Jul 16, 2012

Strength Training for Runners: Part II

Strength Training for Runners: Part II
By Jacob Goodin, BS

In the first installment of this series, we discussed the rationale behind strength training for endurance athletes, and emphasized that it is important to perform non-running-specific work if it allows you to train at a greater volume or intensity without getting injured.  In Part II we will present you with 4 ways that strength training both directly and indirectly improves running performance.

1. Indirect: Lets you train with greater volume and/or intensity

This point can’t be stressed enough. A program that addresses general physical preparedness (GPP) raises the durability of the body’s mechanical systems, allowing it to better absorb and adapt to the stresses that all those track intervals, long runs, and hill sprints put it through.  Although this is an indirect effect, it is by far the most important.  For more on this, see Part I.

2. Direct: Increases stride length (SL)

In intermediate and veteran runners, chances are that leg strength and power have plateaued, and even decreased from starting levels.  The body has developed adequate strength to propel itself forward a certain distance with each step (SL), and if you multiply this by the number of steps you take per minute (stride frequency, or SF), you get your running speed.  With this knowledge, lets take a look at the typical female collegiate runner.  Her training consists of long runs, threshold runs, interval work, short sprints, and even certain plyometric drills like bounding and skipping, so obviously she is working one end of the strength-power spectrum quite well.  She has a current 1 mile PR of 5:11, and a video analysis of the race reveals that her SL was 6’2” (6.17 feet/step) and SF was 165 steps/minute (which, if you do the math comes out to a 5:11 mile).  If this runner adopted a strength program that addressed posterior chain strength, power, and stiffness and thereby increased the SL that she could sustain in her mile race by 1 inch (without any decrease in SF), then on paper she can now run a 5:07 mile.  The competitive runners reading this know that those 4 seconds can mean the difference between advancing to the next round or going home, winning or losing.

3. Direct: Increases stride frequency (SF)

Continuing with the above scenario, if through proper neuromuscular training this runner could increase her SF from 165 steps/minute to a more optimal 170 steps/minute, while maintaining a SL of 6’3”, she would now be able to run a 4:58 mile.  This type of change takes not only a very conscious effort during running, but also an increase in the nervous system’s ability to contract and relax quickly and sustain it for the duration of the race.

4. Direct: Improves stride efficiency (SE)

This female runner can work on increasing her SL and SF until the cows come home, but if she doesn’t also improve her stride efficiency (SE, also known as running economy), she will never reach full potential.  SE is a lot harder to quantify than SL and SF, but is defined as the energy expended per stride at a given speed.  Decrease the energy expenditure per stride, and suddenly you can run for longer at the given pace before tiring.  Spending more time running is the best way to accomplish this, and most runners already do that.  But runners should also be ironing out asymmetries and muscular imbalances, stretching and foam rolling tight and adhesed tissue, and strengthening weak muscle groups.  This will all contribute to a crisp, more stable running form that loses no energy to small accessory motions, inefficiencies, or unstable joints.  In other words, all of the runner’s energy will go directly into forward propulsion instead of being lost somewhere along the kinetic chain.  This will lower the energy cost of running and ultimately allow the runner to hold her speed for longer.

Wrap Up

If you are serious about tapping into your full potential as a runner, then it’s time to get serious about utilizing the full spectrum of training available to you.  Adding a consistent and well-coached strength routine to your training will not only allow you to add volume and intensity, but could very well make the difference in your long-term development through improvements in SL, SF, and SE.

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