We expend energy (burn calories) through three main pathways:
- Resting Metabolic Rate (RMR) – 60-75% of energy expenditure. The energy used by all of the vital processes and organs throughout the body.
- Activity Energy Expenditure (AEE) – 17-32% of energy expenditure depending on your activity levels, and includes exercise and NEAT. NEAT stands for non-exercise activity thermogenesis, and is the energy used for everything that is not resting, eating or exercise. It ranges from walking, typing and house jobs to fidgeting.
- Thermic Effect of Feeding (TEF) – approximately 8%. The energy used to process, digest, absorb and distribute foods/nutrients.
It is extremely common for those who lose weight to regain the weight lost quickly, and this is not surprising due to several physiological adaptations that occur. Lets take a look at what changes physiologically and why this may lead to the weight re-gain:
- A decrease in resting metabolic rate (RMR), which results in less energy being used to sustain bodily functions.
- An unconscious reduction in exercise and activity (AEE) decreasing total energy expenditure.
- An increase in efficiency during exercise. Therefore, the energy used during exercise is significantly less as the body becomes more efficient.
- An increase in appetite due to changes in hormone levels such as ghrelin and leptin that increase your desire to eat.
Recommendations for Maintaining Weight Loss
- The diet used to facilitate weight loss has to be sustained, if you return to your previous eating habits you will regain the weight lost.
- Therefore, choose a diet that is realistic and you can adhere to.
- There must be a conscious effort to increase activity and exercise (AEE) to compensate for the unconscious decrease in exercise and increase in efficiency (less energy used during exercise).
- Increasing protein intake has a large satiating effect (makes you feel fuller for longer), and can result in a reduced food/calorie intake.
- Spacing your meals out throughout the day and increasing protein intake can offset feelings of hunger.
- Ensure your diet contains a wide variety of foods to avoid deficiencies.
About the Author
Mark Funnell holds a BSc (Honours) degree in Sport and Exercise Science and an MSc in Sport and Exercise Nutrition from Loughborough University. He is currently working as a Performance Nutritionist for the England and Wales Cricket Board with both the England Women’s Academy and Midlands Regional Disability Cricket squads. Additionally, Mark is a graduate member of the Sport and Exercise Nutrition Register (SENr), an ISAK Level 1 Anthropometrist and a UK Anti-Doping advisor.