How Many Days a Week Should I Do Cardio to Lose Weight?

Combined with a calorie-controlled diet, aerobic exercise is your BFF when it comes to weight loss. But how much is enough to see results? That depends on a lot of factors, including the type of cardio you do and how healthy your diet is; Knowing how all the different factors at play affect your cardio needs will help you plan and stick to an effective exercise program for weight loss.

The main requirement for losing weight is creating a calorie deficit — or consuming fewer calories than you expend each day. Your daily calorie expenditure supports many functions — physiological ones, such as breathing, and daily activities of living, such as the energy expended at your job, carrying groceries and walking up the stairs to your bedroom. These can all affect how much exercise you need.

For example, if you have a very active job, you'll likely need less supplemental cardio exercise than someone with a desk job.

Cardio exercise burns calories while you are doing it, and it's the area you have the most control over when it comes to calorie expenditure. You can exercise more or less, for a longer or shorter duration and at a lower or higher intensity, all of which will burn different amounts of calories. It's up to you to decide how much weight you want to lose and how quickly, and then create a calorie deficit to reach those goals.

To set your initial goals, you can use the general 3,500-calorie rule. This says that for every 3,500 calories you burn or cut from your diet, you'll lose one pound of fat. So, if you created a calorie deficit of 500 each day by burning 250 calories with cardio and cutting 250 calories from your diet, theoretically, you would lose around one pound of fat each week.

Keep in mind that calorie burning and weight loss aren't exact sciences, and the 3,500-calorie rule may or may not be accurate for everyone. How much cardio you need to do to lose weight depends on a myriad of factors, including your genetics, medical conditions and medications, age and gender.

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Setting goals can help you determine how many days a week you should do cardio. A good place to start is with the U.S. Department of Health and Human Services (HHS) Physical Activity Guidelines, which recommend a minimum of 150 minutes of moderate-intensity exercise or 75 minutes of vigorous exercise each week.

This is the lowest amount of time determined to provide all the benefits of cardiovascular exercise, including weight management as well as the control and prevention of certain chronic diseases, such as heart disease and Type 2 diabetes. It's not only beneficial for you to plan to meet weekly goals for weight loss, but it will also improve your overall health.

Moderate-intensity activities include brisk walking (about 4 mph), bicycling at an easy pace (10 to 12 mph), playing doubles tennis and dancing. Vigorous activities include jogging or running, hiking uphill, aerobics, competitive sports, fast cycling and swimming.

Whether you choose to aim for 150 minutes of moderate activity or 75 minutes of vigorous activity, you can split it up however you want. You might decide to take a 30-minute brisk walk five days a week, or run for 25 minutes three days a week.

Keep in mind that these are the minimum goals. Getting more cardio exercise than this brings you even more benefits for your weight and health. According to the HHS, a better goal is to strive for 300 minutes of moderate-intensity or 150 minutes of vigorous-intensity exercise weekly, which will help you burn more calories and lose more weight.

Let's say you're planning on shooting for that 300-minute goal, and you plan to reach it with brisk walking. Many people will choose to do an hour of cardio five days a week, but you could also do a little over 40 minutes seven days a week, or 75 minutes four days a week. It depends on your schedule.

How many calories will you burn? You can wear a heart monitor for a more accurate count, or you can use estimates from Harvard Health Publishing. In 60 minutes, an average 155-pound person can burn approximately 334 calories walking at a pace of 4 mph. Calorie burn depends on your weight; the heavier you are, the more energy you have to expend — at least in the beginning, until your body adapts to these demands.

All things remaining equal, walking for an hour five days a week would burn 1,670 calories per week, enough to lose a little less than half a pound of fat. How does that stack up to your goals? Were you hoping to burn more each week?

If so, you will need to choose a more intense activity, such as running — which can burn around 600 calories an hour if you maintain a pace of 5 mph. If you did that five days a week, you'd burn roughly 3,000 calories, which would bring you closer to losing one pound of fat per week.

However, it's probably not a good idea to run for five hours a week because it places a lot of stress on your body. Instead, you could cross-train with other vigorous activities, such as fast cycling and swimming laps.

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But many people don't have the time or inclination to exercise vigorously for an hour five days a week. If that's you, don't worry about it. You're still going to reap a lot of benefit from even half that amount. However, you will have to pay more attention to your diet.

Cutting out sugary, fatty and processed foods will automatically reduce your calorie intake — significantly, if you consume a lot of those foods. Increase your intake of fresh fruits and vegetables, lean protein, whole grains, and healthy fats from fish, olive oil, nuts and seeds.

Nutritious foods tend to be lower in calories than junk food — you can eat more and feel more satisfied while still maintaining a calorie deficit. You'll also have more energy to slay your cardio workouts as many days a week as you choose to do them.