Watch Tennis Star Caroline Wozniacki Push a 535-Pound Sled With Ease

Tennis star Caroline Wozniacki went all beast mode on her birthday, pushing a sled with 535 pounds.

Caroline Wozniacki

Tennis Star Caroline Wozniacki celebrated her 26th birthday on Monday, but instead of taking the day off to eat cake like a normal person, she worked out.

Wozniacki, who trains with Ben Bruno, recently posted a video of herself performing a Sled Push with 535 pounds. But the weight plates were not enough. NBA free agent David Lee stood on the sled, making the exercise even more difficult. Wozniacki only weighs 128 pounds which only makes her effort more impressive.

Wozniacki uses the shoulder pads on the sled, placing the weight on her torso instead of her arms so the load challenges her glutes and quads.

RELATED: Kate Upton Pushes a 500-Pound Sled, Is an Absolute Beast

The U.S. Open Tournament is right around the corner, and Wozniacki obviously wants to be in great shape for it. She now ranks 60 in singles, but she's hoping to get back at the top where she once was.

Photo Credit: Getty Images // Thinkstock