Posted In: Hurdles
Article link:The Key to Fast Sprint Hurdling
Anyone care to take a swing at validating the author’s hypothesis that “The most important aspect of fast spring hurdling is to get the lead leg back to the track as fast as possible” and analyzing the underlying bioemechanics of “The Key to getting the foot of the lead leg back to the track fast is to sweep the opposite arm down from a high position quickly”?
The PDF file has spaces in the link and may cause problems when attempting to download. If you have problems downloading the link above, visit the page at https://www.trackandfieldcoach.ca/track_and_field_coach_2_007.htm and then download the PDF titled “THE KEY TO FAST SPRINT HURDLING”.
Let me know if you still experience problems and I’ll ask permission to post the article elsewhere without the extraneous spaces.
Best,
Christopher
Chistopher – thanks for catching the issue with the blank spaces 🙂
You can also try “copying and pasting the link below…(minus the quotes)
“https://www.trackandfieldcoach.ca/the key to fast sprint hurdling.pdf”
Technology shouldn’t be this hard…
Technology shouldn’t be this hard…
Computers are just a fad; much too hard to ever catch on. 🙂
Best,
Christopher
Call me disappointed…I thought for sure some hurdle coach would take the bait and respond to this article 🙂 I’m assuming that those that read the start of this thread were able to navigate and find their way to cited article/pdf.
I came across this article and Coach Parker’s comprehensive website as a result of a web search. I found this particular article thought provoking and it was my hope that others would as well.
1) In “The Key to Fast Sprint Hurdling” Coach Parker states that “The most important aspect of sprint hurdling is to get the foot of the lead leg back to the track as fast as possible“.
The lead leg landing is an important factor in hurdling and can either inhibit or aid horizontal velocity (the ultimate goal when hurdling). Should it be considered the most important factor (and a focus for both athlete and coach) in fast sprint hurdling as the author suggests?
2 The author continues…”This will reduce the duration of the clearance of the hurdle…”
It’s not uncommon to hear a hurdle coach cue “snapping” or “pushing” the lead leg down. Can the hurdler effectively shorten the amount of time it takes to clear a hurdle by actively trying to get the lead leg down faster?
3) The author states “The Key to getting the foot of the lead leg back to the track fast is to sweep the opposite arm down from a high position quickly. Limbs work in opposition to each other and, since the arm has a smaller mass than the leg, it can be moved faster and ahead of the leg, triggering leg movement”
The author does not indicate how the lead arm would get to this position (a swim like action, driving the lead arm/elbow upward, etc.).
Will sweeping the opposite/lead arm downward effectively reduce the amount of time it takes to return the lead leg(also a downward action)to the ground ?
Is there any negative consequences of a downward sweep of the opposite/lead arm?
4) Coach Parker also notes that while the arm sweep is the key, that “the principle of Conservation of Angular Momentum can be used in which the hurdler raises the torso (upper body) to speed the leg downward (lower body)…the counter clockwise body rotation caused the clockwise rotation of the leg as angular momentum is conserved about the transverse axis of the hurdler“.
Is it possible to “snap” or “push” the lead leg towards the ground without raising the chest/torso?
5) Coach Parker continues “A third skill that helps to return the foot of the lead leg to the track quickly is to drive the foot just about the hurdle crossbar so that the distance to the track surface is minimized“…
Understanding that the hurdler is in an unalterable parabolic flight over the hurdle, can the athlete reduce the flight time/time to return the lead leg to the track, by reducing the distance between the lead leg foot and the hurdle crossbar?
Call me disappointed…I thought for sure some hurdle coach would take the bait and respond to this article 🙂 I’m assuming that those that read the start of this thread were able to navigate and find their way to cited article/pdf.
I came across this article and Coach Parker’s comprehensive website as a result of a web search. I found this particular article thought provoking and it was my hope that others would as well.
1) In “The Key to Fast Sprint Hurdling” Coach Parker states that “[i]The most important aspect of sprint hurdling is to get the foot of the lead leg back to the track as fast as possible[/i]“.
The lead leg landing is an important factor in hurdling and can either inhibit or aid horizontal velocity (the ultimate goal when hurdling). Should it be considered the most important factor (and a focus for both athlete and coach) in fast sprint hurdling as the author suggests?
2 The author continues…”[i]This will reduce the duration of the clearance of the hurdle…[/i]”
It’s not uncommon to hear a hurdle coach cue “snapping” or “pushing” the lead leg down. Can the hurdler effectively shorten the amount of time it takes to clear a hurdle by actively trying to get the lead leg down faster?
3) The author states “[i]The Key to getting the foot of the lead leg back to the track fast is to sweep the opposite arm down from a high position quickly. Limbs work in opposition to each other and, since the arm has a smaller mass than the leg, it can be moved faster and ahead of the leg, triggering leg movement[/i]”
The author does not indicate how the lead arm would get to this position (a swim like action, driving the lead arm/elbow upward, etc.).
Will sweeping the opposite/lead arm downward effectively reduce the amount of time it takes to return the lead leg(also a downward action)to the ground ?
Is there any negative consequences of a downward sweep of the opposite/lead arm?
4) Coach Parker also notes that while the arm sweep is the key, that “[i]the principle of Conservation of Angular Momentum can be used in which the hurdler raises the torso (upper body) to speed the leg downward (lower body)…the counter clockwise body rotation caused the clockwise rotation of the leg as angular momentum is conserved about the transverse axis of the hurdler[/i]“.
Is it possible to “snap” or “push” the lead leg towards the ground without raising the chest/torso?
5) Coach Parker continues “[i]A third skill that helps to return the foot of the lead leg to the track quickly is to drive the foot just about the hurdle crossbar so that the distance to the track surface is minimized[/i]“…
Understanding that the hurdler is in an unalterable parabolic flight over the hurdle, can the athlete reduce the flight time/time to return the lead leg to the track, by reducing the distance between the lead leg foot and the hurdle crossbar?
I meant to get to this when you posted it, but now will have to suffice.
1) I think is kind of stating the obvious. The hurdling action is a modified step, and thus, minimizing flight time is based on the idea that you go from one foot (trail leg) to another foot (lead leg) as fast as possible. As far as it being the most important? I’m not sure, but I probably spend more time on the lead leg than most other hurdle coaches. I think it is important to get athletes (especially beginners) to have a bent leg and I coach this with a series of high knee drills.
2) I don’t think this is the case. How long an athlete stays in the air is directly dependent on how much the center of gravity is elevated. Thus flight time is determined by takeoff, not pushing the leg down. I do think that a quicker lead leg can help take advantage of lower flight angles, however.
3) I’ve never believed in this kind of logic. Maybe it works, but it always seemed dubious to me. My favorite arm action is that of Liu Xiang, though my athletes almost never end up using it.
4) Not without losing balance. 😛
5) I don’t think so. I think a close cutting lead can take advantage of a minimized parabola as stated above. Also, as I stated above, I think the bent lead leg can take advantage of this as well. It would be easier to draw a picture, but I’ll do my best to explain it. If an athlete puts the bottom of their lead leg knee onto a hurdle while their knee is extended, the foot is the same distance from the ground as their knee. Now if they bend their knee their foot is suddenly much closer to the ground than their knee. Not to mention that a bent leg can be ‘snapped’ to the ground much faster than a straight one.
Derrick…
Sometimes I think the hurdle forum on Elitetrack is in need of life support. It seems like unless someone is bashing someone (thankfully Carl continues to stir the pot on the forum in general – mere mortals have fled under less duress), nobody is interested in posting.
Again, I found this article thought provoking. Admittedly, I found it so because I balked at some of the statements Parker makes and I question the underlying biomechanics. I tried to throw it out there without biasing the first time reader.
While I have seen this “overhand” or “overhead” lead arm technique by Merritt and other elite hurdlers (both male and female), I’m also aware that many elite level athletes can get away with technical errors or deviations that lesser athletes can’t overcome.
I was taught (USATF and by others) that the primary role the lead arm plays is to counteract the rotations/torques created by bringing the trail leg alongside the body (outside the COM) during recovery and the hurdle clearance. Ideally it would be swept back in a parallel plane to that of the trail leg. To counter the rotations/torque of the larger mass of the leg (which is kept bent at the knee to create a shorter lever), the lead arm has to open/extend (creating a longer lever) because of its lesser mass as it sweeps back (clockwise) over the trail leg as it’s pulled forward (counter-clockwise). Basic “equal and opposite reaction”. That said – studies show that even this open arm sweep does not completely cancel the rotations induced by the trail leg.
Assuming this is true – then sweeping the arm from overhead downward would seem to be less effective in countering this rotation.
I have a hard time visualizing how the overhead and downward sweep advocated by Parker (a clockwise action when the athlete runs from left to right) will induce an accelerated return of the lead leg/foot to the ground (also a clockwise rotation).
I can’t help but compare this proposed action to the arm sweep used by long jumpers (and TJ’rs) to counter the forward rotations (which were established at take off). But in the case of the long jumpers – this sweep is to decrease the rate of which the feet are rotating/returning to the ground (ie. to keep the feet up longer), the opposite of the goal of the lead leg in a hurdler. Maybe I’m not seeing something here.
I do agree that the torso has to become upright as part of the lead leg landing process. The timing of this and the rate at which it happens are factors.
In regards to the third skill proposed by Parker – driving the foot just above the crossbar – I’m once again not sure I agree completely. I think this is a result of the hurdle takeoff/attack angle – where the amplitude and duration of the parabolic flight over the hurdle is established. If the flight is low/flat – then the hurdle clearance is minimized (assuming proper flight posture). If the resultant flight is high – then lowering the lead leg/foot in flight to minimize hurdle clearance seems cosmetic at best as the COM is still traveling in a high, unalterable, parabolic path. I don’t think the hurdler is coming down any sooner than Sir Isaac says so 🙂
Apologies to Coach Parker, I’m sure he would disagree with my thoughts and observations. Just a chance to share an article to stimulate the mind and to encourage dialog on the forum.
Hopefully someone will issue a counterpoint or clear up any misunderstandings.
Couple of points –
I disagree with the “snap” of the lead leg theory. As RCfan2 and Physics tells us that all flights will be parabolic based off of our take-off speed and angle. After that, it is up to gravity to bring us back to the earth. Teach athletes to “run off” the hurdle and you will find a much better effect. The closer we can get to mimicking running off the hurdle, the better. All arm and leg movements are consequently in sync to 1) clear the hurdle and 2) maintain balance.
The counter-movement of the lead arm coming downward in conjunction with the lead leg is seen among elite male hurdlers. The rationale for the high lead arm sweeping down, is that the lower leg is sweeping upward at that moment. Therefore they are counteracting each other, yet the lower has much greater mass at a distal point (the foot) so the hurdler must lean into the hurdle in order to avoid backward rotation. Otherwise the mass of the lower leg v. the mass of the arm is not a fair fight. With men, I teach the arm sweep down, with women, the movement is unnecessary because the hurdle is below the line of the inseam. They don’t have to raise the leg as high and can control rotation much easier with just the torso.
The majority of backward rotation is still controlled by the torso. I believe that raising the arm, raises the athlete’s COM just before the hurdle. Whether this shortens the parabolic flight or feels like it does still needs to be clarified, unless someone has data to show. Ralph Mann’s books describes the arm action to be the overhead movement, so there must be some merit to it.
As far as boiling hurdling down to the lead arm sweeping downward, I would say there are too many other factors in play. Maybe for a hurdler that did everything else 100% correctly and then changed up the lead arm slightly might gain an advantage. I always fear the novice coach reading articles like this and thinking this is like finding gold. Tom Tellez has a podcast about hurdling on athletics coaching that I have listened to many times. Anything I say is probably just being parroted back from listening to that talk.
“Run off the hurdle” is his classic line and I will use it till the day I perish.
I disagree with the “snap” of the lead leg theory. As RCfan2 and Physics tells us that all flights will be parabolic based off of our take-off speed and angle. After that, it is up to gravity to bring us back to the earth.
I’m on the road and I have not had an opportunity to read the paper nor the details of this thread, so apologies in advance if I’m missing the thrust of this thread, but I’ve seen several references to Newtonian mechanics and I think there *may* be confusion about Newtonian mechanics of a solid body and a non-rigid body. Yes, it is true that the COM of both have a parabolic flight, and ignoring air resistance, we can predict where an apple on a parabolic flight will contact the track, but such a prediction can not be made for a non-rigid body without knowing what the non-rigid body does during flight. If the athlete keeps the torso bent low after the clearing the hurdle, it is possible to stay in flight farther down the track and the foot contact can be delayed. This does not violate Newtonian mechanics, as the COM for a non-rigid body is the sum of all the parts. If the upper body parts are kept lower, then the lower body parts are kept higher (and vice versa) so that the sum of all these parts (COM) observe remains on a parabolic flight (ignoring wind effects). In other words, there is more than gravity that determines where the foot will contact.
Hope that is helpful.
Best,
Christopher
Chad & Chris,
Thanks for your sharing your thoughts on this topic…
Here’s another link that I think you both might find interesting on this topic – an article by Craig McDonald:
The Angular Momentum of Hurdle Clearance
Chris…
I understand that in a non-rigid body that the COM is not fixed (see the high jump arch for another example). And I completely agree that the body can be positioned, by maintaining forward lean (or by counter rotations of the arms), to delay the landing of the lead leg. However, all that you’re doing is allowing the COM to continue dropping – the parabolic path would seem to remain intact and unaltered. It goes without saying that this delay would result in a multitude of negative consequences for the hurdler 🙂
Parker is talking about elite athletes and what “the key to fast sprint hurdling is” – which he claims is the overhead and downward action of the lead arm, intentionally reducing the hurdle clearance of the lead leg foot in flight, etc. Its probably safe to assume that Merritt, Richardson and others are already landing in technically correct body positions/postures. For an elite to get back to the ground sooner, the parabolic path itself would seem to have to be altered. It may be possible to increase the angular velocity of the lead leg, so that it is moving more rapidly towards the ground (creating negative foot speed), but I think the lead leg foot can only reach the ground after the hurdler’s COM has descended enough on the downward slope of the parabolic flight. This would seem dependent on how low and flat the parabolic flight is and not so much on the angular velocity of the lead leg. I think a slower lead leg, but correctly timed descent of the lead leg would touch down in the same place… Maybe I’m missing something here.
Yes, if the hurdler is landing with the lead leg foot far in front of their COM (huge braking action), and their lead leg is yielding excessively (lowering the COM), etc. – then there are issues to resolve regarding timing of raising the torso, the height/duration of the parabolic flight (one can expect a big landing impact if the flight is high), angular momentum on the transverse axis, etc.
So while the COM is in an unalterable parabolic flight over the hurdle in a non-rigid body, it’s possible to reposition limbs, etc. to effect rotations and clearance of the body segments over the hurdle. That said – I do not believe you can artificially reduce the flight time of COM over the hurdle by “snapping down the lead leg”, nor by “sweeping the opposite arm down”, nor by artificially reducing the clearance between the lead leg foot and the hurdle crossbar in flight. If the COM is in a high parabolic flight, I don’t think you’re coming down until Sir Isaac says so.. I suppose you could plantar flex the foot as well to try to get the toes to the track a fraction sooner – but obviously this has consequences as well.
I guess I think of age group hurdlers who “post” their takeoff foot far out in front of the COM during take off and are lofted into a high parabolic flight over the hurdle. No amount of driving down the lead arm or whatever is going to bring them back to earth any sooner than gravity dictates. And if they fail to counteract the angular momentum (on the vertical axis) created by bring the trail leg through, we can expect them to have to resolve this rotation at and/or after landing (lead leg drift, twisted and off balance landings, etc.).
What I’m trying to say is that you can stay on the parabolic flight as long as you want (or until you hit the ground), but you can’t get off early 🙂
I think some coaches and athletes think that by lowering the torso (ie. bending at the waist) “during” the flight over the hurdle lowers their center of mass and therefor reduces the flight time. In actuality it’s allowing the COM to be in a lower flight (which was pre-established at toe off of the take off) over the hurdle – and to still clear the hurdle for the reasons you noted – that in an action/reaction it brings the lower body upward. If that makes sense.
All that said, one would think that a rapidly descending lead leg, with a foot landing under (or possibly slightly behind) the COM, could reduce braking actions (think negative foot speed), allowing for greater horizontal velocity off the hurdle. Not sure swinging the opposing lead arm down in the same direction as the lead leg is going to induce this. I have heard that some coaches believe that a deep forward lean of the torso will create a stretch reflex in the hip extensors – helping accelerate the lead leg toward the ground when the torso is raised.
Still…fun stuff to think about and slosh about in our brains…
I understand that in a non-rigid body that the COM is not fixed (see the high jump arch for another example).
OK, I think we agree on these points: 1) once in flight, the COM follows a parabolic trajectory, and 2) the COM is not fixed with respect to any reference point on an athlete’s body (e.g. the navel).
And I completely agree that the body can be positioned, by maintaining forward lean (or by counter rotations of the arms), to delay the landing of the lead leg. However, all that you’re doing is allowing the COM to continue dropping – the parabolic path would seem to remain intact and unaltered. It goes without saying that this delay would result in a multitude of negative consequences for the hurdler 🙂
Of course, the ultimate goal of this discussion is to understand the mechanics of the hurdles, but if I understand your questions and assertions regarding the PDF, I think you may be confused by the physics, so I think it’s helpful to separate those for a moment and focus on the physics. Yes, this or that example of a body position may be detrimental to efficient hurdle performance, but it can advance the discussion by understanding what is possible without violating Newtonian mechanics. And, since you agree that there are things an athlete can do to delay contact with the track without violating the laws of physics, then conversely, there are things the athlete can do to get to the track sooner without violating these laws.
For an elite to get back to the ground sooner, the parabolic path itself would seem to have to be altered. It may be possible to increase the angular velocity of the lead leg, so that it is moving more rapidly towards the ground (creating negative foot speed), but I think the lead leg foot can only reach the ground after the hurdler’s COM has descended enough on the downward slope of the parabolic flight.
While there certainly are limits on where the foot can be with respect to the COM (e.g. a six foot athlete can not get taller during flight and therefore there is a limit on how far a foot can be from the COM), the COM is a function of all the parts, and therefore if some of the body parts (e.g. torso and trail leg) are relatively high in reference to the COM, then the lead leg can extend low in reference to the COM, and this can happen while the COM remains on a parabolic path.
Or, have I completely misunderstood your question?
Best,
Christopher
Currently Ron Parker is my coach is there any questions you guys would like to ask him? We only have one hurdler in our group right now and that’s not me so I have no idea! I’ll get some feedback as to what he says about your responses. All the best!
And, since you agree that there are things an athlete can do to delay contact with the track without violating the laws of physics, then conversely, there are things the athlete can do to get to the track sooner without violating these laws.
No, I guess I don’t completely agree that conversely that a hurdler can get back to the track sooner than the path of the COM and gravity dictates. Again, we’re talking about a parabolic flight over the hurdle. This is an arc with a both rising and descending sides (somewhere over the hurdle rainbow).
My point, which obviously I’m making poorly is that the COM has to fall far enough on the descending side of the parabolic flight before a given athlete can touch the ground. From that point on, yes the athlete can take certain actions to delay the touchdown – up to the point where the center of mass is so low they crash into the track.
Its also my understanding that all values of angular momentum in the system are also per-established at takeoff – and like the parabolic flight path – unalterable (excluding outside influences such as wind, etc) during flight.
While you can delay the amount of time from ground take off to touchdown and still honor Newton by manipulating the body parts and by countering forward rotations until inevitably you crash into the track (again the parabola remains unaltered – your just allowing the COM to fall further on the descending slope), I don’t believe you can manipulate your body parts or rotations to get back to the ground any sooner than your anthropometric’s and the parabolic flight of the COM dictates. Driving your lead arm downward is not going to aid gravity and draw you back to mother earth any sooner.
Parker asserts that driving the lead arm from overhead downward will cause the lead leg to descend faster, reducing the hurdle clearance time. And of course, he’s using elite hurdlers as his example. And if its descending faster, and therefor sooner, then the hurdle landing/touchdown would have to be closer to the hurdle.
My contention is – even if the hurdler were to get the lead leg fully extended under the COM sooner (and still somehow manage to clear the hurdle board), with the hurdler in a full upright posture (and hurdlers will have some forward lean) sooner, and foot totally plantar flexed (making the athlete as tall as possible on his tippy-toes) – he’s not going to touch the ground any sooner than gravity dictates. Simply his COM has to descend far enough on this parabolic flight until he can reach the ground. In contrast, a hurdler could continue to lean forward & bent at the waist, and I suppose could even swing his arms through (as if a long jumper) to counter his forward rotation, to delay the hurdle landing until he crashes into the track.
Yes, if there are gross technical errors, where the hurdler lands with his lead foot far out in front of his COM or heaven forbid, leaning backwards (insufficient angular momentum) – then correcting these errors will indeed reduce the hurdle clearance flight time. But again, Parker is talking elites who are not landing in such a posture.
It would seem that based on anthropometrics, hurdle height & the parabolic flight, there are practical limits to where the lead leg foot can land in relation to the hurdle itself. In other words, it’s unlikely that an elite male hurdler could land say within a foot of the hurdle – no matter how fast he drives his lead arm down (which I don’t think will has a positive effect on the angular velocity of the lead leg). Are we sure that the hurdlers COM is low enough at 1 foot past the hurdle for the hurdler to touch the ground, even if fully upright, even with maximal plantar flexion?
I suppose it would be interesting to discover how effective/efficient elite hurdlers are in regards to lead leg touch down. Are they “late” in getting it down, allowing the COM to descend further than optimal?
Its notable that the lead leg is descending in the same direction as the lead arm action as suggested by Parker (both clockwise actions if the athletes is running from left to right). This is the same arm action that long jumpers use to counter forward rotations (which are present in the hurdler as well) to DELAY the legs descent towards the ground. Parker seems to be proposing a similar action to do precisely the opposite – to ACCELERATE the lead leg towards the ground.
Did you get a chance to look at the article by Craig McDonald regarding angular momentum in hurdling (see previous post)?
Article is nonsense with relation to science. Snapping the lead leg down too quickly if even at all possible and I am not sure it is, would probably create excessive rotational forces at the ankle and a longer contact time in the next few steps. The idea of snapping the leg down is too prevent the problem of a collapsing COM on ground contact over the hurdle with hurdlers who are slow at getting their legs down and look like ballerinas instead of hurdlers. I am not against the snapping cue, but I would not use it for the purpose the article supposes is the key faster hurdling when every picture shown by shows it is the stepping through with the trail leg as the ending characteristic in elite hurdling.
I look at hurdle progression as a 4 step process, attacking, striding, snapping, and stepping. It’s not linear, but you can’t do 4th step in the process without doing the 3rd, and the 3rd with out doing the 2nd, and the 2nd without doing the 1st and if you are not doing the 1st you are likely walking or literally jumping over the hurdles. One can say that stepping through with the trail leg will cause the lead leg to come down and this is true, but it doesn’t stop the ballerina action. Sometimes everything comes naturally when the athlete starts attacking the hurdle, but sometimes there is a block in the process like with girl athletes who dance tend to want to be graceful and artistic over the hurdles. The important part is knowing when to cue which step in the process and how to set it up for the athlete to succeed. You can’t cue striding out at take off when the athlete is too close to the hurdle and you can’t cue step over when the athlete wants to be graceful instead of fast and powerful.