Lifting weights isn’t just a case of moving load from A to B. We have to consider the specific actions of the muscle group/target tissue during movement. Let’s consider the muscles of the rotator cuff. Their job is to decelerate the humerus during shoulder tasks, such that much of their loading comes during the eccentric (lengthening) phase of movement. So when loading those muscles, it is not wise to rip through the concentric (shortening) phase, to then have an uncontrolled eccentric phase. Better practice would be the addition of a pause between the two phases, and a focus on a slow and controlled deceleration of the load during the eccentric phase.
Lifting tempo should also be manipulated when increasing muscle size (hypertrophy) is the goal. It’s a technique that’s been made popular by the bodybuilding community and is based on the notion of “time under tension” and is again based on a slow and controlled eccentric phase. There are occasions during rehabilitation where rebuilding muscle hypertrophy is important (post-surgery, for example), so manipulation of lifting tempo is an important consideration if that is the working goal.
It is also important to vary the tempo as we become more sport/function specific. Sport is almost all about maximal power – i.e. producing high levels of force in as short a time as possible. When structuring a rehabilitation programme, it is important to consider tempo in relation to the stage of rehabilitation and the current working goal. Adding speed is just as important during late stage rehabilitation as removing speed during early stage rehabilitation.
We can also see improvements in force production and lifting techniques by altering the tempo of transition between the eccentric and concentric phases of a lift. Think about squatting heavy, that feeling of struggling to drive out of the “hole” (bottom of the lift). By altering the percentage of the load, and inserting a pause of predetermined length at the bottom of the movement, the athlete has to develop higher levels of maximal force to drive the weight up, rather than relying on the elasticity of the movement.
Lifting tempo is manipulated by the strength and conditioning community based on the athlete’s goals and sports specific requirements. However it still remains an under used tool in the rehabilitators toolbox.
Lift smart, not without forethought.