On the same day that she completed the Nautica Malibu Triathlon in Malibu, CA, a surprisingly energized and glammed-up Jennifer Lopez attended the 40th birthday party of her hubby Marc Anthony in New York City.

Looking stunning as usual, Jennifer wore an elegant white gown with an empire-waist. The superstar turned super-athlete walked hand-in-hand with her husband-singer Marc, who looked sophisticated with a three-piece suit and traditional bow-tie.

The couple that bi-coastally supports one another, stays together!

Also at the star-studded event, actress Brooke Shields and her husband Chris Henchy, actress Leah Remini, and burlesque performer Dita Von Teese!

Click here to read all about Jennifer's finish-line triumph!