'A stability ball is a type of ball commonly used in physical therapy and athletic training. Correctly measure a stability ball with help from a personal trainer, aqua therapist and swim coach in this free video clip.  Expert: Bridget McGrath Bio: Bridget McGrath is a certified personal trainer as well as an aqua therapist and swim coach with more than 10 years of experience. Filmmaker: David Kumpe  Series Description: Working out doesn\'t need to require thousands of dollars in expensive gym equipment. Get a complete workout sans machines with help from a personal trainer, aqua therapist and swim coach in this free video series.' 

Tags: personal trainer , stability ball , quick exercises , weight training , Quick And Easy , abdominal exercises , easy exercises , exercise training , workout help , without machines

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