Due to repeated, high-impact use, the bones in a tennis players racket arms are 20% thicker and contain more bone mineral than their other arm! This dramatic growth helps them cope with intense workouts and reduces the risk of breaking.

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Secrets of the Human Body (2017)
The human body is the most sophisticated organism on earth. It's a scientific marvel and much about it remains a mystery. Secrets of the Human Body uses cutting-edge graphics to effectively peel back the skin and reveal the surprisingly beautiful biological processes that keep us alive.

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