High Intensity Interval Training is a superior form of interval training, an exercise strategy that requires alternating periods of short intense anaerobic exercise with less-intense recovery periods. HIIT workouts are short, but they are exhausting and intense! This app includes EXTREMELY intense workouts that will build muscle, burn up thousands of calories, improve your cardio, and increase fat burning! Your Fitivity app has multiple training programs in it for HIIT and fitness! Switch between programs that were designed specifically for you! In addition to your weekly workouts, try out Fitivity BEATS! Beats is a highly engaging exercise experience that combines mixes by DJ's and super motivating trainers to push you through workouts. • Audio guidance from your personal digital trainer • Customized workouts designed for you each week. • For each workout you are provided with HD instructional videos to preview & learn training techniques. • Stream workouts online or do workouts offline. Should I upgrade to Premium? As a Premium member, you are very special to us. We’ll do whatever it takes to get you better, no matter what! A Premium subscription unlocks Fitivity’s entire collection of over 80+ apps. For any app, get access to all content. Fitivity Premium gives you access to thousands of HD videos, workouts, and weeks of sports and fitness training!