Tempo is often a common variable that is overlooked during most trainee's programs. Altering the speed of a repetition will make a huge difference in how difficult that movement becomes. If you don't believe me try performing a pull up or push up with proper form in 3 seconds up , 1 second pause, and 3 seconds down fashion each repetition and see how your reps are cut in half.
It is advocated that a person should exercise smoothly,rhythmically, and without haste, but no so slowly that the mere holding of the weight would tire the person. A momentary pause at the end of each repetition is advocated.
There are many tempo schemes out there, nautilus traditionally uses a 2/1/4 scheme , which translates to 2 seconds concentric phase, 1 second pause, 4 second eccentric phase. Another popular one is 3/1/3. The whole purpose is to affect the stretch shortening cycle. A stretch-shortening cycle (SSC) can be defined as an active stretch (eccentric contraction) of a muscle followed by an immediate shortening (concentric contraction) of that same muscle. It has been postulated that elastic structures in series with the contractile component can store energy like a spring after being forcibly stretched. Slowing down the reps will allow one to control for things like momentum which relies on physics to get the job done , then on muscular strength.
The pause is important in order to dispel that inherent elastic component in the muscles ( think rubber band effect) when an exercise is performed quickly; which allows one to rely on elastic energy to propel oneself up and thus make the the exercise easier. For example while performing squats while lowering yourself , you feel a stretch at the bottom position and take advantage of that to lift more weight , you may be doing yourself a disservice since you are in fact doing less muscular work.
Example Tempo's for different goals
Symbols X = Explosive , or As Fast as Possible
Maximal Strength: 85-100% of your 1RM
So the tempo would be X- 2- 3 , assuming concentric phase, pause, eccentric phase, if it is an exercise that works in reverse order for example squats than just reverse order the tempo so it would be 3 -2 - X
You can play with the pause period from 1s pause up a 4s pause.
Strength and Size: 75-85% of your 1RM
Tempo would be; 4-1-4 slower if the intensity is closer to 85% , or 2-1-2 if the intensity is closer to 75%
You can have a longer pause for pulling movements , i.e. pull up pause 2s
Hypertrophy: (60-75% of your 1RM)
Tempo would be; 4-1-7 if intensity is closer to 75% , and 2-1-3 if intensity is closer to 60%
Pause in the stretched: 0-1 second (longer pause for pulling movements)
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Slow eccentric , causes you to apply a very high level of force , on the other hand a fast eccentric is advantageous for maximal strength or plyometrics when wanting to recruit the fast twitch muscle fibers and give the nervous system a break between each explosion. One method is not superior to the other , so it would be optimal to alternate between each method, for example on a 2 day strength training regimen one day can be slow tempo , and the other day can be faster tempo.
