Sprinting: a push or a pull?

Posted In: Polls

  • Mike Young
    Keymaster
    Mike Young on #8280

    Do you think the propulsive mechanism in maximum velocity sprinting is more of a push (where knee extensors are primarily responsible for force) or a pull (where leg extensors are primarily responsible for force)?

    ELITETRACK Founder

    Avatar
    Participant
    daa20 on #19039

    I think its both, it all depends upon how you look at it. If you have taken a physics course you know that its a pull but logically its a push. The reason its a pull is because you are trying to pull your leg forward but the frictional force is acting in the opposite direction. It is also a push because logically you are pushing off your feet and toes applying a force to the ground and it applies a normal force (as its called in physics) on you pushing you in the opposite direction you applied the force (every action has an equal but opposite reaction). 🙂

    Avatar
    Participant
    2belite on #19040

    I think the better you get the more it moves towards a push.

    Mike Young
    Keymaster
    Mike Young on #19041

    Daa-
    I'm not following what you're saying here, please explain:

    [i]Originally posted by Daa20[/i]
    If you have taken a physics course you know that its a pull but logically its a push. The reason its a pull is because you are trying to pull your leg forward but the frictional force is acting in the opposite direction.

    ELITETRACK Founder

    Avatar
    Participant
    daa20 on #19042

    Its very hard to explain and very confusing because there are so many levers (your muscles) involved. I cant really explain it, I'll get confused, just disregard that part of the answer if you have to.

    Carl Valle
    Participant
    Carl Valle on #19043

    The action of the movement is a push, muscles are pulling the levers, but any efforts of pulling back is a injury waiting to happen.

    Avatar
    Participant
    QUIKAZHELL on #19044

    phoenix,
    is that link,, http://www.regenerationlab.com your new site? when will it be up?

    Avatar
    Participant
    2belite on #19045

    There will always be some pull when sprinting because the foot touches down infront the com.

    Avatar
    Participant
    jjh999 on #19046

    There will always be some pull when sprinting because the foot touches down infront the com.

    True, the touchdown occurs slightly ahead of COM, but don't forget about momentum…the COM will still be moving forward at touchdown…Proper sprint technique at touchdown involves the stabilzation of the COM over the touchdown foot (amortization phase, hopefully as short as possible) followed by the forceful extension of the hip via the hamstrings in order to project the COM "up and forward" to maintain the forward motion.

    (note: my comment refers to maximum velocity, not acceleration)

    I think it's a pushing action. I'm not too dogmatic on most stuff, but any cue about pulling or clawing is bad news IMHO…

    😉

    Avatar
    Participant
    Kebba Tolbert on #19047

    [i]Originally posted by JJ[/i]
    [quote]
    I think it's a pushing action. I'm not too dogmatic on most stuff, but any cue about pulling or clawing is bad news IMHO…

    😉

    ok… i'll play devil's advocate here…. why is the cue bad news if it gets the athlete to do what **you** want. i mean i tell kids who overstride to "be quick at the end" all the time. maybe they just don't feel it as a "push" but as a pull w/a certain part of their body…

    Avatar
    Participant
    jjh999 on #19048

    Ok, Mr. Devil, errr Satan, errr Mephistopheles…

    You know why I don't use the pull cues…take a look at one of your Tellez "lecture tapes"…

    Seriously, though, I don't use any cues involving pulling, b/c so many of the kids that come to me at the DIII level have already mastered that skill unfortunately… Still too many coaches teaching them to drive their knees high and reach out with their strides…I spend the majority of my time during an athlete's first year with me fixing that…

    Carl Valle
    Participant
    Carl Valle on #19049

    I think what we are debating is the physical actions of the body, not perceptions of the athlete. Like what Kebba said earlier, any drill that helps the athlete do the right thing might be good…..my question is when this cue ages does it cause harm later on. If someone stops overstriding and then starts to actually pull back after progressing then the cues should be changed to something even more subtle, then perhaps all cues would be dropped when at WC level.

    Quick,

    My site should be up in a few weeks. It is not going to be another forum, it will be just a blog site with great products, articles, interviews with world class experts in sports training, and reviews. I wish to thank Mike for his understanding with my shameless act of self promotion!

    Avatar
    Participant
    2belite on #19050

    "To minimize the touchdown distance, and get the most out of this action, the sprinter must be very strong in the hamstrings and gluteal muscle since these are needed to pull the body over the touchdown point during the initial portion of ground contact. More than any other factor the strength of these muscles dictate the success of a sprinter. Pulling the body over the touchdown leg in the first 20-30% of ground contact is the only way to produce the needed vertical forces economicaly"( Ralph Mann)

    Thoughts?

    Avatar
    Participant
    sub40 on #19051

    this might take the conversation in a different direction …but….
    I would second the comment about being ahead of the COM and pulling back, and I would add that if you look at most muscle strains that occur….its at the hamstring…which come  from the extension of the hip, not the flexion of the knee.  So I feel that more time should be spent on strengthening the hamstrings this way.  Its more applicable to the training and technique of the sprints

    the first few steps in the hundred however should be seen as push…..as they are more piston like…..once you get rotary….its a pull.

    Avatar
    Participant
    flow on #19052

    once you get rotary….its a pull

    at first id agree,  but at maxV the the power applied is vertical,  not horizontal  (if i aint mixing things up here!?),  as mike writes in the FAQs  or classics,  dunno.   so landing in front of the com,  the leg is being mostly pulled back by the  gluteus etc.(=hip extensors?= pull),  then it goes over into a push as you straighten  the leg,  however not to push yourself forward.   the push being behind the com at this point is just an adaption to the high speed.  probably the most interesting phase here is the part right under the com which gives you the most vertical thrust to create more hang time.
    so its the  phase under the com being relevant,  and if thats equal to the transitional phase between push and pull (which i dont know) we have a combination of the two being important for maxv running.  the pull however being the initiator of the movement up to this point should  be more releveant,   as the push phase is  gradually loosing its ability for upward thrust going behind the com.

Viewing 15 posts - 1 through 15 (of 31 total)
  • You must be logged in to reply to this topic.