How does the tennis pro stay in tip-top shape? Lots of squats, lunges, and burpees. Williams shared the 15-minute bodyweight workout she created with comedian Kevin Hart (he's not just funny, he's super fit) on the Nike+ Training Club app.

We wish the app showed Williams doing the moves herself—the videos use fitness models—but it's still a fast-paced workout that will get you to break a sweat. Here’s a preview of the warm-up. Download the app to see all the moves (including burpees, of course) that help keep Williams at the top of her game.

Perform the following at a high intensity for 20 seconds each, resting 10 seconds in-between:

  • Bodyweight Squats
  • Heel Kicks
  • A-Skips
  • Lateral Hip-Openers
  • Sprint to Backpedal
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