Lance Armstrong and his girlfriend, Anna Hansen, have welcomed their first child together. Their bouncing baby boy was born on June 4 and weighs 7 pounds, 5 ounces and is 20 inches long. The Tour de France champ took to Twitter to make the announcement. "Wassup, world? My name is Max Armstrong and I just arrived," Lance posted on his twitter.com page. "My mommy is healthy and so am I!" Lance, who dated singer Sheryl Crow for three years, also has three children - Luke and twins Isabelle and Grace - with ex-wife Kristin.