We are launching a new workout next week at the studio, Metabolic Disruption. The goal of this workout is to disrupt and enhance your metabolism. This workout should increase the calories immediately burned post workout, called excess post-exercise oxygen consumption (EPOC). If done effectively, this increase in calories burned can last for up to a day after your workout. I thought since we were discussing metabolism, I would share what exactly makes up your metabolism. Some of you reading this may feel, “I’ll never lose fat because of my slow metabolism.” Hang in there, you may not be a bad as you thought.
To understand metabolism, you have to understand just a few basic terms. The energy your body burns in a day is called your total daily energy expenditure (TDEE), which has three components: resting metabolic rate, thermic effect of food, and activity energy expenditure.
Your resting metabolic rate (RMR) are the calories your body burns to stay alive. This makes up approximately 70% of your TDEE. Now there are people who burn calories at an elevated rate, also known as people with a “fast metabolism”, but their advantage is not as high as you may think. Most people (68%) stay within 8% of the average RMR. The majority (96%) stay within 16% of the average. Simply put, 96% of all people stay within 200- 300 kcal of the average RMR.
Your brain and visceral organs require 91/200 kcal/lb./day. That’s a lot of calories compared to the needs of your skeletal muscle at rest, which require 6 kcal/lb./day. Your fat stores require the least amount of energy, 2 kcal/lb./day. So, what does all this mean? I’ll use myself to explain the math.
On the low side, 91 kcal divided by my approximate brain weight (3.4lbs) and organs (approximate 40 lbs.) x 100 yields 209 kcal daily. On the high side, 200 kcal divided by my brain weight and approximate organ weight x 100 yields 460 kcal daily. My brain functions and organs combined burn between 209-460 kcal.
Then there is the thermic effect of food (TEF). This is the energy used to ingest, absorb, and metabolize your food. As cited in this research article*:
“TEF represents about 10% of the caloric intake of healthy adults eating a standard mixed diet, but your actual number will depend on various factors, such as your lean body mass and the size and composition of your meal. The energy required to digest each macronutrient (its TEF) can be expressed as a percentage of the energy provided by this macronutrient:
· Fat provides 9 Calories per gram, and its TEF is 0–3%.
· Carbohydrate provides 4 Calories per gram, and its TEF is 5–10%.
· Protein provides 4 Calories per gram, and its TEF is 20–30%.”
This gives merit to why eating more protein can help promote fat loss, while maintaining lean muscle mass. Protein burns, by far, the most of the three macronutrients.
The final piece of your metabolism is where we help at the studio. Your activity energy expenditure (AEE) is the most varied of the three parts. It includes all physical activity and spontaneous physical activity. This piece can make up between 15- 50% of your daily energy burn.
Can you increase or elevate your metabolism? Yes, and exercise is the best way. But note, you want to focus on increasing the calories from EPOC to stoke the fire in your fat burning machine.
I’ll see you at the studio.
*Tappy L. Thermic effect of food and sympathetic nervous system activity in humans. Reprod Nutr Dev. 1996;36(4):391-7. doi: 10.1051/rnd:19960405. PMID: 8878356.