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Speed and bodybuilding.

PRECONCEIVED IDEAS.
For more information by papa31.

1 - Notion of power:
The power of a blow is the product of force and speed: P = V*F
    - If we increase the speed, we increase the power
    - If we increase the force, we increase the power
However, increasing the force may reduce the speed and therefore maintain the same power, or even reduce it. Inversely, the speed may reach a maximum even by reducing the load used and consequently, you will lose out on power.

EXAMPLE:
  • If I move a force of 100 N through a distance of one metre in 1 second, the power required is 100 Watt.
  • If I move a force of 120 N through a distance of one metre in 1.2 seconds, the power required is still 100 Watt.
  • If I move a force of 80 N through a distance of one metre in 0.8 seconds, the power required is again 100 Watt.

However:
  • If I move a force of 120 N through a distance of one metre in 1.5 seconds, less power will be required. 80 Watt.
  • If I move a force of 80 N through a distance of one metre in 1 second, less power will again be required. 80 Watt.

The aim is therefore to find the best compromise, Force - Speed, to perform a task with the greatest power.

With the sprint, this means determining the best compromise Amplitude - Frequency to improve the speed of displacement.

2 - Notion of reaction and execution speed:
- The reaction speed determined by the time it takes to start an action is defined by the nervous influx.
It is an intrinsic quality specific to each individual, which is innate and which cannot really be improved.
The effect of coffee and some exciting substances may, for very short periods, improve this reaction time.

- The execution speed determined by the time it takes to accomplish an action is defined by the number of nerve and muscular cells capable of coming into action at a time T.
The number and distribution of these cells are intrinsic components specific to each individual although, to a certain extent, they can be modified.


The "speed" or "strength" muscular fibres are the white fibres.
Their numbers vary from one person to another, making the difference between innate sprinters and innate long-distance runners. This number can be increased, however, since there are cells which have not yet decided where they belong and can go to the red side or the white side.

Muscular work, in strength and resistance, will increase the number of myofibrils present in the white fibres (and increase their volume at the same time) and also 'convert' some still-unspecialised muscular cells into white fibres.

Out of context, this increase is pointless. There is in fact no point in increasing the volume if this produces no significant improvement to your physical and/or sporting abilities.

The main purpose of this work is that, for a given stress, a given nervous reaction, the number of muscular fibres which come into action will increase.

This explains why to increase your execution speed, you must increase your muscular mass.

N.B.: One disadvantage, however.
- The increase in strength is always accompanied by an increase in the volume and weight. You have to know when to stop so that the increased strength is not hindered by too much muscle volume and too much weight, especially for the speed of displacement.

- Increasing the muscular mass implies increasing the energy expense. So, for a minor effort, a bodybuilder will expend more energy than a marathon runner.
Which also means that he will get tired more quickly.