Trismarter Run Analysis Literature: Part 1


Trismarter Run Analysis Part 1: Body Position

By Lee Gardner | Published: May 2, 2012

For athletes seeking to make improvements in their running form, Trismarter offers a run analysis service. The basis of our running form philosophy is that all movement while running is focused towards a common goal of forward propulsion. This simply means we take into account the entire body position and its movement at every stage within a single stride, analyze and correct the position and movement as needed to positively effect the runner’s efficiency, and thus effect the runner’s ability to travel faster and further. For purposes of this series of articles, I’m going to touch on common inefficiencies that we see regularly in triathletes and runners that can easily be fixed by simply being aware of them, making minor adjustments, and putting into practice the changes suggested to positively impact running. In Part 1, I address body position during the “drive” and “stance” phases of a single stride.
Running efficiently means that not a single movement within a stride negatively effects forward propulsion. Using the gravitational pull of this great planet we live on, we can place our bodies in a position to utilize gravity as much as possible to affect movement forward in space. With this in mind, I consider body position the single most important factor in increasing efficiency in running, specifically: a forward lean beginning at the ankles. By leaning forward from the ankles, we can take advantage of gravity and the momentum created, allowing our bodies to fall forward in a controlled manor. In a sense, running is just that: a controlled fall forward.
When analyzing a runner’s forward lean, we look for several key factors at varying moments within a stride. Measuring the body’s vertical angle from the insertion point of the femur up to the ear, we are able to see how effectively a runner is taking advantage of gravity, and thus how efficient the runner’s lean is at various moments within a stride. Typically, we measure the “drive” and the “stance” phases, first looking for the degree of angle in both moments during the stride. Most elite runners lean forward at a ten degree angle. An angle less than ten degrees indicates that the runner is “sitting up” as they run. As you can see in the photo to the right, showing a runner in both drive and stances phases, the angle of her drive phase is right at ten degrees, exactly where we want it. Looking at the stance phase, however, we can see that her body position has become slightly upright and the vertical angle of lean has lessened to eight degrees. Although not desirable, it is fairly common that runners will change the degree of forward lean as they move from drive to stance and back drive phases. In the case of this runner, her shoulders and head are moving slightly higher and back in the moments during the stance phase, in an attempt to generate additional power. She is at this moment in her stride under utilizing gravitational pull while simultaneously expending more energy to maintain speed.
There are two very effective exercises that a runner can engage in on a regular basis that will positively effect forward lean. The first, and simplest, is hill sprints or hill strides. By sprinting up a 5-8% grade at near maximum effort, focusing on a high cadence and a forward lean, the runner is forced to place his or her body in the correct leaning position. The second exercise is to have the runner drag a car tire behind themselves using a harness and a rope connected to the tire (I prefer compact car tires). Starting with short sets and gradually building in number of repetitions and duration, the athlete simply runs at varying degrees intensity from moderate hard to sprinting efforts. The weight of the tire forces the runner to lean at the ankles, assuming an effective forward lean.
Finally, there are also several unwanted effects of not having an effective forward leaning body position, which include (but are not limited to) over striding and a severe heel strike, both of which can lead to injuries of various types in runners. Additionally, by the very definition of an efficient running form, efficiency improvements will allow you to run faster for greater distances with less effort.
Danielle Mack is professional Triathlete residing in Boulder, Colorado. She found her passion for triathlons at a young age. However, it wasn’t until she turned sixteen did she really start training strictly for triathlons. Through various paths God has lead her through the years including Xterra’s and Adventure Racing she discovered her ultimate love, long course triathlons, especially Ironman’s!