Zoning out during your cardio sesh and no longer seeing results? A brick may be your fix. Triathletes use these workouts (which layer more than one activity) to boost their endurance, but they offer other benefits too.
"Varying your motion and intensity forces your body to continue adjusting, which keeps calorie burn high," says Adam Zucco, an Ironman coach and owner of TrainingBible Coaching in Chicago. Plus, switching from one activity to another keeps you engaged. Use Zucco's routine below on machines, or take it outside, and discover how a twofer can help you get fit in a flash.