot farthest away from where you’re going.

Find Your Fitness Sweet Spot
So what should you be doing for exercise? According to Slentz, that may depend on your particular lipid profile — meaning whether, for instance, you have low HDL, high LDL or high triglycerides. Certain levels of exercise appear to affect different types of cholesterol in the body.

If you have high triglycerides: Go for a walk. Slentz’s study compared both the amount and intensity of workouts, and found that modest amounts of moderate exercise had the greatest effect on lowering triglyceride levels. What exactly does modest mean? Pretty much equivalent to walking briskly for 30 minutes five days a week — and the Duke team saw double the drop in triglycerides from doing that sort of exercise versus “vigorous” forms like jogging or biking faster than 10 miles per hour.

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While lower-intensity exercise does appear to be better for controlling triglycerides, it’s important to note that all exercise groups decreased their levels of this lipid, so if you’re more hare than turtle, do the workout that you enjoy the most. 

VIDEO: Where does Cholesterol Come From?

If you need to ramp up your HDL: Take the stairs. When it comes to improving your HDL, more exercise is better. While any kind of exercise is going to boost your good cholesterol, vigorous exercise like jogging or walking up an incline can really make a difference. Remember, any exercise is better than no exercise.

Doing what you love is going to bestow the most benefits, because it’s something you’re more likely to stick with. If walking is your favorite, try adding some interval training — short bursts of intense exercise — like adding some uphill segments or inserting a brief jog into your walk to get your heart rate up.

If you want to lower your LDL: The jury is still out on whether exercise can have any real sustainable effect on lowering your LDL cholesterol. However, Slentz points out that everyone in the sedentary group raised their bad cholesterol, while no one in any of their exercise groups did. So, exercise will at least help you hold the line on LDL while you improve your other cholesterol factors.

—by Jill Provost