Athlete profiling: the force-velocity curve and force-velocity profile

Two athletes can have the same jump height but produce it in completely different ways. One is very strong but slow; the other has low strength but is fast. The force-velocity profile shows this difference in numbers and tells you which direction the program should take.

The force-velocity curve

As the force a muscle produces increases, it contracts more slowly. This inverse relationship forms a curve, and every type of training falls into a region of this curve:

How is the profile built?

The most practical method is the loaded jump test: the athlete performs squat jumps at body weight, then with increasing loads (for example +20, +40, +60 kg). The velocity and force produced at each load are calculated; the points fall along a line. The slope of the line gives the athlete's profile:

• Force deficit: If performance drops quickly as load increases, the athlete's maximal strength is insufficient. The program shifts toward heavy strength.
• Velocity deficit: If the athlete is good at heavy loads but below expectations at light loads, they can't produce their strength quickly. The program shifts toward plyometrics and ballistic movements.
• Balanced profile: If performance is similar at both ends, general development continues.

You can get a rough idea even without lab equipment: comparing estimated 1RM squat with CMJ gives a practical indication of which side is lagging. For details, see our performance testing article .

Programming by profile

Athlete with a force deficit

• 4–5×3 at 85–92% on main lifts
• 2 heavy lower-body sessions per week
• Plyometrics at a maintenance dose (once a week, low volume)
• Duration: 6–8 weeks, then re-test

Athlete with a velocity deficit

• Lightly loaded ballistic movements: jump squat at 20–30%, med ball
• Reactive plyometrics: depth jump, bound, pogo
• Sprint and maximum velocity exposure
• Heavy strength maintained at a maintenance dose

A common mistake: the same prescription for everyone

Most athletes assume they need “more plyometrics” or “heavier squats.” But writing a heavy strength block for an athlete with a velocity deficit slows progress, and piling plyometrics onto an athlete with a force deficit delivers a small return for the tendon load. The profile prevents both mistakes.

How often should it be measured?

The profile is built at block transitions, i.e., every 6–8 weeks. More frequent measurement risks confusing measurement error with real change. During a block, weekly CMJ monitoring is enough as a fatigue indicator.

Frequently asked questions

To get your profile built, book an assessment session .