Author - Alex Adams
In a previous blog post I discuss how some key qualities underpin and allow athletes to express the full potential of their skill. Strength is often assumed to be the main priority of a strength and conditioning coach, people wrongly ignore the conditioning part in some cases. When you fully understand strength in its entirety and various forms it is easy to see why as coaches we can become a little bias…

Strength can be broken into several different definitions:

Maximal - force produced irrespective of time and athlete (e.g. deadlift 1 RM)
Relative - force produced relative to athlete’s mass (e.g. deadlift 2x body weight)
Explosive - force produced rapidly from stationary start (e.g. squat jump from stationary)
Reactive - force produced from changing direction (e.g. landing rebound jump)

(Not exhaustive list)

Each can (and should) be trained differently as they rely on different mechanisms for improvement. That said, improving relative strength has a beneficial influence on all other physical outputs. Overall force production increases lead to better economy of movement across the board.

Why we are obsessed with getting people stronger:
When you train for strength increases without trying to grow more muscle tissue (increase strength but not mass - relative strength increase) you are affecting the neural system and connections between brain and muscle. Enhancing the number and size of motor units recruited to produce the force is how people get stronger this way. This is seen as beneficial because the athlete weighs the same, but has access to more force production and so can move their mass more easily and often more speedily. To ensure the speed element is also trained we look to improve rate of force production with slightly different exercises and loading parameters - essentially allowing more acceleration during training.
The most commonly used analogy for these two processes are the metaphor of a car. If you increase a cars engine size and horse power without increasing its weight the car will be much faster. Obviously we can also increase the size of the chassis if we want to but it isn't always helpful. A larger vehicle then needs more horse power to keep moving as fast.
Strength is the foundation of all movement. Force is always required to overcome inertia even my fingers typing this article. The larger the forces involved (running, jumping, landing, tackling etc) the higher the contribution strength makes. More strength means more strength in reserve, less fatigue from each sub-maximal effort, more resistance to external forces (even gravity) and easier control of limbs and trunk.

References:
Poliquin, C., & Patterson, P. (1989). TERMINOLOGY: Classification of strength qualities. Strength & Conditioning Journal, 11(6), 48-52.

Folland, J. P., & Williams, A. G. (2007). Morphological and neurological contributions to increased strength. Sports medicine, 37(2), 145-168.

AagardAagaard, P., Simonsen, E. B., Andersen, J. L., Magnusson, P., & Dyhre-Poulsen, P. (2002). Increased rate of force development and neural drive of human skeletal muscle following resistance training. Journal of applied physiology, 93(4), 1318-1326.