Mark,
in light of what has been said here in this thread regarding long rest times, and this ^, would you like to take a stab at what's going here.
Spit balling:
Science is wrong (Again) about how much time it takes for ATP to recharge, maybe there's a much wider variance across individuals. ????
I just don't know, Fulcrum. ATP recharge may not be the only variable in play, and that cannot be very surprising. And I don't see why understanding the precise mechanism matters to the application. If you are doing 465 x 5 x 5, you will probably need 15-20 minutes between sets if you intend to make all 25 reps, and I know this to be true absent any explanation of why.
Well, today's workout was a success. Squats, Bench, and chinups all improved as was expected going in. In the future, the first thing I'll do when I hit a snag like that again is turn up the rest minutes some. And I will also resist the urge to hunt down and smack the PE weightlifting instructor who said 3 freaking minutes would suffice for heavy strength training. Of all the bad info out there, set rest times has got to be one of the most perplexing to me. If I go looking anywhere but SS or an SS-derivative they never recommend more than 5 minutes. Even the SS knockoffs don't seem to wanna recommend more than 5. It's like they are deliberately setting everyone up to fail.
It makes sense if you think about it. If you rest for 24 hours between sets, some fatigue will generally dissipate beyond what you get in the first eight minutes. Same for an hour. Why not for twenty minutes? Some of it is definitely psychological, too; when I get under the bar, I don’t want the thought at the front of my mind to be any version of “boy, that was tough” before I start my set.
I work a pretty intense job, lots of travel and very few weeks under sixty hours. I still make time to rest for up to fifteen minutes between my work sets, depending on how much they beat me up. It’s just a few extra minutes at the gym, really.