Why Does My Stomach Look Bigger if I Work Out?

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Your stomach may appear bigger after you work out because you're looking at yourself with a more critical eye.
Image Credit: Kiattisak Lamchan / EyeEm/EyeEm/GettyImages

It's not uncommon to experience a frustrating phenomenon when exercising: Even with a regular workout routine, your stomach may seem bigger after exercise. Figure out the root cause by examining the factors involved and then alter your behaviors or perceptions to minimize the bulge.



Your stomach may seem bigger after a workout because you're looking at yourself with a more critical eye.

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Curb Your Appetite

Exercising doesn't automatically result in weight loss or a trimmer, tighter physique. Many people continue to gain weight over a period of regular exercise due to an increase in appetite. Eating more calories will result in gradual, consistent weight gain, and it's likely that many of those extra calories will show up around the midsection, especially as you age.

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You will need to eat steadily to support your workouts but not excessively. The Academy of Nutrition and Dietetics recommends getting the right proportion of macros to keep weight gain under control: Protein should compose 10 to 35 percent of the total calories you consume; fats, 20 to 35 percent; and 45 to 65 percent from carbohydrates, according to the American Council on Exercise.

Muscle and Weight Gains

People who incorporate core training or weightlifting into their exercise routines may experience some weight gain due to increased muscle mass. The fibers in your muscles tear and while they heal and become even bigger muscles, they are soothed by fluids surrounding them, according to the Cleveland Clinic.


Although it's unlikely for your stomach to look bigger after exercise, it is possible as greater superficial muscle definition is one result of core workouts. Body changes will differ among individuals.

Read more: 13 Benefits of Weightlifting That No One Tells You About

Perception Is Not Reality

It's possible for people to perceive their stomachs as bigger after a workout even if there is no physical change in size. Especially after starting a new workout routine, many people are hyper-vigilant about any changes in their body size or looks, and that increased awareness may result in them taking notice of a change that is not actually present. In some cases, a person's stomach may actually be growing trimmer and toner, but the changes are so gradual that they remain unnoticeable.


Down the Road

It's common for people to experience expanding belly fat or notice bigger waistlines as they age, according to Harvard Health Publishing. Both women and men lose some lean muscle mass and gain body fat as they grow older and their metabolism slows. Harvard Health points out that as your body composition changes, it's possible to notice a bigger midsection even if you haven't gained any weight. Heredity and genetics may also play roles.


Read more: The 3 Secrets to Losing Belly Fat

Prevention and Solution

It's impossible to narrow down a single cause of an expanding belly because everyone's bodies and physical conditions are different. Before changing your diet or exercise program, talk with your doctor.


Doing more vigorous aerobic exercises can help burn off extra weight around the midsection, and adding a regular routine of core moves to your workout can tighten stomach muscles. Perform the plank, the abdominal bridge, crunches and the quadruped because they tone multiple core muscles simultaneously.