The SPEED-POWER-EXPLOSIVE class, puts a strong emphasis on first step quickness, change of direction speed and power output. with a combination of explosive movements this course is great for pre-season sport conditioning. Sand is a excellent training source for improving speed, agility and explosive power. It provides a constant resistance that challenges multiple muscles, helping to make you faster and more explosive. The constant movement of sand under your feet engages small stabilizer muscles that improve balance and is great for injury prevention training.