For the next 30 days, you'll push yourself to look and feel stronger. Each workout is totally customizable, making it great for all fitness levels. Certified personal trainer Charlee Atkins designed every 20-minute workout with beginner and advanced options. Over the next 30 days, you'll notice you can do more reps within each timeframe, which means your fitness level is increasing. You'll also likely see some muscle definition and increased energy levels. Let's finish strong!