Front mechanics

I hear the term used often, would any one care to share how to achieve it.

I have sent a pm to a couple of members so I will ask at this time they do not share what I said in the pm’s.

[LEFT] egoscue_4loadpoints_side_250x358v2.jpgIf you take the mid-line of your body in sagittal view, everything that happens in front both in air and on ground is Front Mechanics. Everything in back of mid-line on the ground and in the air is backside mechanics. The less time your leg spends in backside mechanics, the better your frontside mechanics will be. Ralph Mann writes that if you can reduce 10 degrees of backside upper leg travel, 10 degrees of front-side upper leg travel will occur…aka high knees, better frontside, etc. The main reason fast people let their leg move into backside mechanics is so there will be a stretch put on the hip-flexor that will immediately snap the upper leg back into front mechanics and create a better situation for applying force back into the ground. The slower the pace of the race, the less frontside will be needed to run race efficiently. Fast sprinting requires short ground contact times which require better front mechanics…slower pace running requires longer ground contact times which need less high knee front mechanics. All of this is related to pelvis stability, posture, correct oscillations, etc. which can get into a big presentation of information that I won’t get into here. For the 35K foot view of front mechanics, the less time spent in backside mechanics, the better opportunity to achieve good frontside mechanics. The more time spent in backside mechanics, the less opportunity to achieve good front mechanics. [/LEFT]

6a010535f94817970b01156fba431e970c-800wi.v2.jpg Frontside and backside is related to mid-line, or long axis of the body. So when the long axis of body changes angles, front side and backside go with it. The time when most athletes wreck their front mechanics is when they are in drive phase and transitioning from drive phase to high speed running. If foot and leg get caught too long in backside mechanics during drive and transition, they will remain too much in backside mechanics when arriving in high speed running posture. I would include excessive knee flexion during first 10-12 steps of drive phase as getting too much backside. Disciplined front mechanics the first part(s) of the race will create a situation to remain in good front mechanics for sprinting later in a race. There is an old saying about racing, ‘once you lose your hips, you’ll never get them back’…and this is true for long races, short races, and field event runways. I’d suggest that you could substitute this saying, ‘once you get too deep into backside mechanics, you’ll never get a good front mechanics back’.

Frontside mechanics is also used to refer to people whose legs seem to be in front of the person more than they are behind the person. This results in avoiding the foot sweeping up to the butt (see slow motion of Asafa for this) and a very fast forward thrust with the trailing leg.

How to achieve? Excellent abdominal strength helping posterior pelvic tilt, and naturally (not forced) powerful ground contacts.

Your use of the word ‘REQUIRES’ is troubling to me here. GCT is a RESULT of sprinting speed, not the cause of it. The notion that shorter GCT is something to persue makes no sense, because the shorter GCTs that result from higher speeds are the primary obstacle to even faster speeds. Less time on the ground to input forces. Longer GCTs would actually be beneficial and allow sprinters to input greater forces, but sprinters are limited by the mechanics of human sprinting. As Weyland pointed out, one of the primary advantages four legged animals, which are generally faster than two legged animals, have is that they are in contact with the ground much more. Total GCT is much higher with 4 legs rather than 2. Shorter GCTs are not a good thing when it comes to sprinting, they are the primary obstacle sprinters must overcome.

Oh man…look at how much typing you made me do.

I also use the word “longer”, not long. You are referring to a study (Weyland’s) about how pulling weighted sleds effect high speed running mechanics, correct? In resisted running, as in starting, it is beneficial (some might say a requirement) to spend more time on the ground in order to apply more force for overcoming resistance…I agree with that statement. Just as when an American football running back needs to drive his way through a linebacker, he needs to spend more time on the ground to do that. Running through a linebacker doesn’t have a whole bunch to do with high speed sprinting. There is also quite a bit of disagreement out there in athletics community as to whether his weighted sled pull study is even applicable to the actual biomechanics of max velocity sprinting…at all. The stronger your drive phase the more momentum you will have for your max velocity running…this is obvious. Good for specifically training the max velocity biomechanics…no. My opinion is that Weyland’s sled pull study does not have much to do with max velocity sprinting…block starts and drive phase, absolutely. There is an obvious optimal balance of force application and frequency in max velocity sprinting. My comment assumed that this was understood. To dispute small GCTs in max velocity mechanics with data from a weighted sled pull study is disturbing to me…if I can borrow your word. As to Weyland’s other point you mention, I don’t coach any four legged animals so I haven’t done any research on what makes them fast. I have studied Ralph Mann who has done a ton of research over the last couple of decades on what makes two-legged humans fast, and his research shows that a “critical general performance descriptor for the short sprints at maximum velocity” is that the fastest folks spend less time on the ground than the slower folks…while running fast. The fastest are able to apply the most force in the shortest amount of time. Now of course, if those same fast folks reduce their ground times too much, they will not be able to apply enough force to run their fastest. Again, there is obviously a relationship between the two that is optimal. I’ve heard Tellez, Pfaff, Bosch, Mann, Seagrave, Winkler…the list goes on, all talk about reducing ground contact times in sprinting. I’ve seen Pfaff, Bosch, Seagrave and Winkler all put athletes through training that is specifically designed to create these short GCTs. Rudiment jumps are the most commonly known method. Pursuing short GCTs, which you say makes “no sense”, seems to make plenty of sense to all of these world class coaches. I’m hopeful you’ve heard of a few of them.

As it relates to slower pace races, an elite sprinter touches his foot down 6-8 inches in front of COG at top speeds. Mann says that the fastest people do 85% of their force application during those first 6-8 inches before the foot arrives directly under COG. This creates a shorter GCT than any of the longer distance races. Long sprinters contact the ground further out in front of their COG, as much as 20% further. Add over and inch of distance to support phase and a slower 100m pace and GCTs have to become longer and less dynamic to save energy in order to complete the race. If a 400m runner tried to run with 100m pace GCTs, the athlete would run too fast of a split for first 200 then tie up and fall apart before 250m…limp across finish lines constantly. As for slower paced races, like 800m through marathon. It is silly to think that an athlete in the 10K would contact ground at same distance from COG as sprinter and be able to apply 85% of force app in those first 6-8 inches they are on ground. The GCT/flight time ration can not remain the same at slower paces. I don’t know exact data for this but my guess is that a 10K to marathon type athlete’s force application distribution might be inverse of 100m elite, and apply 15% of effort in front-side ground mechanics, 85% in backside ground mechanic. Watch slo-mo film of any long distance athlete and this will be evident. This would create more time on ground behind the body as well. I have heard Tellez talk about this optimal GCT relationship between the race paces several times. Actually, the turn of phrase that is “troubling” you is actually borrowed from his explanation of Seb Coe’s mechanics when running 1/4-mile races. The context is Coe running faster training races (in relays) versus a short sprinter moving up to ¼-mile race. Tellez describes how each strives to adjust GCT in relation to the rhythms they are used to at their preferred race distances. There is a lot of footage on the web of Bolt running 400m races where you can see that the emphasis of his force application happens later in his support/stance phase versus where his force application emphasis is occurring in his 9.58…which there is also a lot of footage of out there…Universal has best version in my opinion.

To sum up, yes…if you are running short sprint races while pulling a weighted sled, then yes…it would benefit you to spend a little more time on the ground to apply force while trying to run your fastest in that context. If you are racing short sprint races with only your own body weight then it would benefit you to spend very short periods of time on the ground… for men no more than .087 seconds and women no more than .083 seconds, at elite levels. Those numbers are straight out of Mann’s last publication. Google “Neuro-Biomechanics of Maximum Velocity Sprinting” co-authored by Seagrave. It is a good place to begin researching max velocity running mechanics (he mentions elite level GCTs). Also, I have not been able to teach my athletes how to have four legs. Let me know of your successes coaching your four legged athletes. I understand that they are not limited by human sprint mechanics.

Hey guy with three posts on this site- how about showing a little more courtesy and respect when you address other members here? Leave the sarcasm at the door.

T-Slow, thanks…point taken. In general, I tend to fight fire with fire…or maybe I was responding to condescension with sarcasm. Maybe I had received condescending tone from star61 because of so few posts on my part. I live this stuff even if I just found a few weeks ago. Besides sarcasm, is rest of my post solid for you? I seek most honest opinion.

You shouldn’t have wasted your time. There are a few simple facts that are indisputable. One is, the only thing propelling an athlete forward is the force he generates while in contact with the ground. Two, he can only generate that force when he is in contact with the ground. I’m not advocating trying to INCREASE contact time, but it is just as silly to advocate trying to reduce GCT just to reduce it. And don’t confuse the need for sprinters to develop the ability to generate more force in the short GCT that sprinting offers (improving RFD), especially at max v, with attempts to terminate GCT early. Reducing GCT means you are operating farther to the left on the force time curve…where very little force can be generated because of the very short times. How does reducing that time, which by definition then reduces the force input, make you go faster? There are a lot of great coaches out there that have no true understanding of physics, and a lot who think correlation = causation. It just ain’t so, no matter how many words you type. Its about increasing the force input during the available GCT. Reducing the GCT does not increase your ability to input greater forces, it reduces it. Again, ever shortening GCTs with increasing speed is the impediment to higher speeds in the first place, why on earth would you do something to reduce GCT even further when it does nothing to improve your ability to input forces? The focus should be on training that improves the sprinter’s ability to input greater force during GCT, which, as GCT becomes ever shorter with increasing velocity, should focus on RFD.

In short GCT is shorter for elites as they are able to (through increased rfd) move through there rom during GT faster

There is no attempt to be quick footed, it is a by product of the efficient force applied.

Good post star :slight_smile:

No offense was taken on my part and I meant none, just a little smart a$$ in me. I like empassioned, well thought out posts, even if I disagree. Its how we learn. As long as there is no name calling or derogatory attacks, its all good fun. Looking forward to your replies.

No question that the internet is full of fight-fire-with-fire; what’s great about here is that even if things get a little heated from time to time, people cool off and the ideas tend to be at the forefront, not personality or ego. It’s great to have another experienced, intelligent member here to learn from! I look forward to reading more of your posts.

Star, I appreciate a little smart arse in folks as well…prolly why I enjoy dropping a little sarcasm here and there myself. I also enjoy impassioned, smart, well researched debate. It is how we evolve in just about everything…academics, politics…and track and field. If everyone agreed about everything the world would be a very dull place.

I just assumed it was Weyland’s sled pull study you were referring to. Thanks for the link. I would still hesitate to put too much stock in research done on a treadmill. Bosch disputes any biomechanical data done on a treadmill, unless the data is meant to prove some point specifically about treadmill running. The ground is moving for you, the hip and leg anatomy do not work in same biomechanic, the stance mechanic is not specific to sprinting over stable surface and force applications are different…again, mostly because ground is moving for you. Hamstrings don’t have to do much on a treadmill. Furthermore, Weyland tells you up front that he has only worked with 30 or so subjects of varying sprint abilities. First off, that is not a big enough sample group for me to put much trust into his data and findings. Secondly, I couldn’t tell you if any of his subjects have ever run under 11 seconds in the 100m. Unskilled runner’s data on a treadmill is not specific enough to compare to elite sprinters running over solid ground…for me at least.

I will again defer to Ralph Mann, who has done the most extensive research on nothing but elite level sprinters and hurdlers (has to be over thousand by now, maybe couple thousand) over the last few decades or so. He has biomechanically analyzed every, yes every, elite American sprinter and hurdler since 1982. I believe he has been publishing his research data and findings since 1984. His latest and best publication was this year, 2011. It is fantastic (as they all have been) and I’d suggest it to anyone who coaches runners. You can find it on Amazon. His nearly 3 decades of research says that the best male sprinters in the world spend 0.087 seconds or less, while poor sprinters spend 0.101 seconds or more. Ton of data on Women as well. His good and poor evaluations are relative to thousands of elite sprinters running actual races, not 33 poor schlubs pulled off the local track and put on a treadmill. Mann’s good sprinters run approximately 10 sec or less, while his athletes from the poor category are still making NCAA finals. Again, I think it is obvious if a 10 sec or less guy tried to quicken GCT to 0.050 sec or less, he would obviously not be able to apply enough force needed to run his fastest. That is absolutely not what I am trying to suggest in my previous posts. My original statement says “short” contact times for fast, and “longer” for slower…not shortest and/or longest. I use these words in context to what I understand Mann to have already figured out. I do not suggest that to run fast you have to shorten GCTs to ridiculous levels. There is obviously tremendous power outputs by very strong athletes inside of the 0.087 GCTs I am referring to as “short”…in these posts. “Longer” is spelled out in the numbers I’ve already quoted. As for my use of the word longer for slower pace racing, please see Mann’s chapter on what elite level quarter milers from the past 3 decades do while they are on the ground. I feel like the folks who continue to debate that I say the absolute shortest GCT would make for the fastest run have not read my entire, long-winded posts…or jumped to conclusion on my original post.

Many track coaches do misunderstand biomechanics quite a bit, I definitely agree whole-heatedly with that statement…but none of the ones I name dropped in my last post misunderstand biomechanics. I will have to stop carrying on now…my wife is beginning to get mad at me. Until next time…peace.

I hadn’t been to a message board in some time. When I saw this one I got excited for potential of learning and sharing on here. I did forget how easy it is to get caught up in the anonymity of a message board. I look forward to future discussions as well.

Mann’s data indicate that the fastest sprinters have the shortest GCTs, I think that should be obvious. ANY sprinter will reduce his/her GCT by simply sprinting faster. Weyland et. al. have also measured the travel that the body does during GCT, and it does not change with speed. Meaning, GCT initiates at about the same place relative to COG and terminates some microsecs later at a position relative relative to COG. The position of GCT at termination relative to COG doesn’t deviate, meaning there is no early termination of GCT at faster speeds. Secondly, early termination would only be of benefit if it enabled the next stride to start sooner, i.e., higher frequency. Many studies have shown that the distinction between elite and non-elite sprinters is not frequency.

GCT is only shorter because the COG is travelling faster through that range of motion. This is a simple, but very important, disctinction, so I’ll state its significance to training again. Shorter GCTs are a result of faster sprinting, not the cause. Therefore focused training to simply reduce GCT for the sake of reducing GCT is a fruitless persuit. Train to increase force applied during GCT, and the rate at which that force is produced, should be the focus, and higher speeds, along the shorter GCTs, will follow.

This thread has been high-jacked by the discussion of GCTs. It was originally athread about “front” mechanics. My initial point was that fastsprinting folks are front side monsters. They do not exist in backsidemechanic like slower paced racing athletes. This greater front-sidemechanic running naturally results in a greater force application into theground…obvious. It is a natural result of dropping anything from agreater distance from above the ground…or another analogy you hear a lot is ahammer that is brought back further. A sprinter who begins with greatfrontside mechanics, is running efficiently and faster than everyone else inthe race, will have shorter ground contact times than everyone else in therace. The moment that sprinter over-applies force into the ground, pushesinto the ground too long, or in a slightly incorrect direction…well, thenthere goes the great frontside mechanic, and full potential for that sprinteffort.

Sprinting fast is aformula of stride length (force application) and stride rate (ground contacttimes). If everything else is solid in the running technique, then thecloser that male athlete can get to 0.085 sec for GCT, the better. Running is by nature a cyclical action, so everything that happenseffects everything else that happens thereafter. Great frontside runningresults in near full leg/hip extensions at or before ground contact, and jointflexion occurs earlier in the backside mechanic. Frontside is not justabout how high you can get your knee in front of you, but more about setting upan early and tall hip/leg extension for GC. This is where and when the force is applied. In slower pace running the leg and hip don’treach extension until later in support phase, and near end of backside groundcontact. The leg strikes with moreflexion, then re-pushes later. Where this extension occurs (literally thetiming of it) in the different paces will largely determine the GCT. Theearlier the extension, the shorter the GCT (fastest folks are near fullextension 4-6 inches before they strike ground). The later the leg/hipextension occurs, the later and less the force application, thus the longerthat athlete has been on the ground.

There is a greatvideo on the Canadian Athletics Coaches Centre website of Dan Pfaff explainingwhy Donavan Bailey lost a particular race to Mo Green. You watch the racein super-slow motion while Pfaff explains over top of video that Baileyover-pushes the ground for only two strides at somewhere around 50-60m, andthis is why he looses the race. Pfaff was Bailey’s coach at the time ofthe race, and also while he was the world record holder and the time he wasbest in the world. Bailey’s GCTs last too long for only two steps andGreen is gone (Bailey pushes the broken treadmill). There is a greatvideo on Youtube of Bolt in a race, super slow-mo from the side as the cameratravels at the same speed as the athletes. Bolt over-pushes the groundearly in the race, and is losing early. You can see his leg extensionoccurs behind him. He catches up and wins the race, and you can literallysee him in the video bring the timing of his leg extension back in front andunder him as he runs down the guy in lane 8/9. Early in the race the guyin outside lane is phenomenal. These are both easily accessible videos. There are other races on Youtube of Bolt running 400m races and whenslowed down, you can see the ground mechanic differences between these and hisfaster 100m races. Please feel free to Dartfish the GCT of these vidsyourself. They are obviously not perfect because of potential frame ratedifferences in all digital means used, but you’ll get the picture.

Please understandthat I am not trying to re-hijack this thread with leg extension talk, butunderstand that this is a part of great frontside mechanics (that beinganything that happens in front of the saggital COM mid-line of the body). Hopefully I’ve made clear that this all has a direct relationship withforce application and contact times. If you are doing nothing in trainingbut spending time applying force for longer periods of time, then you areeither running backside and slower than your full potential, of you aretraining throwers…and even then force application has a critical relationshipwith speed.

You make a tremedous number of assumptions that don’t actually meet up with scientific observations. For example, you again talk about faster sprinters having shorter GCTs because of some mechanical difference in their form…it just isn’t so. Faster sprinters have shorter GCTs because they are running faster. If you have data or film, look at GCTs of sprinters of different caliber when running at the same speed. You will find scatter with little correlation. I don’t mean to be an arse, but long winded diatribes that consist of opinon and anecdotal observation without any science to back it up doesn’t go very far on this forum.

Wow! I’m absolutely done with this thread as we keep going in circles. Everyone can do their own research on Weyland, Mann, or whoever…compare and contrast for yourselves and make your own assumptions and opinion. I’m going to stick with Mann, Bosch, Tellez, Seagrave, Pfaff, and Winkler.

Canadian Athletics Coaches Centre is a phenomenal place to find videos and documents of best coaches in the world talk about everything under the sun in track and field. No videos on treadmill running of sled pulling though. Bosch and Klomp’s “Running, the BK Method” DVD and accompanying book are also incredible resources. Mann’s latest 2011 publication, “The Mechanics of Sprinting and Hurdling” is a culmination of over 25 years of research and former publications on the best sprint/hurdle athletes in the world. It is cool because he presents the data for the biomechanic geeks then gives suggestions on how to actually present the concepts in a simpler manner to the athletes.

All of the most successful coaches all say pretty much the same thing, but just in different ways…which is what I think Star and I are doing. Short GCT are the result of fast sprinting is a little like saying bending stronger poles while pole vaulting is because of higher pole vaulting…well, yes…that’s the bumper sticker version, but there is an orchestra of factors at work. See you all on another thread perhaps.

Don’t be so sensitive! Star61 is just trying to interact with you. There is nothing wrong with questioning your assumptions.
IMHO the problem you are having with this thread is that you are trying SO desperately to show that you know so much!!! Calm down a bit. You are clearly a well read guy with lots of Sprinting background. You have a LOT to add to this site but… when you write 3 and 4 paragraph posts then it doesn’t really leave much room for discussion from the rest of us. If you write shorter posts with one or two central concepts then you will generate more interest.
I look forward to seeing more posts from you in the future.

I agree with macsprint. I also agree with star as ground contact does decrease as speed increases not the other way around. Clymb420 you have many valid points and front side mechanics are dependent on the amount of time you spend on the ground. From my on personal experience and videos I have posted I tend to push too long which doesn’t leave me enough time to recover and get good front side mechanics. With that being said some athletes do need to be cued to purposely reduce the gct or amount of time the foot is left on the ground to prevent pushing out the back. I learned that last statement from a few of Charlie’s posts. Thanks

Hi Izzle and Mac, I don’t think my exclamation was sensitivity to Star’s comments, as we’ve had the same exchange 3 or so times now in this thread, but frustration with myself that I have spent so much time (and typing) on this one thread…going round and round and not going anywhere. Especially since it was not having a direct relationship with thread starter’s question. I am aware of my tendency to get carried away. I do have a long post problem when challenged, and I will work on it. I was and still am excited to have found this site…didn’t know it existed until a couple of weeks ago. All that excitement has poured out in these last several posts of mine on this thread. Also, I am an oldest child so I like to share. I am now really done with this thread as I think original question of “what are front mechanics” has been answered. Looking forward to your next video Izzle. Hope to see you all on another thread.