Understanding F₀ and v₀

There are multiple variables calculated from force/velocity profiling with the two main outputs being and . These two, and other variables, are calculated from velocity development during a linear sprint where weight and height of the runner, air resistance and pulling force (if applicable) are included.

• F₀ (Force Intercept):
  represents the theoretical maximal horizontal force the athlete could produce when starting from rest (i.e., at zero velocity). This value reflects the athlete’s force-producing capability.

• v₀ (Velocity Intercept):
  is the theoretical maximum sprinting speed that the athlete could achieve if the force output dropped to zero. Although no athlete actually reaches , it serves as a benchmark for their speed potential.

Together, these parameters help coaches and sport scientists evaluate whether an athlete is more force- or velocity-oriented. Example, a sprinter with a high but relatively lower might benefit from training that enhances speed mechanics, while an athlete with a high might focus on developing more force production during the start phase.

Relationship between F₀, v₀ and power

The relationship between and is linear with the peak power () output at 50% of the .

Figure 1: Combined F/v plot showing both force and power as a function of speed. Force and power are both adjusted for body weight.