While watching people run it is not uncommon to see athletes run with a bounce or spring in their step/stride. Vertical oscillation is the up and down movement that occurs with each stride. While everyone will "bounce" slightly while they run, the goal is to reduce this as much as possible. Too much bounce wastes energy and decreases the distance forward with each stride.
You can help reduce your vertical oscillation by trying not to lift your knee so much when running. In other words, all your energy should be behind you, not in front of you. Fellow USAT Coach, Kelly Wisolik does a great job at explaining this:
"Lifting versus pushing is the concept that is better described as 'muscling versus springing,'" he said. "In distance running, an athlete does not want to 'lift.' Lifting means 'launching.' This involves a lot of muscular use as it requires power and strength to lift and launch forward.
"It's good for power running like football and basketball players and track sprinters. But this extra energy expenditure is not advantageous for distance runners and triathletes. Lifting pulls the chest up and not only uses more muscles but more oxygen too! Lifting occurs when the stretch-shortening cycle is not effectively being employed during the running stride.
"Pushing is the idea of pushing off the extended leg during the running stride. Pushing is an effective use of the tendons and momentum. Dropping the knee, leaning forward and springing from extension engages the natural reaction of the Golgi Tendon. This conserves muscles and oxygen and therefore is good for distance runners and triathletes. This is the concept of 'dab and push forward,' 'drop and spring' and 'lean and push' which reduces power loss unlike 'lift and pull.'"
While the description above is well written, sometimes is best to just pretend like you have a glass of water (or wine) on the top of your head and you're trying not to let it spill.
Many athletes find it invaluable to seek out a local triathlon coach to take a look at your form (swim, bike and/or run) and help correct it. Clinics offered by local run/bike shops and triathlon clubs are another option. Whether you're looking to improve your economy and make you a little faster or if you're mostly concerned with injury prevention, working on proper run form is well worth the effort.
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