Today was my first day of football practice, and this year we have added this thing we call "V" sit-ups (might not be actual name) to our daily strength routine. I will attempt to describe them to the best of my ability, but we all know what can get lost in translation:

1)while on the ground flat on your back, spread your leags as far apart as you can.
2) While keeping your legs motionless, sit up as if your were doing a sit-up.

The goal is to strengthen our hip-flexors. Our assistant head coach (also an assistant track coach at a DIII Univeristy) claims that strengthening your hip-flexors translates into increased top-end running speed.

I have two questions: first,is what our coach says about the benefits of strong hip flexors true? Secondly, is the exersise I explained above that we're doing a good way to go about strengthening our hip-flexors?

Thank you so much!

Yes and yes to a degree. Why are you questioning your coach?

Increasing stride length and frequency, along with foot contact power output increases speed.

Hip flexors are part of the chain, but already developed in most American athletes.

Focusing on the posterior chain (hip flexors are located in front of the body) muscles such as glutes and hamstrings help increase running speed and are lacking in most American youth athletes.

With that said do the V-Ups with everything you have and always listen to your coach.

Thanks for your replies.

I hope my first post did not seem as though I was "doubting" my coach, as I am not; however clearly that impression was portrayed. As I said in my original post, yet in a different context, there can often be things "lost in translation".
What you might be suprised to hear is that I have never had as good of a relationship with any other coach or teacher in my entire life as I have with this coach and the head coach.
I am just the type of person who feels he needs to hear multiple opinions to fully understand a concept that is foreign to me, and I hope I do not come across as obnoxious.

Thank you Mr. Doyle and Maxx not only for your imput but also and most importantly for helping me notice that what I ask harmlessly can potentially be interpreted negatively. The culmination of such seemingly "small" lessons is what eventually builds someone my age into a responsible adult.

Hey no problem--and I didn't want you to think I was chastising you

Like Jon, said, hip flexors are just one part of the whole equation. Personally, v-ups with legs straight are one of my favorite exercises for the abdominals. It takes a lot of strength to do a good number of quality v-ups.