If you have a little extra fluff around your midsection, you're far from alone: Many people find themselves getting a little bigger around as they age. The good news is that any cardio workouts you can squeeze into your day will help you burn that belly fat away, although exactly how much cardio you must do depends on many factors, with one of the biggest being your diet.
For many, eating a nutrient-rich and calorie-appropriate diet and doing about 60 minutes of cardio most days of the week is enough to lose weight. However, weight loss is a complex mechanism that's not entirely understood. If you're not seeing the results you want, track your calorie intake and increase the length or intensity of your physical activity.
A Word on Belly Fat
What goes on under the skin of your abdomen isn't quite as simple as it might seem. Belly fat comes in two varieties: The soft subcutaneous fat that lies just under your skin, and visceral fat, which pads the space between your internal organs. You need some of both for a healthy body, but having too much can elevate your risk for many health problems, including heart disease, high cholesterol and triglycerides, and even some cancers.
Although scientists don't understand the mechanism exactly, they consider visceral fat to be more of a health risk than subcutaneous fat. Happily, both types of belly fat respond to a calorie deficit, or burning more calories than you take in. You can establish a calorie deficit by increasing your level of physical activity or decreasing your calorie intake. But most of the subjects in the National Weight Control Registry report that they lost weight — and kept it off — by using a combination of both methods.
Your Eating Choices Matter
How much cardio you must do to lose that belly fat depends, in large part, on how you eat; that's because it's easy to accidentally undo all your hard physical work by making poor choices in the kitchen. You can support your hard work, instead, by focusing on the key elements of healthy eating habits. These include eating plenty of fruits, vegetables and whole grains; focusing on high-quality protein options such as fish, poultry, nuts and seeds; and limiting your intake of sodium, added sugar and unhealthy saturated fats.
You don't necessarily have to count calories to lose weight — just making healthy eating choices and doing about an hour of moderate- to vigorous-intensity cardio per day might be enough. And if you're really "on" with your diet, you can probably lose weight with less physical activity. But if you want to calculate how much cardio a day you should be doing, counting calories is a must.
The U.S. Department of Health and Human Service (DHHS) provides estimated calorie intakes according to age, gender and activity level. You can use this to calculate how many calories you need to maintain your current weight. For example, an active 25-year-old woman needs about 2,400 calories per day, while an active 50-year-old woman needs about 2,200 calories per day.
The National Institutes of Health recommends reducing your calorie intake by 500 to 750 calories/day to see a weight loss of approximately 1 to 1.5 pounds per week, but you can supplement that — or replace it — with an increased calorie burn from doing cardio.
The National Institutes of Health notes that women can usually lose weight safely on a diet of 1,200 to 1,500 calories per day, and men on a diet of 1,500 to 1,800 calories per day. While it may be tempting to cut even lower than that, your body needs a certain amount of calories and nutrients to stay healthy and fuel all that physical activity. So, never go lower than those minimum intakes without the guidance of a medical professional.
Cardio for Weight Loss
So, now that you know what sort of calorie deficit you're looking at in the kitchen, it's time to see how your cardio workouts fit into the picture. Ideally, you should be doing at least 30 minutes of moderate-intensity physical activity on most days of the week, anyway, to meet the DHHS recommendations for physical activity to stay healthy. If you're eating appropriately, this might be enough to help you lose weight; but most people will see success and have it happen faster if they do more exercise. A goal of 60 minutes of moderate-intensity (or more) exercise per day, at least five days a week, is a good target.
How can you tell how many calories you're burning? Your favorite fitness or calorie counting app is the ideal tool, but make sure you're honest about inputting how much you weigh, how hard you're working out and for how long; both have a definite impact on how many calories you burn.
Although any typical physical activity contributes to your calorie burn for weight loss, some types of cardio are better than others for burning belly fat. These include:
Brisk walking. Walking is one of the simplest, most inexpensive, and most easily accessed types of cardio, and even a few walks a week can have a notable impact on your belly fat. In a small but notable September 2014 study published in the Journal of Exercise Nutrition and Biochemistry, researchers followed 20 women, half of whom walked three times a week for 50 to 70 minutes per session, while the other half acted as the control group. At the end of the 12-week period, the group who walked had a significant decrease in belly fat, but the control group did not.
Running. Like walking, running is easily accessed as long as you have the appropriate shoes. And it yields very impressive calorie burns: For example, according to estimates from Harvard Health Publishing, if you weigh 155 pounds and run for an hour at 5 mph (equivalent to a 12-minute mile), you'll burn almost 600 calories.
Cycling. Any of the exercise machines in the gym will help you lose belly fat if you use them conscientiously; you can even buy versions of these machines for use at home. Of these machines, one of the most effective calorie burners is the stationary bike; Harvard Health Publishing estimates that a 155-pound person pedaling vigorously for half an hour will burn more than 450 calories.
Whatever your choice of cardiovascular workout, consider adding sprint intervals for an extra boost to your weight loss efforts. They're a time-tested way to do more work in less time, and a meta-analysis published in February 2018 in the New Zealand journal Sports Medicine found that high-intensity intervals were an effective means of reducing body fat, including abdominal and visceral fat.
Get a Baseline
So, how's that weight loss program going? Paying attention to how you feel and how your clothes fit are two of the easiest ways to track your progress. But you can also use objective measures, such as quick-and-easy measurements of your waist circumference.
To take your waist circumference, wrap a flexible measuring tape around your bare belly, right across the belly button. That number not only tells you how your workouts are going, it can also speak to your health: If your waist circumference is at or above 40 inches for women or 35 inches for men, you fall in a high-risk category for weight-related health problems. But if you keep up a healthy diet and doing an hour or more of cardio most days of the week, that belly fat is on its way out.
- Harvard Health Publishing: "Abdominal Obesity and Your Health"
- Harvard Health Publishing: "Abdominal Fat and What to Do About It"
- National Weight Control Registry: "NWCR Facts"
- Health.gov: Dietary Guidelines for Americans, 2015-2020: Appendix 2. Estimated Calorie Needs per Day by Age, Sex, and Physical Activity Level"
- National Institutes of Health: "Healthy Eating Plan"
- Health.gov: "Dietary Guidelines for Americans, 2015-2020: Appendix 1. Physical Activity Guidelines for Americans"
- Journal of Exercise Nutrition and Biochemistry: "Effect of Walking Exercise on Abdominal Fat, Insulin Resistance and Serum Cytokines in Obese Women"
- Harvard Health Publishing: "Calories Burned in 30 Minutes by People of Three Different Weights"
- Sports Medicine: "Effect of High-Intensity Interval Training on Total, Abdominal and Visceral Fat Mass: A Meta-Analysis"