Glossary
Tempo
Tempo is the speed of a lift — how long each phase (lower, pause, lift, pause) takes.
Often written as four digits like 3-1-1-0: three seconds down, one second pause, one second up, no pause at the top.
Related terms
Eccentric
The eccentric phase is the lengthening part of a lift — when the muscle resists while being stretched.
Concentric
The concentric phase is the shortening part of a lift — when the muscle contracts to move the weight.
Time under tension
Time under tension is how long a muscle spends under load during a set.