Think of this as a standing and moving leg extension. You'll need a weight sled with strap handles.

Stand with the sled about two yards in front of you while holding the handles with your arms straight at hip height. Assume a partial to mid-squat position so your thighs are at roughly a 45-degree to a 90-degree angle to the floor.

Step backward one leg after the other. Don't round your upper back at any time; keep your torso and arms straight throughout. Use a load that's neither light enough to run with nor heavy enough that you have to lean your body backward at a 45-degree angle. Find a load you can move in a smooth, deliberate manner.

It's a quad-builder, a great conditioning method, and it's also perfect if you don't have access to a weight sled.

Place a heavy weight plate on top of a towel so that it glides on the floor or a turf surface. For more of a challenge, put a set of dumbbells on top of the weight plate. This allows you to get into a neutral-grip push-up position with your hands on top of the plate.

Push the plate across the floor by driving with your legs and bringing your knees up toward your chest. Push the plate quickly across the floor, up and back, for a total of 40 to 50 yards.

Be sure to keep your elbows straight and your arms at roughly a 45-degree angle above your head. Take long strides and don't let your hips drift higher than your shoulders.