by Kristy Parrish | March 23, 2016 2:00 am
Starting Stronger: Article 1 is the first of a series for optimal sprint mechanics for the pro athlete or the weekend warrior.
My guess is if you are reading this article, you are interested in improving your sprint mechanics. Why? To have faster speeds than your competition, develop a leaner body composition… the list of reasons to be a capable sprinter go on.
The first article in this series will be focused on general mechanics & the optimal start position. This will allow the athlete to consistently drive aggressively out of the start and set up for a fast sprint down the line. The set-up will become second nature with practice and quality repetition.
Much of my influence as a coach for sprint mechanics comes from Dr. Ralph Mann. He was an Olympic Silver Medalist in the 400m hurdles & 5-time national champion in the hurdles, and he earned several other national, collegiate and international titles. He started the Elite Athlete Program, analyzing specifically the sprint and hurdle events. His book, The Mechanics of Sprinting and Hurdling, is a definite resource for any sprint coach. His practices and models as a coach are based off the best sprinters the world has seen; thus for me as a coach, this is the gold standard for sprinting mechanics and speed development.
Elite sprinters were found to maximize Frontside mechanics and minimize backside mechanics. So in the sprint, the elite sprinters aggressively pull their upper leg into the high knee position to ready for the next step; in doing so, they minimize the backwards rotation of the upper leg, not letting it rotate underneath and behind (the “backside mechanics”).
So when it comes to accelerating, the goal is maximal development of force down the line. What does this mean when it comes to executing the start? The athlete pushes off from the start, driving down the track. The ground contact times are longer, and as the athlete reaches higher speeds, they shorten as a result. “Quick” can sometimes connote a shortened ground contact time on the start, resulting in slower top end speeds down the line. Longer powerful ground contacts are normal during acceleration. The athlete is not jamming their leg into the ground but instead aggressively pushing down the track.
To react quickly, accelerate forcefully! So our goals on this acceleration will be as follows:
For the purposes of this article, we will say we are racing out of a 4-point stance. The set up for the 3-point stance will be very similar, albeit with one less hand on the ground.
Once we have your legs determined, we will now work on our set up. Most sprint events that require you to have a start from a 3-point or 4-point start will have a line for set up. We will usually set up perpendicular to this line.
I want to give you our end goal for what a proper start position looks like before we delve into how to set it up. The following figures are from The Mechanics of Sprinting and Hurdling: 2013 Edition by Ralph Mann, Ph.D., used by permission of the author.
So this is where we get into the details of the start and set position. It will take a bit of trial and error on set up. But thankfully with coaches/friends or your trusty phone handy, you will be able to get some video to double check. The first angles we will look for in a solid start position will be about 45 degrees relative from the front of your shins to the ground. Your feet are firmly planted, ready to push through the ball of the foot, not the heel. Secondly, we will look for about 90 degrees behind the front knee, relative from the calf to the hamstring. On the back leg, we will look for about 120 degrees from the calf to the hamstring. Give or take a few degrees, this will be our optimal angles for acceleration: this will allow us to effectively push out of our start position aggressively and allow for large pushes against the ground down the track. The whole start should be just that — a PUSH! This will allow us to effectively apply force to the ground, as opposed to a “pull.”
Hand position in the 4-point stance will be right behind the line, with the hands bridged up. Thumb and fingers will be parallel to the line, in the neutral position. Arms should be straight, and down about shoulder width.
During the start and continuing acceleration, we will be looking for complete extension: triple extension at the ankle, knee and hip! This allows for maximal force application — you push the ground, the ground pushes back = you go faster!
On the first step, we will look for the complete extension through the ankle, knee and hip. This should look as close to a straight of a line as possible. The first step should land underneath the sprinter and slightly behind the center of mass, landing on the ball of the foot. We don’t want to land too far forward, as this will create braking forces and make it harder to accelerate efficiently on the next step. Think that you are aggressively driving the knee forward, landing on the ball of the foot.
As the foot from the first step contacts the ground, it lands on the ball of the foot underneath the center of mass. This allows for the effect development of horizontal speed. As the foot lands, the athlete is trying to “paw” the ground as fast as possible to efficiently maintain speed over the duration of the ground contact and minimize braking forces.
During the entire sprint — with the exception of the foot takeoff on the ground phase — the athlete should strive to keep the toe dorsiflexed so as to allow an efficient lever for ground contact forces, as opposed to letting the toe “point” into plantar flexion, which creates inefficient ground contact forces and more than undesirable breaking mechanics.
It is important during the ENTIRE acceleration that the ground contacts are not rushed! Too many times you will see athletes try to be “quick” and run “lightly,” but what this accomplishes is short-changed extension from the joints and less than effective force application to the ground. Comparably to the rest of the race, the acceleration is shown to have longer ground contact times as the athlete accelerates. As they reach top speed later in the race, the shorter ground contact times will occur as a result of the high vertical forces. Don’t be afraid to allow for big, powerful pushing steps on that acceleration. The shortened ground contact times are a RESULT of high forces being exerted into the ground. When cued properly, the short ground contact times will occur as we achieve a top end speed, but typically shouldn’t be cued to avoid less then optimal force outputs. This will add up to higher top end speeds down the line.
We will finish this two-part series in a later article, covering maximal velocity mechanics.
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