By RealJock Staff

This exercise provided courtesy of Billy Polson, founder and co-owner of DIAKADI Body training gym, voted best personal training gym in San Francisco by CitySearch in 2006.

Benefits
Find an open space for this fast-building leg set. Run forward and backward up and down the floor, accelerating on each lap. This is a cardio warm up, but the backward runs add some great glute and hamstring training.

Muscles Worked
Legs

Starting Position
Stand in a room with at least 40 feet of open floor in a straight line (such as an aerobics room or basketball court, or even a sidewalk), with as much space as possible in front of you. Take up a sprinter's stance, with feet staggered and upper body slightly inclined forward (see Photo 1).

Exercise

1. From the starting position, run forward, setting a swift but controlled pace and using your arms with your run. When you've gone roughly 40 feet (around 12 strides), run backwards back to your starting point, keeping the same pace going backwards that you had going forwards, but being careful not to overbalance and fall (see Photos 2 to 4).
2. Repeat the run for a set of four laps, forward and back. Accelerate on each lap, until on the last lap you are running a sprint. Be very careful going backwards; it is better to decelerate than to fall, as you risk injuring your wrists.

About Billy Polson: Billy Polson is the founder and co-owner of DIAKADI Body training gym, which was voted the best personal training gym in San Francisco by CitySearch in 2006. A competitive swimmer and triathlete in his own right, Polson has over 15 years of experience working as a coach and trainer, and was recently named by Men's Journal Magazine (December 2005) as one of the Top 100 Trainers in America.