One of the most commonly debated aspect of sprinting is the role of the arms in mechanics of the running cycle. Often we get onto various arguments with Ralph’s research or we start quoting the Dutch Boys but we need to trust what we see with our eyes (Kinematics) and appreciate the silent truth (kinetics) to verify what is happening. I am a firm believer of the Spinal Engine theory and fascial sprint concept, but not buying into the Anatomy Trains system from a locomotive perspective, so no superficial back line voodoo here! (Note: I have much of the Tom Myers work and enjoy it but we have some interpretation issues by some proponents that don’t jive with his perspective. On of our therapists is a SI person and he is awesome.)
The 90 degree cue is a common misconception but also a useful ploy for coaches to get athletes away from the old gymnastic running style that allowed a straight arm or the drummer boy style of allowing the elbow to move but eliminated the shoulder drive. I have cued 90 degrees with some athletes while cuing violent arm drive as the nervous system and motor programs may not be prepared to handle a more vigorous swing from the shoulders, resulting in either the drummer boy or straight arm error. The arms have an enormous influence in the gait as the stiffness relates to the body. First, their is less information on arm mechanics since much of the research says very little kinetic energy is created by the arm action in isolation. That is true, but the body is more integrated and requires a lot of things working to fully exploit speed. Here are some mistakes I have made in the past and here are some thing I have learned from those mistakes.
You can’t cure the technique with the wrong speed prescription- My biggest pet peeve is young coaches with great education and knowledge fail to prescribe the wrong speeds in training to correct technique. As the velocity increases the sprint mechanics become more influenced by reflexes and current strength and joint status. Intensive tempo often is a great technique tool since many of the issues with upperbody mechanics and the PH drop causes a choice for the athlete to relax and take the pain or tighten up and get more pain for longer (slower times). We are paranoid about overtraining and fast twitch conversion that running in the sprint world seems to be taboo. I like to do a lot of speed endurance work with young athletes to ingrain good running habits (and keep them from being lazy), only after some submax fly work is done to get a taste of speed so we don’t get lost in a world of submax speed. Simply put you need to spend a lot of time at the technical max speed, fast enough to get faster but not to the point the athlete looses control and become unaware of the feedback from the ground. If they are out of control cuing just doesn’t work for most situations.
Cue stiffy elbows and loose shoulders when needed- If you look at the elbow we know that the arms don’t straighten out all the way to 180 or close to 5 degrees either. I don’t know the average of the elbow joint during a full arm stroke but I would guess it’s close to 90 degrees, the number most coaches prescribe to correct crappy arms (I don’t know coaches that try to correct good technique with the 90 degree cue). If one swings the arms aggressively they should open up on the swing down (on the back swing) and if they relax enough they should close at the the top. That’s why I hate front side cuing on bounds since the whole arm swing is mainly lat but assisted by eccentric pec and concentric delts. With the lats involvement with sprinting . If you cue enough stiffness the arms clean up, you keep too loose you will see both the drummer boy and gymnastics run as the bicep and tricep need to synchronize properly. If you lock the the elbows too much the body becomes systemically tight or regionally tight in the arms. Like the swine flu, tightness instead of relaxation spreads fast and much of the problems step from the upper body.
Alternate means of conditioning can’t be abused- I try to use the minimal amount of running to keep people healthy but too conservative may cause injuries from lack of preparation and many athletes need to learn to run well. When we set the 4x400m school record at L-S years ago we were all good runners because most had cross country runs and needed only speed work to get better. While I am not a huge grass tempo guy, I think everyone should have a low dose amounts of running. I think that’s why Powell and friends do well as they just run more. I give Dan a lot of credit for alternative means but a lot of his disciples are not Dan Pfaff! The better the runner the less running they need and ironically those with good speed but awkward mechanics (errors) tend to stay away from a lot of running strikes to keep healthy and abuse alternative means. Use alternate means only when you need to not to mask running errors, loading schemes, and lazy athletes.