Workout Focus: Endurance, Lower Body Intensity: Intense! You need: A timer, water. Warm Up: 20 x half squats | 20 x walking lunges | 20 x good mornings | arm circles forward and backward for 20s each | 20  x wall push-ups … or try the Super-Quick Warmup routine. Stability Training: Single calf raises – 2 sets of 20 […]