Wednesday, November 26, 2014

Qualitative thoughts about running form

Built to Run: If you have been convinced by the science that upright-walking humans are formed over time to be the ultimate long distance running machines in dry hot weather.  If you have not heard this hypothesis and its supporting evidence, please click here.

Running Form: With a rudimentary understanding of human anatomy we can make some assumptions about the running form most conducive to our structure.  Some of the action verbs required to run:
  • Twist - the trunk 
  • Swing - legs/arms
  • Reach - reach in front and bhind
  • Absorb - landing, absorbing the momentum down loads the springs of the body 
  • Propel/Push-Off - propel over the landed foot, and extend legs, toe off.
Big to Small: Always tackle a problem big-to-small.  Working on the assumption that the biggest muscles need to bear the biggest loads.
  1. The glutes:
"The gluteus maximus is the largest muscle in the human body. It is large and powerful because it has the job of keeping the trunk of the body in an erect posture. It is the chief antigravity muscle that aids in walking up stairs."
The glutes do two things: keeps you from folding in half like a pocket knife and pushes your thigh from a raised position to a lowered position (sitting to standing).  If you have good upright, "hips-open" posture when running, you can dedicate this muscle group to absorbing and propelling the leg down and back.  If your posture is bad, you engage the glute to keep you from folding in half.  The glutes need to share their capacity to maintain your bad posture AND run.  The strongest movement of the glutes is pushing back - this is what propels you forward.  Try to fire this muscle when it contributes most.  The glutes are ~25% of your running muscles, make them do 25% of the work.  (25% pulled from the sky.)

   2.  The quads:

The next biggest cluster of muscles and cetrtainly the longest.  The Quads is an eccentric powerhouse, it absorbs your landing, turning all that downward momentum into stored energy.  The quads stops you from collapsing and in contraction straightens your leg.  It is the heel-cushioned running shoes that incorrectly allows you to straighten your leg WAY too soon.  Landing with knees slightly bent stored the most energy, straightening the leg should happen at push-off, firing simultaneously with the glutes.  It's the one-two punch of propulsion.  The quads are ~20% of your running muscles, make them do 20% of the work.  (20% pulled from the sky.)

  3. The trunk:

Twisting the trunk is often over looked.  We coach pitchers, batters, boxers, golfers, etc to originate motions in the hugely muscled trunk.  A perfect punch begins at the foot, twists the hips, twists the trunk extends the arm.  The arm is a messenger of the forces generated from the 'big boys' of the muscle groups.  Running is the inverse of that.  A trunk twist turns into a foot motion.  Twisting the trunk allows the reach portion of the running stride and extends the push off out the back.  The more the twist, the longer the stride (at the same cadence).  I think of the 'X' created by the shoulders and hips when I'm driving my knee forward and pushing out the back.  Arm swing exists only to engage this twisty spring mechanism.  The trunk is ~15% of your running muscles, make them do 15% of the work.  (15% pulled from the sky.)
4. The hamstrings
Next on the size-matters comparison is the hammies (I told you, conversational tone, this is no kinesiology class).  Hamstrings do the opposite of the quads, and fold the leg to make the knee drive easier.  The torque on the hip flexors during the swing phase is a function of leg weight AND leg length.  You can't lighten your leg, so make it shorter by folding it.  Engage hammies to bend the leg before (or syncopated) to leg swing forward.  This is why leg-swing-forward is referred to as knee-drive, not foot drive.  Hip flexors getting sore?  Try engaging hamstrings sooner! The hamstrings are ~12.5% of your running muscles, make them do 12.5% of the work.  (12.5% pulled from the sky.)

       5.  The gastroc chain

Shorten to 'the calf'.  Absorbs energy eccentrically allowing the heel to drop to the ground in a controlled manner.  Energy return happens at push off.  If you raise your heel with heel cushioning in your shoes then you're reducing the effectiveness of this energy return mechanism.  This is why people that transition to minimal shoes or barefoot in one day complain about calf soreness.  these > 1 inch heel raises in shoes limits the calf range of motion from 5-10%.  (reminder, if you see a '%' then the number is pulled from my rear, i meant he sky.)  The calf is not a muscle used to push the body in the air at push-off, it's relatively too small. Absorb, hold, return - it's due to fire at the end of the glute/quad firing and just before the hamstring folds your leg.  This phase in the running sequence is sometimes referred to as toe-off. Calves sore? Try lifting the foot with heel and forefoot at the same time - lift your foot flatfooted. The calves are ~7.5% of your running muscles, make them do 7.5% of the work.  (7.5% pulled from the sky.)
 6. The foot
Almost a copy paste from above, the foot muscle contribute a small but necessary component in the absorb/release phases.  Most important is that the foot is thought to contribute ZERO, so strap them to an unmoving slab of wood (eg 'supportive' shoe).  We ignorantly turn off any foot contributions by selecting the wrong shoes.  Let the arch load eccentrically and return it's share to the push off, that's what it's for!  The feets are ~5% of your running muscles, make them do 5% of the work.  (5% pulled from the sky.)

        7.  Others - supporting muscles that help (sometimes hinder) the balance and movements of these larger groups.  The shoulders, traps, glute medius, muscles for balancing, muscles for left-right (frontal plane) movements comprise the rest.

Summary: Asking too much from a smaller muscle group will limit your performance or distance quick!  Having an awareness of what's getting tired, sore or hurt will give you clues of what groups aren't pulling their weight.  Practice mindfullness with your runningfullness!  Remember, endurance isn't how hard a muscle can work - it's as much turning off the muscle groups when not in use.