Cycling BMR Calculator
Use the Cycling BMR Calculator
BMR Calculator
Daily Calorie Intake
| Activity Level | Calories |
|---|---|
| BMR: Basal Metabolic Rate | 0 |
| Sedentary: Little or no exercise | 0 |
| Light: Light exercise/sports 1-3 days a week | 0 |
| Moderate: Moderate exercise/sports 3-5 days a week | 0 |
| Active: Hard exercise/sports 6-7 days a week | 0 |
| Very Active: Very hard exercise/sports & physical job or training twice a day | 0 |
| Extra Active: Super hard exercise/physical job & training twice a day | 0 |
Exercise: 15-30 minutes of elevated heart rate activity.
Intense exercise: 45-120 minutes of elevated heart rate activity.
Very intense exercise: 2+ hours of elevated heart rate activity.
Want to know your cycling training zones?
Basal Metabolic Rate (BMR) is the amount of energy your body needs while resting in a neutral environment, with your digestive system inactive. Think of it like figuring out how much fuel a car uses while idling in park. In this state, energy is only used to maintain essential organs, such as the heart, brain, kidneys, and lungs. For most people, about 70% of the total calories burned each day goes to basic body functions. Physical activity accounts for around 20% of daily calorie burn, and about 10% is used for digesting food (thermogenesis).
BMR is measured under very strict conditions while you’re awake, requiring complete rest. This makes BMR the largest part of a person’s total daily calorie needs. To find your daily calorie needs, the BMR value is multiplied by a factor based on activity level, ranging from 1.2 to 1.9.
In most cases, BMR is estimated using mathematical formulas based on statistics. The Mifflin-St Jeor Equation, introduced in 1990, is considered one of the most accurate methods for estimating BMR. The Katch-McArdle Formula is slightly different because it considers lean body mass, making it potentially more accurate for people who are lean and know their body fat percentage.
Here are the two formulas this calculator uses:
Mifflin-St Jeor Equation:
- For men:
BMR = 10W + 6.25H – 5A + 5 - For women:
BMR = 10W + 6.25H – 5A – 161
Katch-McArdle Formula:
BMR = 370 + 21.6(1 – F)W
Where:
- W = body weight in kg
- H = height in cm
- A = age
- F = body fat percentage
Factors that Affect BMR:
- Muscle Mass: Building muscle through anaerobic exercises like weight-lifting increases BMR, as more muscle mass requires more energy to maintain.
- Age: As people get older, their BMR tends to decrease, meaning they require fewer calories to maintain basic body functions.
- Genetics: Some people are born with naturally higher or lower BMRs due to their genetic makeup.
- Weather: Colder environments increase BMR, as the body burns more energy to maintain a stable temperature. Excessive heat can also raise BMR as the body works to cool itself.
- Diet: Eating smaller, more frequent meals can slightly boost BMR, while starvation or very low-calorie diets can reduce BMR by as much as 30%.
- Supplements: Some supplements or drugs, like caffeine, can temporarily raise BMR, often to help with weight loss.
Measuring BMR:
While online calculators provide estimates, the most accurate way to measure BMR is through a specialist or a calorimetry device, which is available at some gyms, doctor’s offices, and weight-loss clinics.
Resting Metabolic Rate (RMR):
BMR and Resting Metabolic Rate (RMR) are often used interchangeably, but they differ slightly. RMR is the energy your body uses when you’re at rest, but not under strict conditions like BMR. RMR is usually measured in less controlled settings, making it more practical but slightly less precise.
Modern Understanding:
A 2005 study showed that even when all known factors affecting BMR are controlled, there’s still about 26% variance between people that can’t be explained. This means that while BMR calculations are useful estimates, they aren’t 100% accurate. Tracking your daily activity, diet, and progress in a journal is often the best way to adjust and meet your health goals over time.