Robert PArish played 21 seasons, longest in the NBA.
morten Anderson nfl from 86 to 08
This is a very broad question. You might want to ask who had the longest career in NBA, MLB, MLS, NFL, and NHL ext. This will tell you who had the longest career in each sport and you will then be able to see who had the longest career or ( in your words) who played sports the longest.
Robert "The Chief" Parish has the longest active NBA career with 11,611 games played over 21 seasons. Darrell Green who played 20 seasons from 1983-2002 with the Redskins.
John Stockton - 19 years with Utah Jazz
Richard Petty had the longest career.
Shaquille O'neal has 2,920 assists in his NBA career.
Zydrunas Ilgauskas has 11,601 points in his NBA career.