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From what I understand, muscle power derives from the product of the force of the muscle times the contraction velocity.

It is quite obvious regarding the general idea for how one increases the force a muscle generates, i.e. via common hypertrophy methods.

How does one increase the contraction velocity component of power? I just don't understand the basic idea even how one would do that so something theoretical or just an example would do. Preferably both.

I suspect the answer is plyometrics, but, if so, I don't understand how that would be advantageous to increasing contraction velocity over strength training.

Stan Shunpike
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    The force causes the velocity trough acceleration. However force output decreases with velocity: https://en.wikipedia.org/wiki/File:Muscle_Force_Velocity_relationship.png. If you only train with low velocity the force will be very high at low velocity but may drop very fast as the velocity increases. The solution is to train over a wide range of velocities so that you can produce as much force as possible at every velocity. – Andy Nov 01 '22 at 07:51
  • @Andy - That sounds like a great answer if you could expand it a little bit into such. Comments are not really for answering questions. – JohnP Nov 01 '22 at 13:42
  • @Andy that sounds very plausible. How do you train at different velocities? Can you give me two examples, one of a low velocity type training and one with a high velocity type training? I'm having trouble envisioning practically what that would look like in terms of exercise – Stan Shunpike Nov 01 '22 at 14:34

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As an example let us consider someone in the bottom position of a benchpress. At time t=0 he starts pressing the barbell upwards and at time t=tl he locks out the press. While pressing he excerts a force upwards on the barbell: F. Gravity on the other hand exerts a force downward on the barbell: mg, where m is the mass of the barbell and g=9.81 m/s^2. The net force on the barbell is: F-mg>=0

According to Newtons 2 law:

F-mg=ma <=> a = F/m - g

enter image description here

So the force the lifter excerts on the bar causes the speed of the bar.

Unfortunately the force output of a muscle decreases monotonically with velocity:

enter image description here

Trought the lift the velocity increases until the force drops down to mg at which time the acceleration is 0 and the bar has reached its maximum velocity. This velocity can be found by taking the intersection between the force velocity curve and a horizontal line where F=mg.

Training at low velocities lifts the curve at low velocities but does little for the curve at higher velocities. The solution is to train over a range of velocities so that you can produce as much force as possible at every velocity you are interested in.

For instance instead of only deadlifting 110 kg for grinding/slow reps you may alternate this with deadlifting 80-90 kgs for explosive/fast reps or powercleans at say 60 kg. In both cases your power production will be larger than with the grinding/slow reps.

Here are some more examples of exercises that works on different parts of the force velocity curve: enter image description here

Andy
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