Tim Howard -- LARGER THAN LIFE ... Even During Youth Soccer

Back before he became an American hero, the Team USA goalie was a big deal -- literally -- towering over his soccer teammates when he was a kid ... and TMZ Sports has the pics.

Check out the gallery of Tim Howard's athletic journey over the years ... from dominating in youth soccer leagues to leading his high school basketball team to glory in New Jersey.

Oh, and here's a shocker -- he was picked as "Most Athletic" at his high school.