I dont like his 20 sec iso hold at the top neither but his other exercise where you just do weighted standing knee raises and hold the top for 2-3 seconds ifor 8-10 reps is what worked for me in the past to conpletely rid my groin pain during sprinting. These exercises are not necessarily slow twitch. If youre using proper intensity to be challenging for 20-30 seconds, its still max strength and not endurance. You dont call 30 sec weighted planks slow twitch do you just cause theyre an iso? If bodyweight is too easy, just add weight to the iso hold for hip flexors.
Hanging or captains chair knee/leg raises work well too focusing on getting the thigh above parallel. If ur gym has cable machines with an attachment that can be hooked onto ur foot, u can do cable knee drives. Look em up on youtube.
Yeah I'll add in some hip flexor stuff on my dynamic weight room day. I'll try out everything and see what I like best.
If youre using proper intensity to be challenging for 20-30 seconds, its still max strength and not endurance. You dont call 30 sec weighted planks slow twitch do you just cause theyre an iso?
These next few paragraphs are overly theoretical, i'm probably wrong about everything.
I honestly am not so sure i agree with you about this. 30 seconds is a long time. I have never done weighted planks where i collapsed under 25 seconds, but if I tried to do a weighted plank where I collapsed at 10 seconds, the weight would probably be A LOT higher than a plank where I collapsed at 25 seconds. That's the sort of exercise i could see as max strength. But it's really difficult to load up a plank to that extent without the plates sliding off each other.
I think iso's are even worse for max strength because the same fibers are being trained. In a concentric or eccentric movement, the joint angle changes, which means that different clusters of muscle fibers are being trained. At the top of a squat, there might be more lower quadricep activation, at the bottom of a squat there might be more upper quad fibers activated or whatever. But in an iso movement, the joint angle doesn't change, so the same fibers are being trained, IMO this leads more towards slow twitch.
Anyway this discussion is more about IIB(X) fibers, which have few mitochondria, fire fast, and recover very slowly. These types of fibers are used at high intensity power output. I think the type of muscle fibers that would be most beneficial for hip flexors would be IIA, because they are best adapted for fast, repetitive, low intensity movement, which is the way I see the swing phase in running. Apparently bodybuilders have a high amount of these fibers. Almost all the information from this last paragraph is from Supertraining by Verk.
So, IMO, for hip flexors iso's would be ok, but i dunno about other muscles.
1/16
BW:176
20 min jog
SL-RDL (L,R): 135x5, 155x4,5 (failed one on the left leg..what the fuck), 135x5, 155x5
DL con, SL ecc calf raises (2 min breaks): 135x5, 225x5x2, 205x5x2
Squat (3min breaks): 245x5, 265x4x5, 275x5, 285x5
5RM PR, 5x5 PR
Eccentric adductor raises: 90secsx3,
Si reset circuit: x3