The Risk Factor
As with any physical activity there, exists an element of risk with strength training. However, with judicious care, these can be minimised.
There exists a preponderance of evidence that explosive weight training movements carry a high risk of injury, both acutely and cumulatively, to muscle tissue, fascia, connective tissue and bony structures. There is evidence that acceleration and deceleration forces placed on involved tendons, ligaments, muscle fascia and bone create both initial and terminal stresses on these structures which will likely produce training injuries.
For example, various powerlifting moves; such as power cleans cause repetitive forced hyperextensions of the lumbar spine. This forced hyperextension can cause any number of injuries such as lumber sprain, strain, disc damage or a condition known as spondylolysis. The wrist, elbow and shoulder joints are also at risk of injury acceleration and/or deceleration forces imposed on these areas.
Using momentum to lift a weight increases the internal forces encountered by a given joint: the faster the weight is lifted, the greater the forces are amplified. When the forces exceed the structural limits of a joint, an injury occurs in the muscles, bones or connective tissue.
Dr Fred Allman, past president of the American College of Sports Medicine (ACSM), has commented on numerous occasions about the hazards of introducing speed to weight training movements. He also stated that performing powerlifting movements such as those mentioned above, provides little benefit to those training for any other sport or activity, apart from powerlifting.
Note: The ACSM has been the world’s foremost authority on training protocol since 1954.
It has been shown in various researches that lifting a weight in an explosive fashion decreases muscle fibre recruitment due to momentum and thus any improvements in muscle function.
High-Intensity Training for Strength Vs Size Vs Power
How much muscle you gain vs how much strength you gain over a given period of training is genetic. The belief that you can train specifically for strength or size is a myth, most likely resulting from people trying to compare the strength to muscle ratio between different individuals. On exactly the same training program, you could see people becoming very strong with very little increase in muscle size, or very muscular with low to moderate increases in strength or somewhere in between.
Training Explosively to Develop Explosive Power
The idea that you need to train explosively to develop explosive power is a myth. You do not need to move explosively during an exercise. Your explosive power will increase linearly with your strength, so as long as you are getting stronger, that’s all that matters.