You might be proud of telling your friends how much you lift - but have you ever considered how fast you lift?
The speed of your exercise can mean all the difference between muscle-building success and failure. Slow down and read carefully.
What is it?
Tempo is the technical term for the speed you lift and lower a weight during a repetition. It’s commonly expressed as four numbers, each denoting the time in seconds you should take to complete the four phases of a rep.
The first number is the initial phase of the lift – be it concentric (lifting) or eccentric (lowering). The second is the point of stretch or contraction (often where there is a pause). The third is the concentric (lifting) or eccentric (lowering) phase, and the final number is the stretch or contraction at the top or bottom of the movement.
To perform a dumb-bell curl using a 2/0/4/0 tempo, you take two seconds for the concentric phase (lifting), no pause at the top of the exercise, four seconds on the eccentric phase (lowering), and no pause at the bottom point of the exercise.
Why is it important?
The rep tempo you adopt has a profound effect on how your muscles adapt to training. Your body has mechanoreceptors in joints, ligaments, tendons and muscles, and these monitor your intensity and speed of motion when working out. The force of muscle contraction is not as important as the rate of force production. In other words, choosing the right tempo is even more vital than choosing the right load.
How can I apply this?
Tempo to build strength If your aim is to increase sheer power and strength, employ a fast tempo, such as 1/0/2/0 – where the first phase is concentric (lifting). This takes advantage of the ‘stretch reflex’ – the natural tendency of muscles and connective tissue to spring back to a shortened state after being stretched. When there is no pause between fast eccentric and concentric phases, body adaptations are predominantly at the neuromuscular level – that is, within connective tissue, as opposed to muscle. If you’re using a heavy weight, it may of course move slowly, but you should always aim to shift it explosively if strength gains are your primary goal.
Tempo to bulk up To increase muscle size, focus on a slower lifting tempo – typically 2/0/4/1. This targets growth-prone type II muscle fibres and limits the stretch-reflex component of the lift. The long eccentric phase causes a high amount of microscopic tears in your muscle fibres, which then increase in mass – provided they are allowed appropriate rest and recovery. The one-second pause at the bottom point of the move allows your connective tissues to lengthen and relax: the stretch-reflex is lost and the majority of adaptation thus occurs within your muscles.
Tempo to reduce body fat The Journal of Strength and Conditioning Researchfound that a tempo of 3/1/1/0 (where the first phase is lowering) significantly increased resting energy expenditure (the amount of fat your body burns post-workout) for up to 72 hours after exercise in both trained and untrained individuals. The slow eccentric phase increases the tension on the muscle which then demands more energy (fat stores) in order to repair. Lifting explosively, meanwhile, promotes strength gains which will enable you to lift heavier as the weeks go by.