The 15 + 5 workout to build muscle and burn fat

The holidays are right around the corner, and you know what that means: no time for anything. But don’t let your six-pack disappear only to be replaced by a flabby gut.

The secret? Working more efficiently.

In this video, Ryan Heffernan, a certified personal trainer at FOCUS NYC, demonstrates a 20-minute workout to keep off total-body fat.

Directions

Workout 1: Set a timer for 15 minutes, and complete as many rounds as possible.

Workout 2: Set a timer for five minutes, and complete round one as quickly as possible. Attempt to complete round two—faster.