How do I begin and end my workouts? I use the lunge matrix. It is a multi- directional exercise that I use for my warm-up, for strengthening, for power, and for my cool down. It is a multi-purpose exercise that strengthens your legs and core, opens up your hips, and protects your back. My trainer, Juan Ruiz-Tagle, and I take you through the lunge matrix in the video below. I look forward to your comments after you have tried this starting routine.