Training ultimate strength without injury a difficult challenge. When searching for ways is to obtain maximum myoelectric activity from the back extensor muscles, we discovered that isometric back extensor exercises do not recruit the full pool of motor units. With some extensor motion, many more motor units fire. For example, maximal effort deadlifts only appear to activate a very limited number of the motor units possible with isometric contraction. There appears to be a "fusebox" in the system that, if overcome, could enhance performance. But the fusebox performs a safety function and subduing this inhibition is at the peril of the athlete. Many superior athletes such as Bill Kazmaier, the "World's Strongest Man" for several years, have trained to activate the maximum number of motor units. Kazmaier, for example, used mental imagery together with clever exercise technique to accomplish this. He trained his ability to image the entire muscle and motor unit pool and potentiate the muscles. He worked to perceive optimal recruitment and complete contraction. With his mind controlling the preparation, goosebumps developed on his skin as he rallied the ability and determination to accomplish the task. A portion of his resistance training was directed towards enhancing the ability to activate every available motor unit. These techniques are described below. Other athletes who need supreme speed-strength developed regimens that incorporate elements to train slow strength, fast strength, concentric strength, eccentric strength, multi-articular complex strength, reciprocal inhibition strength, and "playing position" strength. The motor units recruited are very different within a muscle for each of these tasks. Machines, no matter how well designed or promoted, can never provide the rich environment to create the training challenges needed. Even athletes who perform slow- strength activities make substantial gains in strength with speed-strength training. Most NFL linemen will tell you that you if are squatting slowly then you have too heavy a load. Vasily Alexiev, the great Russian super heavyweight, limited the lifting of competitive loads in practice. Rather, he practiced lifts at great speed and with impeccable form. Ultimately, all athletes training for optimal strength will have to speed-strength train.
Some of this content was based off of work by Zach Cooper, CSCS, a strength coach who works with professional athletes.