Latest / The Gill Athletics Track and Field Connections Podcast / #15: Gill1918 presents Evan Nelson "Step Rate as a Teaching Tool"

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#15: Gill1918 presents Evan Nelson "Step Rate as a Teaching Tool" · The Gill Athletics Track and Field Connections Podcast

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Welcome to the Gill 1918 Project, a podcast series by
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coaches, for coaches powered by Gill Athletics.
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Think of this as the Ted Talks of track and field coaching.
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Short, insightful, and packed with valuable strategies to help
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Check out the show notes below For more information.
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Now let's get into today's topic.
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This is Evan Nelson from the University of Wisconsin and
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today we're going to talk about using stride frequency as a
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coaching tool for running bio mechanics.
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Stride frequency, step rate or cadence are synonymous terms
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that people in the running community may know.
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Step rate or cadence is a really common topic in the adult
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running community and is a base function on most running
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watches. Now actually I'm going to use
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the term stride frequency in this podcast because it because
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it's the most common term in track and field or cross country
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coaching education. It's really important for
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everyone to know that an ideal or optimal stride frequency does
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not exist. A runner specific stride
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frequency is individualized, individualized based on running
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physical characteristics and will change with running speed,
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terrain, or environmental condition within the running
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community. A cadence of 180 steps per
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minute or 90 strides per minute is frequently advocated for, but
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this is not a universal ideal and should not be the goal for
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all runners. Research has shown that a lower
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stride frequency is associated with running related injuries
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and evidence informed recommendations and advise that
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the stride frequency should be at least 83 strides per minute
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or 166 steps per minute. I'd like to be clear that a low
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stride frequency doesn't cause running related injuries.
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Instead, the stride frequency may indicate how forces are
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being applied to the legs. The mechanical load from these
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accumulated forces is the cause of nearly all running related
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injuries. So let's get into discussing how
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we can use this to our advantage. 1st, I'm going to
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provide some fundamental concepts that many listeners
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will know, but I want to make sure that the basic principles
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are clear to listeners who are just learning about stride
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frequency for the first time. Second, I will describe how
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changing stride frequency will change a runner's bio mechanics.
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And 3rd, I will present reasons why coaches should use stride
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frequency manipulation as a tool to change running bio mechanics.
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A running stride is 2 steps, one with the left foot and one with
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the right foot. The distance traveled in those
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two steps is the stride length. How many strides a runner takes
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each minute is the stride frequency.
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Therefore, the stride frequency will be half of the step rate or
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half the step frequency. Running speed is a function of
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both stride length and stride fat frequency.
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So running faster requires you to increase your stride
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frequency, increase your stride length, or increase both stride
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frequency and stride length. Because speed determines the
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winner of all running competitions and is and nearly
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all track and field events, coaches and athletes are
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inherently motivated to accept any technique a runner uses to
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maximize speed. However, when speed is held
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constant, taking more strides per minute will decrease the
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length of each stride. This reciprocal relationship of
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stride length and stride frequency is a biomechanical law
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that creates a valuable tool to change running form.
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When running at the same speed, taking more steps per minute
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will automatically shorten the length of each stride.
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When used in this way, stride frequency is a tool to change
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running gait and reduce the mechanical load imposed by each
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stride. Now I will explain how to
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effectively teach runners to change stride frequency while
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they're running. Is the easiest to learn this and
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learn how to manipulate stride frequency on a treadmill where
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speed does not change. If running outside, it is really
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important to monitor running pace and make sure running speed
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does not increase while trying to run with a higher stride
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frequency. While running at a typical
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running pace, count the number of strides taken in one minute.
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For example, have your runner count the number of times the
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right foot hits the ground in 60 seconds.
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Multiply the higher stride frequency by.
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Multiply the stride frequency by two to get the step frequency,
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increase the step frequency by three to 8% to get the new
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higher prescribed step frequency and set this on a metronome.
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You can use an iPhone free metronome app or some running
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watches. Have metronomes built in?
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Just use an old fashioned metronome if you have one.
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It's a lot easier to use step frequency because each foot is
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going to hit the ground to match the beat of the metronome in a
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very symmetric pattern. If you use step frequency while
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running at the same typical running pace that you used to
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count, the strides that you took increase how quickly steps are
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taken to match the beat of the metronome.
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Maintain this stride frequency while running at the constant
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typical running pace. The audio feedback provided by
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the metronome is a quick, cheap, and effective way to increase
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stride frequency. As long as the speed remains
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constant, increasing stride frequency will decrease stride
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length and provide the biomechanical benefits.
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It's important for coaches and runners to realize that
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shortening stride length does not make the runner slower.
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The running speed is exactly the same.
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I'm advocating for using stride frequency as a simple evidence
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based tool to change running form.
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As a tool intending to change a movement pattern or motor skill,
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it's important to apply stride frequency change using a
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thoughtful approach. The audio beat of the metronome
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is extrinsic feedback that should be provided for short
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periods of time and repeated often during the initial
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session. The runner may need the
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metronome feedback for up to 15 continuous minutes, maybe less,
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but be prepared for them to use it for a while.
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While accumulating to the new stride frequency, the runner
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should internalize how it feels to run in the new style.
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The runner should pay attention to how the foot feels as it
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contacts the ground, the position of the legs throughout
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the gait cycle, the speed of the leg turnover, and the position
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of the trunk and upper body. Focusing on how it feels to run
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with a higher stride frequency helps the runner learn the
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intrinsic feedback cues that come from within the body during
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subsequent stride frequency training sessions.
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Metronome feedback should be progressively shorter in
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duration and used for less periods of time.
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A common strategy is to listen to the metronome for one to two
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minutes to check stride frequency before shutting off
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the metronome for a period of time while the runner tries to
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maintain the new stride frequency.
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This pattern of interval, like audio feedback, is an effective
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teaching tool. Runner should become more
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accustomed to how it feels to run with a higher stride
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frequency and become progressively more reliant on
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intrinsic feedback with less need for extrinsic audio
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feedback. We use this strategy often in
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running medicine clinics with great success.
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Runners often become proficient within two to four weeks when
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they're running four to five or three to five days per week.
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More frequent practice should decrease the time until a runner
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becomes proficient with running at the higher stride frequency.
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Treadmill running is great for learning to run with a higher
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stride frequency because it's really easy to assure running
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speed remains constant. However, most runners prefer
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outdoor running, and most running events don't use
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treadmills. Outdoor running will rely
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heavily on intrinsic feedback. Runners must learn that what it
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feels like to run with a higher stride frequency and intuitively
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be able to feel when they're doing it correctly versus
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incorrectly. Most runners initially describe
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running with a higher stride frequency as weird, abnormal,
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choppy, or like they're running on a wheel.
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Runners who feel that the higher stride frequency is natural or
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no different are probably doing it wrong.
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As the runner transitions to outdoor or Overground running,
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it's vital that running speed doesn't increase when the as
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this runner increases their stride frequency.
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The only way to use stride frequency as a tool to shorten
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stride length is to maintain a constant speed, and that shorter
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stride length is where the biomechanical benefits really
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emerge. Paste intervals are.
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Using agps watch to monitor running pace are effective
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strategies to run at a constant speed while running over ground
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or outside. Extrinsic metronome audio
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feedback may be used as the runner initially transitions to
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over ground running, but the real goal is to quickly
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transition to intrinsic feedback.
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Intrinsic feedback is preferred because the running style, using
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a shorter stride length and higher stride frequency will
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continue to provide the biomechanical benefits when
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running on different trains, in various environmental conditions
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or at different speeds. Coaching athletes to run at a
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higher stride frequency will require some additional nuance.
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Coaches should identify and emphasize the connection between
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running form drills that encourage faster like tone,
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turnover and stride frequency with that runner's quote UN
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quote normal running. This is a common practice for
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coaches of Sprint athletes and coaches of distance runners
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should adopt this practice. Athletes must remain vigilant to
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intentionally run with a higher stride frequency because it will
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take a long time for this new motor program to become their
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innate running style. Coaches should offer queuing
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encouragement and feedback as runners adopt the higher stride
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frequency. Appropriate comparisons can be
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made with hurdle or field event coaching.
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Coaches in these disciplines provide some biomechanical
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instruction repeatedly using a combinations of cues or
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instructional strategies. They also provide their athletes
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with repeated opportunities to learn new skills and expect
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imperfection along the learning process.
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Runners will require similar coaching to adapt stride
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frequency. Coaches can expect changes in
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running form to require greater metabolic and cognitive energy.
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Temporarily, this will require more effort and concentration
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from the runner. Changing running form during the
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offseason or or early in the season is much smarter than
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making these changes close to important competitions.
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I'm going to take a moment to talk directly to coaches of
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running teams. Initial training and stride
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frequency changes are best done with an individual runner, and
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they're very difficult to do in a team setting.
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The extrinsic audio feedback that is one of the most
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effective strategies to teach this skill would would be total
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chaos if a team is trying to run together with multiple
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metronomes beeping at slightly different frequencies.
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I'm working on new methods for coaches that teach stride
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frequency during normal team practices, but these are still
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in development at this time today.
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What I'm recommending coaches do is that they advise athletes to
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initially learn the new stride frequency using a metronome
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while they're running alone. Maybe this is on a weekend
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during the offseason in replacement of a team practice,
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or on a day when the team does not formally practice.
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When runners are able to use, excuse me, intrinsic feedback,
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it becomes much easier to continue stride frequency
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training during team training. Coaches can then integrate their
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stride frequency into the training as part of their normal
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training plan. But as an additional point of
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emphasis, their normal training plan would include all types of
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running like you'd normally plan, including short and long
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training runs, intervals, or speed sessions.
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As a coach, you should emphasize speed stride frequency
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throughout the training to allow runners to practice the skill
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and tell the desired biomechanical effects persist.
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Stride frequency is then a strategy or a tool to change
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running gait. This simple tool to change a
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running bio mechanics likely has wide application and use in
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young or novice runners. The simple technique may be
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useful for improving running running bio mechanics in middle
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or high school runners where the broad based interventions may
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positively impact a large percentage of runners.
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More selective application of stride frequency change is
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likely appropriate for collegiate or elite runners who
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typically exhibit more refined running form and a higher level
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of biomechanical efficiency. Even though many runners will
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benefit from increasing stride frequency, it's possible for
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stride frequency to be too high. Excessively high stride
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frequency reduces the ability to optimally benefit from the
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propulsion because the foot simply leaves the ground too
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quickly. Check stride frequencies that
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are greater than 100 strides per minute or 200 steps per minute
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for under striding. Additionally, runners with good
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bio mechanics may not need to change the way they run.
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Recently I had a coach tell me they work on running form every
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day in practice. They do form drills, emphasize
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form with the runners, and use devices such as hurdles,
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ladders, and cones for gait training.
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That coach didn't see a need to use step rate and they asked me
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why they should consider it. The carryovers is probably
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better than cones, hurdle drills, or other form drills
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because runners learn this strategy to run using a higher
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stride frequency while they're running as they normally do, but
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more importantly, manipulating stride frequencies.
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The only technique proven to improve critical running form
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efficiencies using a single training technique or strategy.
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Bounce too much up and or too much up and down motion, as well
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as over striding or excessive lower extremity compliance all
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improve when stride frequency increases.
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I'll explain why each of these characteristics is inefficient
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and how changing stride frequency may be beneficial.
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Excessive vertical displacement or bounce too much up and down
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movement increases the load the body must accommodate on every
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stride. The extra up and down motion
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causes forces to be imposed on the body and requires muscles to
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do work. But none of this extra work is
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contributing to forward motion. Instead, the additional forces
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adding load that may cause injury and make the runner get
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tired more quickly. Multiple research studies
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involving runners of all ages, abilities, and experience levels
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consistently show that increasing stride frequency
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while continuing to run at the same speed causes an immediate
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reduction in vertical displacement.
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Over striding describes a runner whose foot contacts the ground
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too far in front of the body. When the initial contact of the
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ground occurs in front of the body, a breaking force is
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created that pushes the runner backward.
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Braking forces are inefficient because the runner must overcome
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this backward force in order to run forward.
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The farther the foot lands in front of the body, the larger
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the braking force. If running speed doesn't change,
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increasing stride frequency stride frequency will
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automatically reduce stride length and reduce braking force.
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Leg stiffness describes the elastic properties of the body.
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The concept of stiffness can be thought of as the legs ability
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to absorb energy as it added as it's loaded with body weight and
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then return that energy to spring the body forward into the
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next step. Tendon stretching and elastic
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recoil is one important way the body absorbs, stores, and
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returns this energy. Leg stiffness is better when the
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hip, knee and ankle joints absorb energy without being
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excessively compliant. Excessive compliance creates
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energy leaks and running inefficiencies that decrease
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lower extremity joint stiffness. Coaches can visually see
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excessive joint compliance because excessive motion looks
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like bad running form. Now coaches you routinely have
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use of multiple strategies and they have a whole lot of cues to
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limit runners excessive joint motion.
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But the elastic component of legs stiffness is impossible to
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visually observe. Fortunately, humans can increase
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leg stiffness by tightening muscles to create a stiffer
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spring that returns energy better.
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Asking the runner to consciously tighten certain muscles while
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they're running would be pretty dumb, so we need to use a an
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unconscious strategy to increase like stiffness.
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Sprint coaches training athletes to use a higher stride frequency
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are also increasing like stiffness as a method to improve
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Sprint performance. However, sprinting desires
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really long stride length and high stride frequency to
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maximize running speed, and maximum running speed is an
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unreasonable expectation for training or racing longer
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distances. But the idea of stride frequency
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is still a method that can increase leg stiffness.
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A study performed by Brian Eiderscheit and colleagues here
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at the University of Wisconsin in 2011 showed that multiple leg
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muscles changed in their timing of contraction when stride
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frequency increased in people who are running over distances
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at lower velocities, not sprinting.
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The leg muscles were active before the leg hit the ground
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rather than after ground contact.
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This early activation of leg muscles prepares the leg to
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impact the ground and also increases like stiffness through
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the muscle contractions. The important unconscious change
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in leg stiffness allows the leg to store and return energy more
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efficiently. Middle or long distance a
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runners can improve running bio mechanics to optimize mechanical
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efficiency. When running speed remains
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constant, running at higher stride frequency decreases
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bounce, decreases over striding, and improves leg stiffness.
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So without changing a runner's pace or speed, increasing stride
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frequency produces positive changes in running bio mechanics
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without much active thought by the runner.
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Runners therefore can remain focused on running and the
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training intent of each running session.
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Coaches who strategically apply stride frequency using a motor
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learning strategy can change a runner's form relatively rapidly
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and here unlocks the power of why we should consider this as a
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tool to adapt our runners bio mechanics.
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Thanks for listening. Hey gang, Mike Cunningham here.
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Hey, I hope you enjoyed this episode of the Guild 1918
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Project series. It's really my mission, my
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passion to bring you massive amounts of value and I hope this
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one hit the mark. The Guilt 1918 Project is really
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dependent on you if for you to build your own episode, to hear
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your voice, to have your voice heard you have something to say
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and teach other coaches out there.
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So please get a hold of me, E-mail, text message, Twitter,
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Hope you enjoy the day, they will see you tomorrow.