Even the ancient Greeks used performance enhancers in the form of leaden and stone hand weights called halteres, which weighed between four and twenty pounds. The proof is plain to see on many ancient Greek urns depicting Olympic athletes clutching these objects as they compete in the long jump.
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The windmilling motions of the arms are also fast forward rotations. Making some parts of the body rotate faster causes other parts of the body to rotate more slowly to compensate.