Hey
the iliopsoas muscle is one of the major contributing muscles involved in improving sprinting speed, but the question arises in training this intriguing muscle group.
I have heard that it is just not possible to increase the cross sectional area (the size) of the psoas muscle, that maybe its just something that is genetics, while there are some who say it can be increased through decline situps or leg raises.
I found this interesting article.
http://www.just-fly-sports.com/best-of-strength-and-conditioning-research-in-august-part-i-studies-on-the-psoas/
If increasing size was possible, most of effort would be put on increasing size, before strengthening it.
what do you guys think.
yo. i'm 100% sure you could hypertrophy it to some extent.. as much as quads, glutes, or traps? I doubt it..
and ya I would focus more on the ~10+ rep ranges for targeting the hip flexors. I definitely wouldn't recommend really heavy training with that muscle group - sounds like a great way to cause problems/strains. The hip flexors aren't primarily anti-gravity muscles so, no need to go crazy with them in terms of intensity.
Regardless of whether size is possible or not, hit with the 10-20 rep range .. IMHO.
Unweighted or slightly weighted static holds are also pretty damn effective.. have to be careful with those though, a bit more risky than safe, clean, light reps.
pc!!