Can you or any of your Senior members advise me on how to correct excessive knee lift in a sprinter that I coach.
He has always had a good knee lift to horizontal ,but since introduing A and B skips ,fast leg drills and most of the other skips /drills in this genre I have noticed that he appears to be going above horizontal and starts to climb ,particularly during the mid stages of his 100/120 races.
He is a 10.9 100m 25year old sprinter who has 10 years sprint and weight training experience and has run a 21.60 200m at age 18.
The problem does not appear as pronounced in his 200m
Our training regime is centred around the CFTS and I know he is not realising his potential.
Could you give me some drills or tecnique advise on how to improve his forward knee drive.
PS. he has numerous minor hammy niggles/pulls thru his career and i wonder if this has any bearing on this topic?
Sorry guys,
(Been rather busy getting ready for conference so not on as much past two days)
Anyway, the Mach drills are as Charlie describes in the earlier post and the “new method” are also described above, and which you mention, the Speed Dynamics version, in which they believe you must force the pawing action. If you cant get your hands on the original book, purchase Charlie’s video set which demonstrates them rather well.
Often hamstring problems are related to hip and lower back tightness. Also low peak eccentric strength has been correlated with hamstring strains.
I just posted a topic on the biomechanics thread on A & B drills which should help answer your question.
how to correct excessive knee lift in a sprinter that I coach.
Weak abductor muscles of the hip can cause the hips to drop and the knee to be lifted excessively. Try incorporating hip extension on the hip machine this should help with proper firing patterns.
sprinter68,
How is the athlete doing the skips? Original Mach style or the “new method”
Does the athlete over-exxagerate this during drills?
Also what (rough estimation) angle is at the knee during sprinting? where is the foot (under the knee, past the knee, etc)?
Lower back tightness occasionly.
Full massage, once week on avg.
Regarding eccentric hamstring strength, athlete was tested at a University in Melbourne on a biodex dynamometer.
Results - length tension measurements (ie: 2x7 muscle contractions of knee flexor and extensor muscles: -
*Quads - right 24.8 deg, 243.0nm
" - left 25.5 deg, 240.0nm
*Hams - right 57.1 deg, 121.6nm
" - left 60.8 deg, 128.6nm
REPORT:
Quads “Never seen anyone with curves that overlap so well.”
Hams "Don’t overlap to the same extent.
Optimum angles for both legs at healthy lengths, however right is a fraction shorter by almost 4 deg. (Right hamstring has had more pulls/niggles than left hamstring)
NB. Athlete had a locked/frozen right SI joint, probably for 5 years b4 being picked up by a Chiro and a masseur - the latter has corrected and maintained its mobility to this time.
Read your topic on the bio thread on A&B drills and it has opened up a can of worms and doubts in my mind.
We have introduced and followed the “speed dynamics” methods of drills for the last five years, mindfull of the need to perfect them in a logical and gradual progression of skill and intensity.
We do one set b4 every training session and comp as follows: -
1x20m ankling
" butt kicks/ankle dorsi flexed/thigh below horizontal.
1X20m A&B skip
" Single leg fast leg
" Alternating fast leg
" Continuous fast leg
" Pawing
" A run
We have taped many training sessions and I started to wonder if the A&B skips and runs were causing the athletes knee lift to go above horizontal in a climbing action after the acceleration/conversion to maximum velocity phase.
As I said before, he has always had an effortless knee lift to horizontal in short sprints and maintained almost to a similar level in the 200m.
The more I view the tapes, the more I feel he is driving up, not forward with the knee and is losing stride length as a consequence. Cadence is very good.
Over to you!!
dlive11,
Thanks for your reply,
See also my response to Sharmer.
Athlete is doing skips modelled on and interpreted from the “Speed Dynamics” tapes.
What is the difference between the original Mach style and the “new method”.
Knee angle when sprinting: ie generally parallel or slightly above, with conscious effort and slight increase of his forward lean (he is a very upright runner) and running taller, the knee can be very slightly below horizontal.
I feel for a six footer, his stride length (49-50) for 100m could be better.
At ground contact of support leg, as best we can determine on freeze frame, at full leg extension, foot is behind the knee, toe in line with back of knee. (ie: about 60 deg angle between hammy and calf).
Is this what you are refering to?
Next frame, foot during flight is under knee.
Hope all of this makes sense!!!
Associating drills with knee lift in actual sprints is a problem because the dynamics behind each are different.
First the Drills. I favour the original Mach drills over all the bastardizations that have come along after. Trying to raise the knee after “stepping over” in a drill throws off the rythem and causes the butt to drop as the knee is raised. In these new drills, every time the knee passes parallel, it is pulled IN towards the body- exactly the opposite of what should be happening (watch all the drills carefully on those popular drill tapes and you’ll quickly see what I mean). This will NOT happen with well executed Mach drills.
Second, Actual Sprinting: In the sprint itself, the knees are NOT raised past parallel, in order to let the knee travel forward AWAY from the torso at full speed, allowing force delivery through hip rotation, and ease of movement. The LIFT, often described is of the WHOLE BODY, not the knees alone. Thoughts?
Can anyone point me in the direction of purchasing Gerard Mach’s book. I can’t find it anywhere. Also, is there video footage of these drills (maybe in the Vancouver Speed Training Series?).
DNHansen may still have some copies of the book. I highly recommend it. If you can’t find him directly. Inquire through info@charliefrancis.com and rupert will forward your request.
During A drills the knee is lifted excessively & the back leg doenst get triple extension. I have observed alot of athletes running up and down after doing these drills.
I believe that the hip work both flexion and extension on the hip machine and with cables can help alleviate this problem of going up/down.
Having a effortless knee lift is a good assist when combined with power, its my preferance to focus on strength exercises for the hip in the gym verse drills. These exercises should mimic knee lift & downward/backward extension of sprinting .
In terms of the right hamstring tightness incoporate long static stretches on tempo days or light days. Yoga or ballet stretchs can be great for alleviating such problems.
When viewing the video watch if the back leg gets triple extension, often this doesnt occur with excessive knee lift. The exercises i suggested will also improve triple extension.