Cycling Calories Calculator

The Mechanics of Cycling Metabolism

Cycling is a highly efficient form of locomotion because the bicycle supports the rider's weight, significantly reducing the energy cost of moving vertical mass compared to Running. However, as speed increases, the primary obstacle becomes **Aerodynamic Drag**. Over 90% of a cyclist's energy at speeds above 30 km/h is spent pushing through the air. This Cycling Calorie Engine factors in velocity-specific MET values to estimate the caloric cost of your ride.

For those looking to maintain a specific Weight Target, cycling is the gold standard for high-volume, low-impact exercise. To optimize your performance, ensure you are tracking your Cardiac Training Zones to target fat oxidation (Zone 2) or aerobic threshold (Zone 4).

The Cubic Relationship of Drag

In physics, the power (Watts) required to overcome air resistance is proportional to the **cube** of the velocity (v³). This means that to go twice as fast, you need eight times more power. This is why the caloric burn difference between 15 km/h and 35 km/h is so dramatic. Competitive cyclists who sustain high speeds must produce massive amounts of energy (and therefore burn massive amounts of calories) just to maintain their momentum against the wind.

Real-world Power Output (Watts)

While METs provide a clinical estimate, many cyclists now use **Power Meters** to measure their actual mechanical output in Watts.
- **Watts to Calories:** A general rule of thumb is that 1 Watt for 1 hour = ~3.6 kJ of work. Because the human body is only about 20-25% efficient at converting metabolic energy into mechanical work, the number of Joules spent is roughly equal to the number of Calories burned.
- **Example:** Maintaining 200 Watts for 60 minutes results in roughly 720 kJ of work and ~720 kcal burned.

Factors Affecting Your Burn

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Frequently Asked Questions (FAQ)