How To Calculate Power To Weight Ratio Cycling

Last update: 2021-11-28

Cyclists who struggle as the terrain climbs sometimes refer to "power to weight ratio." In addition, several Grand Tour competitors lay a great deal of significance on this method.

But fortunately, most cyclists' success is not solely determined by their power output. It's also critically crucial to consider how much mass you have to move about, or your bodyweight. Masses must be moved uphill against gravity's influence in order to accelerate or move them faster. Deduced from this, moving a smaller object requires less power.

Power-to-weight ratio, generally stated in watts per kilogram, is equally as important for cyclists who don't ride on completely flat, straight roads. Dividing your maximal wattage (in watts) by your body mass (in kg) yields your power-to-weight ratio (kg).

Dividing your maximal power output (in watts) by your body mass (in kg) will yield your power-to-weight ratio (kg). If a cyclist weighs 65 kilograms and produces 180 watts of maximum sustained power, then the rider's power-to-weight ratio is 2.7 W/kg (often represented as 3.5W.kg-1).

1. How to Calculate Your Power to Weight Ratio

To decide your PWR, dividing your body weight in pounds by 2.2 to change it to kilograms, at that point separate the normal control from a 20- or 30-minute time trial by your weight in kilograms.

Average Power/ Body Weight (kg) = PWR watts/kg

Equal to

Average Power/ [Body Weight lbs./ 2.2] = PWR watts/kg


2. Knowing Power-to-Weight Ratio Per Kilogram

How To Calculate Power To Weight Ratio Cycling

The power-to-weight ratio may not change at all if your power output improves, but your weight also rises. As with cyclists who lose weight, they will see a reduction in maximum power. More information is provided in Table 1, which explains the connection between power, weight, and power-to-weight ratio in cycling. Take a close look at the table, and you'll see that the power-to-weight ratios increase as energy output and bodyweight increase — that is, to the right of the table. Any particular power-to-weight ratio (3W/kg) may be accomplished at much lower pure power levels when the rider is relatively lightweight.

This 80kg rider, on the other hand, may desire a higher power-to-weight ratio. Power-to-weight ratio increases from 3.0 to 3.4 w/kg if he or she loses 10 kg (dropping to 70 kg), which is a greater improvement than maintaining weight and focusing on aerobic fitness to reach 240 watts. Because of this, even if your aerobic fitness remains the same, losing extra body mass (fat) can enhance performance.

3. What makes power-to-weight so important when facing wind and hills ?

How To Calculate Power To Weight Ratio Cycling

The force of gravity must be overcome in order to move mass upward, as we have seen previously. This explains why Power to Weight Ratio Is So Important in Climbing. Despite this, ultimate power is still a crucial component of success.

Using a hill of 7% gradient at 16kph (10 miles per hour) in winds, let's examine the power needs of 70kg and 80kg cyclists riding a 6kg road bike. For an 80kg rider, a power-to-weight ratio of 3.73W is required based on statistics on rolling and airflow resistance. Using the same bike, a 70kg rider only needs 266W of power to climb the same hill at the same speed.

Despite the fact that most of the cyclists' power requirements are a function of their body mass (since they're ascending), both riders have to perform extra effort (i.e. overcome aerodynamic resistance) in order to push the air out of their path. The aerodynamic resistance will increase proportionally with the speed. Power-to-weight becomes less important as a result of this. Real-world riders are likely to have a higher frontal surface area, which increases their aerodynamic resistance even more.

a 70kg cyclist uses 32W less power than an 80kg rider to sustain 32kph. There was also a significant 163W difference between the resistance at 32kph and the resistance at 16kph for both cyclists.

Increased upper and lower body strength will enhance energy transmission to the pedals, boost muscle fiber power, and avoid different forms of discomfort, such as back pain, during lengthy rides.

4. Testing Your Own Power Output