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.
clymb420,
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.
Thanks Clymb…I’m looking forward to getting more feedback from you…You shouldn’t leave this post just yet because we know what frontside mechanics are because we still need more info on how to improve frontside mechanics…I would really appreciate your input.
I listned to Ralph Mann at a conference last year. The gist of it was - increased strength with sound technique i.e. with frontside mechanics = faster more powerful ground contact during sprinting - simple, and only one paragraph.
Did he mention ways to improve frontside mechanics?
Question for everyone. Mann’s assertions, or at least the assertions made by those referencing Mann’s data, seem to center around GCT, which is why I addressed it. In terms of reducing GCT intentionally (not just because your’re running faster) I ususally see references to terminating GCT early, or mimimizing backside mechanics. How does improving front side mechanics play into this? The only way I can see front side mechanics reducing GCT is to initiate GCT further under the body. Is there reliable data that indicates elite sprinters tend to step down further under the COG and sub-elite step down further in front?
Note: Even if it were true, any advantage could also be explained by reduced braking and not necessarily by increased frequency due to reduced GCT.
Front side mechanics can be improved with better posture. The knee simply can’t come up enough if the torso is not perpendicular or nearly so at max. velocity. and without that ideal posture, GCT will be increased due the survival mechanism/braking action-lean forward and the foot will land further ahead of the COM to “save” yourself and thus leading to a longer GCT. My belief on decreasing GCT due to improved front side actions is, in part, due to more powerful efficient counter thrust (I think that is the correct term?) that CF spoke of. If the arms/hands are coming up high enough to face or eye level, the drive knee will also come up in part as a reaction to those actions which have immediately preceded it-i.e. establishing or at least maintenance of correct posture and and active and complete arm swing. If the posture is correct and the arms are moving actively up and to the center line again as CF said many times, there is an improved “un-weighting” taking place on the support leg. That is, you will be on and the off that support leg more quickly referred by some as bouncing. Also, to clarify, the knee lift that takes place in the front side is a reaction to both counter thrust from the arms but also the reaction to ground forces and there should be no concious effort to lift the knees up higher.
Someone with more pronounced back side mechanics will usually not have proper posture and too much “dangle time” will take place with the recovery leg and thus that leg has a long distance and time to travel in the swing to get the knee up whereas I think most sprinters/coaches want to see the recovery leg/knee moving forward instantly when the foot leaves the ground. The athlete with more back side action relative to front side will take more time (I realize not everyone will agree with this assertion) and distance to get to the front-if it ever does completely.
Nice Post pioneer!
Thanks Pioneer. Is there any research that suggests sub-elite as a rule, tend to touch down further in front or toe off closer to center, than elites?
I am not sure what the article was called, but I have read that elites tend to touch down 5-11 centimeters closer to their cog than sub-elites.
Star61, I am not aware of any research that does indicate that with respect to toe off, though as Izzle1989 states, I too have seen some research that does indicate that for touchdown. Maybe someone else can cite the article(s)?
Further on toe off, I’ve seen personally witnessed numerous examples of athletes (with improper postural alignment) who’s heels came up higher than would be considered optimal. It was pointed out by Winckler at a track camp I worked at in the 90’s that those athletes who’s heels came up higher behind them than the norm (for lack of a better term) in almost every case had too much forward lean at or near maximal velocity-backs not held straight/possibly even slightly rounded forward and the pelvis down and not held neutral or “up”. This (heels coming up fairly high behind the athlete) was considered a symptom of overstriding-excessive back kick or butt kick.
I believe that part of the explaination I’ve heard over the years is that the athlete with the pelvis tilted “upwards” or in neutral will also have the advantage over those who don’t of placing the hip flexors on great stretch and thus the instant the foot leaves the ground this stretch (along with correctly and actively working the arms) will cause the knee of the support leg to move and actually be pulled forward which should be considered at least closer to ideal. Those athletes who’s pelvis is down tend to have their heels go up first with the knee moving forward later than would be considered optimal thus resulting in the extra dangle time and overstriding.
The elites have their knees moving forward once the foot of the support leg toes off with only minimal back kick whereas a non elite may or may not have this happen and a large part of this phenomenon appears to be a reaction to the stretch and the postural alignment but also as part of the arm action or in each case, possibly a lack of.
If you cannot hold Posture, you just running fast, not sprinting.
The reasons as to why you cannot hold posture are different for everybody, either due to tightness and or weakness from front to back and or left to right.
This is why you need a good coach - who can see these issues and fix them.
Once you have good posture, and move from running fast to sprinting, your GCT and front side mechanics Will be much, much better
This is exactly what I have learned about myself over the last four years. I had a lot of back-kick which would cause me to over stride and ease up during the latter parts of my races in fear of pulling a hamstring. Since then I have made it a focus to improve posture which I believe is the reason why I haven’t pulled a hamstring in over two years.
I have also figure out that mechanics cannot be improved if posture is not improved. If someone with less than ideal posture tries to limit the back-kick they will most likely cut off the stride too early which will limit force output. I know this because I have had problems with this. Now I just focus on having the best posture possible, pump the arms, and step down. Those cues have really help to make dramatic changes to my mechanics. I still have a long way to go but I now know that my training on the track, in the weight room, during stretches, and foam rolling are suppose to be geared towards improving my posture by releasing tension and/or increasing the strength of the antagonist muscles. Now I am focusing on release the quads/psoas while increasing the strength of the hip ex-tensors and abdominal muscles.