Here are 5 benefits to training the full range of motion in the weight room:
1) Healthier joints: By moving the joint throughout its entire range of motion, the ligaments and tendons will also be stressed (good stress) to stretch and contract. This will stimulate recovery pathways to reinforce these tissues to become stronger. As well full ROM movement encourages proper joint lubrication to keep the joint mobile.
2) Reduce muscular strength imbalances: By training the full ROM, the muscle will then fully stretch and contract. Ensuring that the muscle retains is full length without shortening. As well the strength throughout the entire ROM will be vastly improved as it will be trained.
3) More Muscle Development: When you train the full ROM in all lifts, you will pack on more muscle and have greater muscular development. Time under tension will increase as will recruitment of Type 2 fibers with the added micro-trauma caused by the greater ROM. More motor units will be called upon to lift the load further stimulating growth and strength.
4) Better Mobility: By training the entire ROM, their will be less tightening of the soft tissue. Leading to much greater joint and movement mobility. At the same time this will prevent the muscle fibres from shortening, maintaining longer muscle belly. This will keep the tissue more elastic and healthy in nature.
5) Reduced Injury Risk: When a muscle and connective tissue is strong throughout its entire ROM it is better developed which then lowers the risk for injury. This will reduce strength and structural imbalances. As well the inhibitory reflex of the muscle will be better trained. The benefit of this is allowing for greater loading at more points in the range of motion. Leading to improvements in neural firing and reduce injury risks at the extreme ranges.
BONUS - Performance: When the full ROM is trained on various lifts it will directly improve athletic performance from sprinting speed, vertical jump to strength. Full ROM training allows for greater strength gains to be made in the long run. Being stronger in the full range will allow for there to be even greater strength and performance improvements in the range specific to the sporting movement. In sports with a multi directional component, this will allow for greater performance in change of direction. Acceleration will improve and the ability to stop and cut will become better as a result.