POWER WALKING,SPEED WALKING,THE ACT,WALKING WITH,SPEED,UPPER,THE NATURAL,RANGE,THE WALKING,GAIT,QUALIFY,RUNNING,ONE FOOT,MUST,BE IN,CONTACT,THE GROUND,AT ALL,TIMES,WALKING,FORMAL,DEFINITION,EXAMPLE,KENNETH H COOPER,ALTERNATIVE,MODERATE EXERCISE,REGIME,INSTANCE,MAXIMUM HEART RATE,HRMAX,ALMOST,EFFICIENT,LESS,IMPACT,JOINTS,EXAGGERATED,ARM,SWING,CONFUSED,RACEWALKING,RULES,DEFINE,COUNTS,FAST,OLYMPIC,LEVEL,EVENT,FITWALKING,REEVES,STEVE POWER,BOBBS MERRILL,LIVESTRONG COM,