The video thumbnail image shows an orange illustration of a cross-country skier.

Watch: How cross-country skiers move uphill

The classical diagonal stride is one technique used in cross-country skiing.
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    The competition that would become March Madness dates back to the NCAA's first Division I men's basketball tournament in 1939.
  • Encyclopædia Britannica, Inc.; thumbnail © kovop58/Shutterstock.com
    The first Olympic Games consisted of a singular event: a footrace.
  • A “white-collar boxing” match, London. White-collar boxing is a form of amateur boxing that emerged in the late 20th century. It features men and women fighters who are typically employed in white-collar jobs.