Monday, June 13, 2011

The Sprint, Kill, Eat Guide: Sprinting Yourself Back To Humanity. Part One.

Hopefully by now you realize that jogging is not only stupid but, it's also killing you. The purpose of this post is to take you from the slow crawl away from the lion that just mauled you to the full sprint into his den just to slap him in his stupid, non-human face. First off, let's examine some proper jogging technique:

Yep. That's about right. Make sure to increase your distance if you don't experience enough delirium. Ok, this is an extreme example and all fairness, Ironman's look really really hard and I have a ton of respect for the crazies that train and participate in these events... but this is just so much more badass:

What Makes a Sprint a Sprint?

The first obvious question after watching these two videos is, what is the difference between a sprint and a jog? The short answer is the speed of movement. A sprint is much faster than a jog... well, in most cases anyway.

At his top speed, he almost took two complete steps forward.

So, if speed is what dictates the difference between these two movements, then what the heck dictates the speed at which we move? Here is where things get a little crazy.

The first basic difference is the angle at which the upper body is positioned in relation to the ground when a sprint or a jog take place. Jogging requires a much more upright position and sprinting a much deeper angle, closer to the ground. For example:

You can see here a typical fitness enthusiast. relatively upright posture compared to the ground, hat pulled down just high enough so that he can see where he is going but low enough so that he can appear mysterious to all of the ladies he passes during his 10 mile ab-flex-fest around whatever city that is. Notice his perfect jogging attire. Hat, gloves, and sweatpants contrasting his skin tight JogTech Performance Tank Top and $400 dollar JogRight Fitness Plus Running Shoes. You may ask, "Why didn't he finish putting his gloves on?" When it's jog time, there is not enough time to strap up your jogging gloves. Fitness waits for no one. Even though I don't even know this guy and I hate him already, he actually has excellent running technique, I will explain why shortly... but I still hate him.

Now a sprint. Huge difference in upper body angle, huge difference in speed of movement. That backround is not a special effect. Bolt is accelerating so fast, that the high tech, high speed camera is having trouble keeping up with him.

Why is this angle so important for running speed? Ok, here is where I am seriously going to piss of A LOT of people. This angle is important because when sprinting THERE IS NO PUSH OFF. THERE IS NO PUSH OFF when you jog either. The propulsive force behind running, jogging, sprinting, and walking is gravity, not muscular effort. There is a term in running called the Extensors Paradox. This just explains how at peak knee flexion (basically right where Bolt's lead knee is in the above picture) the leg extensors deactivate as a response to the gravitational pull on the leg. This means when that lead foot hits the ground, there will be a hard contraction of the glutes, hamstrings, and calves as it moves under the upper body into a support position. At no point during this motion does it contribute to propulsive force. Crazy stuff, huh?

Think I am full of crap? Stand perfectly upright and try to push yourself into a sprint without leaning forward. If you tried this, you would jump straight up into the air. This is called vertical displacement. Jogging, walking, and sprinting are all horizontal displacements.

It should now be clear why this body angle is so important to speed of movement. How do you accelerate using gravity? You fall down. A sprint, a jog, and a walk are basically a series of falls and catches over and over again. The harder you fall, the deeper the angle you fall at, the harder you have to work to keep from smashing your teeth on the ground, the faster you move through horizontal displacement.

All things being equal, a stronger sprinter will be faster because they will be able to resist gravity at deeper angles. This is why most marathon runners look like they are starving to death and most short distance sprinters are jacked.

Funny thing about Usain Bolt, when he broke the World Record in the 100m, he accelerated at an angle of 21.4 degrees from 20m to 80m. Optimal acceleration angle is 22.5 degrees. So, if he could ever get to that acceleration angle, he has the potential to run the 100m in 6.75 seconds.

Still don't believe me? Still think there is a push-off and all of those stupid running mechanics textbooks are correct? Then explain to me how humans can run on frictionless surfaces?

If an actual push-off took place, he would have a mouth full of ice cubes.

Looking deeper into these concepts also eliminates stride length as a factor in running speed. The bodies reaction from the series of catches and falls now places emphasis on the speed of leg turnover (stride frequency) based on cadence (the number of times the foot strikes the ground per minute). Probably more information that is going to piss someone off.

The next few factors that translate into faster stride frequency and cadence are all very inter-related. Ground reaction forces (GRF), muscular tendon elasticity, and muscular contraction speed all play a big role in haulin' ass. Every action has an equal and opposite reaction. Every time your foot strikes the ground, the reactive force of the ground strikes back. Sometimes with upwards of 5 times your own body weight. This is the same force as when you first jump on a bathroom scale. You know how the weight shoots up really fast, then levels off at your actual body weight? That is a reactive force. Good sprinters are very efficient at storing the energy received from the GRF into the elastic components of muscle. The storage and dispersal of this energy during sprinting, or any cyclic activity like it, is due to a working mechanism of the body called the stretch shortening cycle. This system is meant to conserve as much energy as possible while performing actions like sprinting, running, cycling, and river dancing. There is tons of science behind this stuff but no one really knows why it happens. My personal belief is that it is a survival mechanism that has evolved after about a million years of either sprinting after our dinner or sprinting away from hungry bears and dinosaurs. Wherever it came from, we have it now and it can be trained to work more efficiently.

Contraction speed does not necessarily mean concentric (shortening) muscle action alone. A major factor that separates elite level athletes from novice athletes is the speed at which one can relax a muscle after concentric action. This ability to relax after contraction greatly contributes to the ability to shortening time in between cadence steps and increase stride frequency. Think about it, if there is interference from residual contractions after the lead leg has been pulled into flexion, the amount of time between relaxation and foot strike will then increase. Thus, decreasing cadence and stride frequency.

Now, the next question, which will be part two, is how can us normal non-elite level sprinters develop these skills and use them to augment the effectiveness of our training to reach our personal goals? It doesn't matter if you want to lose weight, gain weight, get stronger, get faster, or if you are just trying to become a more effiecient human, sprinting is a basic human movement that everyone should be good at. Back in the day, if you couldn't get up and run as fast as you possibly could, you either didn't eat or you got ate. So, for the sake of your own humanity, get good at it.

SPRINT!!!!!!! kill, eat.

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