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Creating Efficient Horizontal Propulsion© 2006 by Ken Mierke and Joe Friel

Despite what most runners and their coaches believe, technique plays an enormousrole is sustained fast running. Most runners’ subscribe to one of two basic paradigms
of propulsion. Unfortunately, both are flawed. One creates more upward propulsion
than forward and the other isolates a relatively small, weak muscle group instead ofharnessing a number of muscles to work together to produce propulsion.
Upward Thrust Method
One challenge for runners is creating propulsion as close to purely horizontal aspossible. Excessive vertical displacement increases the energy cost of running
dramatically. The most common method runners use to develop
propulsion is the upward thrust. At toe off, the knee isstraightened forcefully, thrusting the body up and forward.
This technique wastes a tremendous amount of energy, leads tolocal muscular fatigue in the quadriceps, and slows turnover.
As indicated by the large black arrow in the illustration, thedirection of the force created by extending the knee is slightly
forward, but mostly upward. The slight increase in stride length ismore than made up for by decreases in turnover rate caused by
the extended flight time during each stride, resulting in slower running speed andincreased energy cost. This up and down method of running, employed to somedegree by most runners, is extremely inefficient. If an athlete’s quadriceps fatigue
during long runs even at easy pace, he probably subscribes to the upward thrustparadigm.
The quadriceps muscles work in the vertical plane. On flat ground, the quadriceps
should only contract at the moment foot-strike to hold the body up. The quadriceps
should minimize knee bend at foot-strike, but should not create propulsion. Thequadriceps should only be propulsive in uphill running.

Pull Through Method
A somewhat less common error of propulsion is the pull through. This runner avoids
the upward thrust push-off, instead creating propulsion by bending the knee and pulling
his body forward with the hamstring muscles. This running style is reasonably energy1www.Fitness-Concepts.com
efficient: it does minimize vertical displacement and landing impact.
The problem with this running style is the demand that it places on
the hamstring muscles.
The hamstring muscles are relatively small and weak. When they
are almost exclusively responsible for propulsion, they fatigue easily.
Using larger muscles, with the hamstrings, enables a runner to takeadvantage of the benefits of the energy-efficient (horizontal) style,
but prevents local muscular fatigue in the hamstrings by spreading
the workload over greater muscle mass.
If an athlete suffers from hamstring fatigue or cramping during longor hard runs, while the rest of the body feels fairly comfortable, he probably uses pullthrough propulsion. Learning to engage more muscle for propulsion while maintaining
the horizontal movement will increase speed and endurance.
Foot Drag
The two common errors of creating propulsion for running involve movement at theknee. Optimal technique for creating propulsion when running on flat ground requires aconstant knee angle through the propulsive phases of the stride cycle.
I (Ken) call the recommended technique the foot-drag movement. It involves pivoting
the leg backward from the hip with the entire leg as a fixed unit.
The knee should be slightly bent, but the knee angle should notchange from just before foot-strike, through the period of contact
with the ground, to the follow-through. Through the entire
propulsion phase, the knee angle should be slightly bent andconstant. This technique accomplishes a number of goals ofefficient, fast, sustained running.
First, the foot-drag movement creates almost perfectly horizontalpropulsion. Vertical displacement, and all the problems
associated with it, can be minimized. Newton’s Law states that “every action has anequal and opposite reaction”. It follows that, in order to create horizontal propulsion, wemust pull straight back against the ground instead of pushing down into the ground.
The foot-drag movement accomplishes this goal.
The foot-drag movement also takes advantage of the attachment points of the muscles
on the back of the hips and thighs and spreads the work of propulsion among a muchlarger muscle mass than other methods of propulsion. Using greater muscle mass toaccomplish a certain amount of work decreases the relative intensity of the work for2

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each muscle. If more muscles are doing the same amount of work, each muscle isworking more easily.
The hamstring muscles are unusual in that they cross two major joints. The hamstrings
attach above the hip, cross both the hip and the knee joints, and attach below the knee.
Due to this unique attachment, they serve two major functions: extending the hip joint
and flexing the knee joint. The gluteus maximus muscles, on the other hand, cross only
one major joint, the hip. The glute muscles only major action is hip extension.
The pull-through method of propulsion creates nearly horizontal propulsion, but it fails
to engage the largest and strongest muscle in the body, the glutes. Which do you thinkwould be stronger, your hamstring muscles, or your hamstring muscles plus yourglutes? That answer is obvious. If knee flexion is the primary producer of propulsion,
the hamstrings have to create the force by themselves. By using hip extension insteadof knee flexion to create propulsion, the hamstrings work in conjunction with the glutes,
therefore each muscle is required to produce less force. Obviously, this minimizesfatigue.
Pull-through runners frequently have extremely tight hip-flexors, preventing correct hipextension. Stretching these muscles will enable you to incorporate better technique fordeveloping propulsion, allowing you to create high levels of horizontal propulsion
without local muscular fatigue.
Developing a stride which uses hip extension as the primary method of propulsion will
enable runners to move more horizontally and to use large muscle groups to do thework. This will allow you to run farther and faster that ever before.
Ken Mierke is author of The Triathlete’s Guide to Run Training, Head Coach of Fitness
Concepts (www.Fitness-Concepts.com) and creator of Evolution Running. Two of Ken’s
15 clients used these techniques to win World Championships in 2005. Our
instructional DVD is available at www.EvolutionRunning.com Joe Friel is author of The
Triathlete’s Training Bible and co-author of Going Long and The Paleo Diet for Athletes.

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