Here we go, it was from Zatsiorsky:
So because of that, I'm trying to go as close to failure as possible without actually failing on my back up sets (I don't have a spotter usually). For calf raises, DB bench presses, RDL's, lateral raises, pull ups, that stuff is fine to fail on. Squats and bench presses, not so much. I squat far out from the rack because the set catches are too high and won't let me go ATG.
What's confusing to me however is this... I was initially under the impression that training with light loads for speed (30-50% 1RM) did a good job of training the CNS and improving explosive strength via rate coding, muscle fiber recruitment, etc. However, according to that chart, only the smaller and slower muscle fibers are recruited with lighter loads and lower reps. It appears that it doesn't take into account effort...
I'm pretty sure if you bench an empty bar with maximum speed, youre recruiting more fast twitch/large MU than lifting the bar slowly. I know it won't stimulate hypertrophy in those larger MU's, but nonetheless aren't they recruited? But now that makes me wonder. What if I lift my 12RM just 9 times, but I do it with 100% effort each time? Would that second column in the chart still be accurate?
Regardless, the best rate coding and recruitment gains come from squatting 1-3RM and plyos anyway, according to Zatsiorsky and Verkhoshansky. So I actually see absolutely no benefit in training for RoFD by lifting lighter loads. Leave that to the heaviest sets and to plyometrics.
