Unlocking the mysteries of BMR vs. Resting Metabolic Rate is important because how the human body functions can be overwhelming; especially when it comes to figuring out how many calories we burn when resting.
The two most common terms associated with this are Basal Metabolic Rate (BMR) and Resting Metabolic Rate (RMR). Although these terms are often used interchangeably, they have some key differences that are worth understanding.
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What is BMR?
Basal Metabolic Rate (BMR) is a powerful way to understand your body’s needs! It tells you the exact number of calories that your body burns when it is completely at rest, which helps you maintain vital bodily functions like breathing, circulating blood, and keeping your temperature regulated. It is essentially the energy your body needs to keep functioning while you’re asleep or at complete rest, without taking into account any physical activity or digestion.
BMR is affected by various aspects such as age, gender, height, weight and body composition. Unfortunately, it tends to decrease with age as lean body mass decreases and fat mass increases. Men typically have a higher BMR compared to women since they more muscle mass.
What is RMR?
RMR is comparable to BMR, however it goes beyond that by accounting for your body’s energy output even when you’re not active and in the process of digestion. It’s usually measured once you’ve had an uninterrupted sleep, and includes calories burned during food digestion as well.
RMR is affected by many of the same factors that affect BMR, including age, sex, height, weight, and body composition. However, RMR tends to be slightly higher than BMR because it takes into account the calories you burn during digestion.
What’s the Difference?
BMR and RMR are two different terms which measure the amount of energy your body needs, however there is a slight difference. BMR does not include the energy consumed for digestion and metabolism, making it slightly lower than RMR.
Another difference between BMR and RMR is the way in which they are measured. BMR is typically measured in a laboratory setting, under strict conditions, while RMR can be measured in a more relaxed setting, such as a doctor’s office.
Why is it Important to Know the Difference Between BMR and RMR?
Even the slightest differences between BMR and RMR can be critical when it comes to managing your weight and losing it. It’s important to keep this in mind while making dietary changes. Knowing your BMR or RMR can help you determine how many calories your body needs to maintain its current weight, and how many calories you need to consume to lose weight.
For example, if you know your RMR is 1,500 calories per day, you can create a calorie deficit by consuming fewer than 1,500 calories per day to lose weight. Alternatively, if you know your BMR is 1,500 calories per day, you can create a calorie deficit by consuming fewer than 1,500 calories per day plus the calories burned through physical activity.
Knowing the difference between BMR and RMR is incredibly beneficial in understanding your body’s specific energy needs and reaching your weight loss targets. It can also help you make the most of your health journey! BMR is the minimum number of calories needed by your body to keep functioning but RMR takes it a step further.
It includes the calories you burn through digestion, making it a bit higher than BMR. Knowing your BMR or RMR can help you understand how much to eat in order to reach your weight loss goals and create an efficient calorie deficit.
Factors That Affect BMR and RMR
As mentioned earlier, there are several factors that can affect both BMR and RMR. These factors include:
- Age: As we age, our BMR and RMR tend to decrease due to a decrease in lean muscle mass and an increase in body fat.
- Sex: Men generally have a higher BMR and RMR than women due to their larger muscle mass.
- Height and weight: Taller people and those with more body weight generally have a higher BMR and RMR due to the increased energy needed to support a larger body.
- Body composition: This plays an important role in determining your basal metabolic rate and resting metabolic rate. Generally, people with increased lean muscle mass have a higher BMR and RMR than those with a higher percentage of body fat.
- Genetics: Some people are born with a higher or lower BMR and RMR due to their genetic makeup.
How to Calculate BMR and RMR
As mentioned earlier, BMR is typically measured in a laboratory setting, under strict conditions. The test involves resting in a comfortable, temperature-controlled room for a period of time, typically 12-24 hours.
Measuring your oxygen consumption and carbon dioxide production during this time is a great way to accurately determine how many calories your body is burning at rest. It’s an efficient and easy way to jump-start your fitness journey.
RMR, on the other hand, can be measured in a more relaxed setting, such as a doctor’s office. To measure RMR, you will typically fast overnight and then sit or lie down for a period of time while your oxygen consumption and carbon dioxide production are measured.
There are also several online calculators and formulas that can estimate your BMR and RMR based on factors such as age, sex, height, and weight. However, it’s important to keep in mind that these estimates may not be as accurate as laboratory or clinical measurements.
Implications for Weight Loss
Knowing your BMR or RMR can be helpful when it comes to weight loss, as it can help you determine how many calories you need to consume in order to lose weight. It is vital to remember that the weight loss journey is complex and several factors apart from diet and exercise can contribute to fluctuating weight.
In addition to calorie intake and expenditure, factors such as sleep, stress, hormones, and genetics can all play a role in weight loss. Therefore, it’s important to take a comprehensive approach to weight loss that takes all of these factors into account.
Just a small difference between BMR and RMR can make all the difference when it comes to successful weight loss. Learning about their respective roles and how they relate to your body can empower you to create an effective and sustainable weight management plan that’s tailored for you!
