Sprinting ( High Knees ) - Best ... (High)

http://www.sixpackfactory.com : High Knees or sprinting on the spot is a cardiovascular exercise that will help you to improve your cardiovascular endurance.
To perform high knees stand upright and bend your arms slightly at your sides. This movement is exactly like that of a sprinting action. Bring your knees up high towards your chest as quick as possible and combine with an alternating arm action. The key to this exercise is speed and height of the knees.
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