For
optimal gains, you need to
perform each exercise according to the prescribed tempo code — the first digit refers to how long (in seconds) it should take you to
perform the eccentric part of the rep (lower the
weight), the second digit indicates how long you should pause
at the bottom of the movement, the third how long it should take you to
perform the concentric part of the rep (lift the
weight) and the fourth tells you how long you should pause
at the top portion of the movement.