February, 8, 2019
Dr. Weimar, it’s always fun to chat biomechanics with you. In addition to your lower extremity biomechanics research, you have a great deal of experience working with several Auburn athletes, which leads me to my questions below.
Q1: What is “the Hop” that went viral on social media with Auburn Softball, and how can it be used to enhance sports performance?
WW: The Hop is a preparatory motion before an explosive movement. We noticed the motion employed by greyhounds when they initiated a maximal acceleration, during a research project. The greyhounds picked their feet off the ground, landed (eccentric loading) and accelerated. It is based upon the notion of the Split Step that is associated with tennis and has been around for years. From our research we know that you reach peak force faster and greater peak force is produced, when you use the preparatory motion. We know that the stretch shortening cycle helps you jump higher and we think that it is because we are taking the “slack” out of the resting muscle and then stretches the muscle. In the Hop, instead of using a stretch shortening cycle (an eccentric/concentric movement) the dogs and our research suggest you use a concentric, eccentric, concentric motion. The concentric initiation takes the “slack” out of the muscle; it positions the muscle into a state in which the muscle can transfer force across a joint, a force large enough to cause motion. This muscle state is then activated eccentrically, so the stretch we are getting is more due to the lengthening of the muscle and not the removal of “slack”. So, when you are starting from rest, hop before you accelerate. Think about what happens when someone scares you with a “boo” as you walk around a corner. What is the first thing you do? You hop!
Q2: Switching gears a bit, what are some common mistakes that novice runners make from a biomechanical perspective that may lead to injury?
WW: This is a huge question! The answer starts from shoe choice and includes everything up to head motion. I will focus on two that have the greatest influence on performance. First, excessive side to side motion. It is lost energy expenditure. Excessive side to side motion can be the result of foot health/shoe choice, or can be an indicator of tightness/weakness along the kinetic chain. Second, over-striding. It forces the body out of alignment and you have excess motion in the transverse/horizontal plane. It also stops the body’s forward motion.
The key thing is the body will struggle to find the most efficient way to run. If the person is weak or tight, or has a foot failure, they will try and compensate for these break downs. The injuries come from either the original dysfunction or from the compensations. These dysfunctions can be seen as over-striding, poor arm swing, poor body alignment, and excessive side to side motion.
Q3: Over the past decade minimalist footwear has become a huge trend. Should folks jump right in and try it, or do you believe strategic planning is needed?
WW: NO, DO NOT JUMP RIGHT IN!!!!! Most people walk around in very cushioned sneakers; this teaches the body to respond to the cushioning and not the ground. However, when you change over to a minimalist footwear, your foot does not have the cushion between it and the ground. Your body’s own shock absorption system is set for running in cushions, so you have to “teach” your body to adjust the shock absorption system to the new loading conditions. The best approach I have seen involves working in the minimalist shoes into each run, and do NOT be in a hurry to go full-time minimalist.
Q4: I’ve seen you give demonstrations about how to properly lace up for sports. It’s impossible to describe this in writing I’m sure, but are there good resources for folks to refer to if they want to learn more about proper shoe lacing for running?
WW: Yes. The first lacing strategy we go with is called the Runner’s Loop. The purpose of this lacing technique is to bring the heel and the heel cup into better connection. Having the foot become one with the shoe will allow the foot to take advantage of the science of the shoe. We actually wrote an article about it with step-by-step instructions and pictures on how to do the Runner’s Loop. Beyond that, the next level of lacing strategy is dependent on the arch type. The lacing strategy may need to prevent the foot from floating laterally on the foot bed, or tighten the shoe over the mid-foot.
Q5: What are some future research areas that your laboratory are exploring?
WW: Our main focus currently involves looking at how the body adjusts to different surfaces. We are doing a study now analyzing various artificial turf surfaces versus natural turf. We also have some ideas regarding the efficacy of several exercises and preparatory movements on performance. Stay tuned!
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