Elliptical walkers are low-impact and provide great cardio for your body. Use these machines efficiently with help from a certified fitness expert in this free video. Expert: Bridget McGrath Contact: www.tahoept.com Bio: Certified personal trainer Bridget McGrath also has more than 10 years of experience as an aqua therapist and swim coach. Filmmaker: David Kumpe Series Description: Cardio and aerobic exercise are the fastest way to increase heart strength and burn fat. Get started with this exercise using guidelines from a certified fitness instructor in this free video.