Resting Metabolic Rate, Activity Factor, Non-Exercise Activity Thermogenesis: How does it add up?
What is a resting metabolic rate? Term that is often used interchangeably with Resting Energy Expenditure, and it is the largest component of your daily energy budget. It represents how much energy your body burns at steady rest. It does not include any exercise or non-exercise activities that you do during the day.
So what is Activity Factor
Your activity factor is the number meant to represent how much physical activity that you participate in during the day. The more exercise and physical activity you do with more intensity, the higher your activity factor will be. This number is then multiplied against your RMR or BMR to give you a better estimate of your Total Energy Expenditure for the day.
Example of an Activity Factor chart:
Little or no exercise, desk job, 1-1.2
- Lightly Active
Light exercise/sport, 1-3 days/week, 1.375
- Mod. Active
Mod exercise/sports 3-5 days/week, 1.55
- Very Active
Hard exercise/sports 6-7 days/week, 1.725
- Extr. Active
Hard daily exercise/sports & physical labor job or 2x day training, 1.9
So what is Non-Exercise Activity Thermogenesis?
- Normal daily activities
- Everything you do during the day that is not sleeping.
- Examples include:
- Yard work
So what is the thermic Effect of Food?
The amount of energy expended by the body in processing food intake for use and storage. When you eat a whole food, your body must do work and burn calories to break food down and absorb the nutrients from it.
Energy Balance vs. Your Goals
The direction of your energy balance can be determined by comparing your energy intake to your energy expenditure. If your energy intake exceeds your energy expenditure, your energy balance will tip in the direction of weight gain. If your energy expenditure exceeds your energy intake, your energy balance will tip in the direction of weight loss. If your energy intake is equal to your energy expenditure, then your energy is equally balance and the result will be weight maintenance.
It is important to know how much energy you are expending daily, so that you can plan your energy intake to match.
If your goal is weight or muscle gain, the amount of energy/calories you are taking in should be more than what you are burning during the day. If your goal is weight loss, the amount of energy/calories you are taking in should be less than what you are burning during the day. If your goal is weight maintenance, the amount of energy/calories you are taking in should be equal to what you are burning during the day.
It is important to understand how much energy you are taking in and how that relates to how much energy you are expending during the day. Figure out the direction of your energy balance and see if it matches with your goals as it relates to weight and performance. This will create the base of your focus as you work to achieve your goals We will then discuss further details in later weeks as we go into nutrient and hydration breakdowns.
Without changing your normal diet routine, record your food and beverage intake in application of your choice for at least 3 days: (2 weekdays and 1 weekend day)
- At the end of each day note your total daily caloric intake.
- At the end of the week or 3 day, calculate your average caloric intake.
Create an activity journal:
- Take note of all your activities during the day.
- This should include: exercise, work activities, walking, yard work, house chores, etc.
If you need a better calculation of your energy out/metabolic needs: