389: Dave Kerin on Curvilinear Sprinting and Rotational Dynamics in Athletic Movement

Today’s podcast is with David Kerin. Dave is the USATF chair of men’s development, and also chair for men’s and women’s high jump. Dave’s coaching career began with 14 years at the HS level followed by 14 years of collegiate coaching where an athlete set a still-standing NCAA DIII championship record in women’s high jump. A requested speaker and published author, he is perhaps best known for his work: “What is the most direct means to achieve strength gains specific to the demands of jumping events”, as well as the popular article: “Fixing the Right Problem”. David appeared originally back on episode #58 of the podcast in its “classic” days. Curvilinear sprinting is a critical aspect of sport movement, and is also becoming more popular in training, and for good reason. Lateral and rotational aspects of movement are not only critical for sport, but also engage a greater fullness of the body in a training environment. On today’s podcast, David goes into the defining elements of curvilinear sprinting, and what this means, not only for track and field high jump, but athletic movements in general. He also gets into the importance of observing and coaching athletic movement from a 3D perspective, and gives ideas on how to do so, as well as the evolution that technology is making in that direction. Today’s podcast gives us a wonderful perspective on a more complete picture of athletic movement and performance. Today’s episode is brought to you by Lost Empire Herbs, TeamBuildr and the Plyomat. For 15% off your Lost Empire Herbs order, head to lostempireherbs.com/justfly. To try Pine Pollen for free (just pay for shipping), head to: justflypinepollen.com. The Plyomat is a functional, intuitive, and affordable contact mat for jump and plyometric training and testing. Check out the Plyomat at www.plyomat.net TeamBuildr is an online software for coaches and trainers. I’ve continued to hear great things about the Teambuildr platform, and whether you are looking for an in-house training portal or an online training hub, be sure to check out Teambuildr training software. View more podcast episodes at the podcast homepage. Timestamps and Main Points 2:51- High jump as a transition point for analyzing curvilinear running 8:03- Transitioning from linear to curvilinear running mechanics 10:35- The challenges of turning in sports 13:06- Unique demands of running a high jump curve 18:13- The importance of running the curve correctly 22:53- Benefits of three-dimensional movement in sports 26:29- The role of coaches in developing athletes' skills 29:09- Changing perspective for better coaching results 34:10- Overreacting to foot alignment and rotation 36:52- Mechanical gestures in high jumping vs other sports 42:24- Different ways to train 3D 47:50- Common mistakes in initiating a curve 54:45- Biomechanics lab and motion analysis Dave Kerin Quotes (00:00:15) "I describe the pelvis as a bowl of Jello. And you know how Jello tends to jiggle, how calmly non vibrational, how steady state can I bring that bowl of Jello to the moment?" - Dave Kerin (00:07:44) "The analogy would be the figure skater at the big finish when they start spinning and they've extend their arms and as they draw into the center line or the long axis of the body, they accelerate. So it's not linear acceleration in the traditional sense, yet you are increasing velocity of the plant by leaning on angular momentum." - Dave Kerin (00:18:15) "If you tell the average kid or the average coach, they say you got to speed up in the curve. Well, the kid stands upright and goes to linear sprint mechanics to accelerate. But then they've lost lean, they've lost centripetal, they've lost the benefits of running the curve. So if you run the curve correctly, that's where you get that last 10% while bringing the requisite rotations from backward lean to forward lean, lateral lean to vertical, you create bar rotation and rotation back to the bar, and it gives you more efficient bar." - Dave Kerin (00:37:06) "The efficiency is the key. And why did high jump become inefficient? Well, I think there's a lot of cases we're talking about free play and kids not learning change of direction without coach driven instruction." - Dave Kerin (00:45:10) "More isn't better. Better is better." - Dave Kerin (00:47:31) "The effective methodology to initiate a curve is outside leg separation from the center of mass, lateral pressure in the form of friction force, and then the reaction is the center of mass is redirected. You don't lean to create lean. You don't turn to redirect the center of mass." - Dave Kerin Transcript About Dave Kerin Dave Kerin is the USATF chair of men’s development, and also chair for men’s and women’s high jump. His time has coincided with a resurgence in the event. Dave’s coaching career began with 14 years at the HS level followed by 14 years of collegiate coaching where an athlete set a still-standing NCAA DIII championship record in women’s high jump. A requested speaker and published author, he is perhaps best known for his work: “What is the most direct means to achieve strength gains specific to the demands of jumping events”. He also presented that topic at the 2008 USATF SuperClinic