TREND RADAR: Stars Get Dressed To Sweat In The Hottest New Gear

How do our famous friends stay in such great shape? The hit the gym, just like us! When we saw Lo Bosworth kicking butt at the Muscle Milk Fitness Retreat on Wednesday, looking cute in her Under Armour burnout T and Under Armour Girls’ HeatGear Capri, we thought it would be a good opportunity to take a look inside of the locker room and find out how the stars dress to sweat.

Jessica Biel hit the gym in NYC, wearing a totally luxe Monrow Zip-Up hoody in dark grey with black capris and kicks. How much did the slim-fitting sweatshirt set her back? $212!

Katy Perry is absolutely obsessed with PH8 leggings, which are part of the sporty, slim-fitting and frugally priced line from Bebe. The workout fanatic has sported various colors and styles of the chic workout gear, as has Whitney Port (remember those brightly patterned hot pants?) and Jenna Dewan. 

Amanda Seyfried has been spinning her way to success in THE GIRLS Tummy Control pants, which feature the Blu-Tec Control System. Constructed out of a trademarked fabric, they are said to slim, shape and contour the body in all of the right places. Whitney Port also rocks the simple and slendering leggings.