What Is Your BMR?
BMR stands for Basal Metabolic Rate. This refers to the number of calories your body requires to function at rest, while not doing anything at all other than breathing and keeping your organs ticking over. Think of this as what your body requires to literally sit in bed all day, not moving at all or eating anything. Your BMR can be used to determine how many calories you need to consume every day, depending on whether you want to lose fat, maintain or gain weight.
It is possible to calculate your BMR for yourself using an formula called the Harris-Benedict Equation:
Men: BMR = 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) – (5.677 x age in years)
Women: BMR = 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) – (4.330 x age in years)
Once you have used this calculation, you can use the result to estimate your total daily calorie expenditure (which also takes into account the thermic effect of food, any exercise you do, daily activities such as walking, cleaning the house etc):
- Sedentary lifestyle: if you tend to do no exercise, multiply the number by 1.2
- Slightly Active: if you do light exercise one to three days per week, multiply it by 1.375
- Moderately Active: if you exercise for three to five days per week, multiply it by 1.55
- Very Active: if you do intense exercise six or seven days per week, multiply it by 1.725
- Extremely Active: if you do exercise every day and have a physical job, multiply it by 1.9
What affects my BMR?
It is important to take into account the factors that can affect your BMR – genetics, age, gender and body composition can have significant impacts on the figure.
While the other factors are difficult to influence, you can actually change your body composition and therefore change your BMR – by increasing your muscle mass and decreasing your body fat percentage, you are able to increase your BMR (boosting your metabolism) and eat more without gaining fat! This is the case as lean muscle mass burns more calories at rest than body fat. This also explains why men generally have a higher BMR than women, as their body size is usually larger.
A great way to increase your muscle mass is to focus your workout routine around resistance training – progressive overload is key here in order to increase your muscle mass, so lifting a heavier weight every week.
How can I use my BMR to help me reach my fitness goals?
If you are looking to lose fat, you require a calorie deficit. To achieve this, knowing your BMR is really helpful and can help you achieve fat loss efficiently.
A calorie deficit can be reached by decreasing the amount of calories you are consuming or increasing your daily caloric expenditure, or both!
If you want to increase the number of calories you are burning each day (calorie expenditure), you can make slight tweaks to your routine which over time will really make a difference.
Examples of increasing your daily expenditure could include walking at least 10,000 steps a day, taking the stairs instead of the escalator, getting off the bus a stop early, or adding in an extra workout a week.
Burning more calories than you consume will create a calorie deficit, meaning you will lose fat. Consuming more calories than you burn creates a surplus, which can lead to fat and muscle gain.
Hopefully this helps you understand what your BMR is and how you can use it to reach your fitness goals, whatever they may be!