Speed Intervals: Engaging Your Core…Releasing Your Legs

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I was watching a young woman doing 400m repeats run on the track this week. She looked like a good runner and I guessed she probably ran for the UNCA track team and was doing some “off-season” summer training. The biggest piece of her running form that stood out to me was that she had an anterior pelvic tilt and as she ran faster her lower back arched, bringing her upper body more vertical. She had good knee-bend, a nice circular stride, and landed in a midfoot strike, so her lower half was in good working order. But because her upper body was arching up into a vertical position, I knew she was using her legs way more than she needed to.

I turned to my running partner and said, “If that girl made one small adjustment to her upper body, I’ll bet she could knock 3 seconds off her 400m interval times and not notice any increase in effort.

I rarely, if ever, walk up to someone and offer running advice. But, since she looked very focused on doing well, I approached her as she finished one of her intervals. When asked, she told me she was indeed on the track team, at which point I asked her if I could offer her a suggestion that would make her run faster yet easier.

She agreed and I told her what I saw in her form and that her upper body just needed to get more with the program. When I asked her if she ever did crunches, she said, “Sure, all the time.” Then, I told her that although she may have a strong set of core muscles, she’s not taking full advantage of them when she arches her lower back and holds her torso vertical. In order to fully engage her core, I told her she needs to hold her upper body in what feels like a crunch while she’s running, so that it brings her shoulders more forward, a little ahead of her hips. This would throw her into a slight lean and allow her to relax her legs. So, the only focus I gave her was to sit up in her “chair” (I demonstrated sitting forward in a chair and holding your shoulders in a forward position) and to simultaneously let go of her legs, completely… and see what happens.

As she started her last interval I could immediately see the difference in her upper body and she looked much more fluid and very relaxed. When she finished her lap I saw her check her split. She looked up at me and gave me a wide grin and two-thumbs-up. As she trotted over to me I asked her how it felt, to which she responded, “It felt really easy and it was my fastest interval of the day!”

I just had to ask her, “How much faster was it?”

“Three seconds!”

If she took three seconds off a 400m interval, imagine how much she could take off a 5k or 10k run. Experiment with this in your own running and see how it feels. The main points to remember are: Keep your chin down (lead with your forehead), sit up in your chair, and LET GO of your legs (allow them to go almost limp) as you fall forward.


Posted in Technique

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