Filming first from a tiny basement in Prague, and eventually settling in Los Angeles, Zuzka Light has single-handedly ushered in the YouTube fitness revolution. Viewers love Light for her short, ferociously effective workouts and her in-the-trenches, never-give-up positive attitude—and she’s racked up more than half a billion views to prove it.

Now, finally, comes 15 Minutes to Fit, Light’s hotly anticipated debut, with a 30-day fitness plan guaranteed to burn fat and build ripped muscles. Based on innovative high-intensity interval training, the workouts in 15 Minutes to Fit are designed to be done anywhere, anytime (no fancy gym equipment necessary), in just 15 minutes a day. This book takes the guesswork out of the workout, providing: