Tuck hip problem/

I can hold tuck planche for 30s, and never did adv. frogstand. Last night i held adv. frogstand for the first time, and got 60s, but noticed my hips were really strained, not my leg muscles, back, or abs, but my hips flexors. how do i strengthen these, without holds of adv frogstand (becuase i wish to continue only on tuck ) . my hips dont even hurt when i train adv. tuck planche.

any help is appreciated

L sit, HLL, almost all core work will hitthe hip flexors. Most likely you are not used to holding such a tight position. ADV frog does seem to be harder on the hip flexors than the other planche progressions, at least to me. Adv Frog is going to be harder than ADV tuck for hip flexors since you are obviously not using the hip flexors very much from adv tuck on.

Straddle L is also REALLY hard on hip flexors, probably harder than L sit.