Click to enlarge. Image Credit: University of Tennessee, Knoxville

No matter how much we train, most of us will never be history-making athletes. But aside from years of dedication and training, what is it exactly that separates the average person from an Olympic champion? Kinesiologists from the University of Tennessee, Knoxville put together this primer on what really separates the fastest, most talented athletes in the world from those of us still training for our first 5K run. From muscle fibers to heart size, there are a handful of very real physical differences that go beyond just having a more toned body.

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