How Fast Do You Lose a Pant Size From Running?

Fat Loss

One short run won't lead to noticeable weight loss, but by exercising regularly and watching your calorie consumption, you can put your body in a calorie deficit. This process leads to fat loss, and a deficit of 3,500 calories will help you lose 1 pound of fat. Even if your goal of exercising is to burn the fat around your waist, it's impossible to specifically target a part of your body for fat loss. By keeping your body in a calorie deficit, you'll lose fat throughout your body, including around your waist.

Losing Weight and Inches

The speed with which you lose weight -- and lose inches around your waist to help you successfully fit into a smaller pant size -- depends on how consistently you can keep your body in a calorie deficit. If you can burn an excess of 500 calories per day, you'll create a week-long deficit of 3,500 calories and lose 1 pound. If you're able to create a daily deficit of 1,000 calories for a total of 7,000 extra calories per week, you'll lose 2 pounds. MayoClinic.com suggests a goal of 1 to 2 pounds per week is attainable. Because you'll lose the weight across your entire body, not just around your waist, the length of time needed to fit into a smaller pant size is difficult to estimate.

Running Calories Burned

According to Harvard Medical School, few exercises help you burn calories at a faster rate than running. The calories you'll burn during your run depend on the pace you're able to sustain. If you weigh 155 calories and run for 30 minutes at 5 mph, you'll burn 298 calories. If you're able to average 6 mph over 30 minutes, you'll burn 372 calories. A person of the same weight who can run at 7.5 mph for 30 minutes will burn 465 calories. Factors such as how active you are throughout the day and how many calories you consume contribute significantly to whether you can reach a calorie deficit, but running daily is an effective way to reach this goal.

Diet and Strength Training

Although your recommended daily calorie intake varies according to your age and how active a lifestyle you have, reducing the calories you consume is important if you wish to create a calorie deficit and lose weight. Instead of counting calories, keep the process simple by taking such steps as avoiding soda, trans fats and alcoholic beverages. Strength training doesn't burn calories as quickly as running, but plays a key role in a well-rounded workout regimen. The more you build your muscles, the more calories your body will burn to help you lose a pant size.