T Nation

Stretch Shortening Cycle vs IB


I Bodybuilder suggests to use explosive reps, concentric being as explosively as you can whilst eccentric being as fast as is safe. Even adding a slight "drop" to the end of the rep.
Remember the article titled "Four steps to more productive workouts" by Ian King. In the article it proposes that the elastic effect caused by lowering the weight quickly and avoiding any pause (essentially the twitch turnaround/or something technique advised by Thibs) essentially makes the rep near useless in terms of muscle fibre recruitment. In fact if lowering the weight for a 1 second count, a 3 second pause before lifting the weight is necessary to negate the "assistance" of the strength shortening cycle.
Logically the Ian King article has my backing, I'd like to hear what you guys think


Some like to move more weight with the stretch reflex. Some like to move less weight without it. Some avoid injuries by using a slow tempo. Some refrain from reposting old questions online and instead decide to go to the gym, try a few approaches and decide what works best for them.


There are many solidly build guys out there who've never done paused reps to any serious extent, so it seems safe to say that we can dismiss out of hand the idea that a rep in which you don't pause is useless. More productive? Maybe or maybe not. But saying they're useless is absolutist bullshit that is quickly disproved in practice. I have trouble believing that a 3RM set of squats in which I don't pause is not recruiting muscle fibers.


It must have been hyperbole on King's part to suggest that a fast "turnaround" would make a rep "near useless in terms of muscle fibre recuitment. We know from Newton's 1st law of motion (the law of inertia) that more force is required to change the direction of a moving object than is required to move a stationary object. So a fast "turnaround" requires more force to be produced than pausing the rep, and then restarting from a dead stop.

Yes, there is some utilization of the elastic properties of the connective tissues during a fast turnaround, but it's hardly enough to generate sufficient force to quickly change the direction of an 85% of 1RM load. Fast/ballistic muscle contractions (at least if the load is sufficient) recruit all available muscle fibers.