Mend Physical Therapy Blog and Injury Information

Why Can’t I Lose Weight With Exercise?

March 23, 2021


America has seen a steady increase in body weight over the past decades with the CDC reporting 2 in 3 American adults can be classified as overweight or obese. Many of these individuals report attempts at weight loss by creating a caloric deficit through diet and exercise, but have been unable to achieve or maintain their desired weight. Among those who choose exercise many struggle to achieve their desired weight loss goals because of the body’s remarkable ability to conserve energy.

Humans have evolved over time to survive and thrive through many different time periods, environments, and challenges. Our body’s have learned to conserve energy through reduced activity and increased caloric intake to help withstand periods where less food is available. In our current society, thankfully most individuals will not face these external challenges. Instead, Americans face the challenge of trying to lose weight in an environment of food abundance and technological advances reducing our daily activities.

Reduced caloric intake is the most effective method for weight loss due to its’ relative ease of creating a caloric deficit compared to exercise. For example, consider cutting out 500 calories of food or beverage compared with 30 hard minutes on a stationary bike. Researchers continue to investigate the challenges of weight loss with exercise and specifically the strategies our bodies use to avoid losing weight through physical activity. Energy compensation occurs when our body reduces its’ resting metabolic rate (less caloric burn), physical activity, and/or, increases our appetite in response to exercise.

Researchers have shown up to 50% of the calories burned during an acute bout of exercise can be compensated through the day. Thus exercisers can lose up to half of the caloric benefits, not health benefits, of an individual exercise session. Thankfully, additional research has shown how we can get around these compensations by adjusting exercise parameters including intensity and duration. Authors have shown at least 300 minutes of aerobic exercise, twice the CDC current recommendation, may be required to overcome the body’s compensatory strategies and create significant lasting weight loss. This lack of duration is one of the most common mistakes individuals make when trying to lose weight with exercise.

Individuals are encouraged to work with a physician on medical interventions, nutritionists on dietary strategies, but also use longer duration aerobic and strength training exercise sessions, consistently over time, to achieve their weight loss goals.

Click Here to learn which exercises are best for your weight loss goals