Get a top-quality product for a top-quality workout. The Obsidian Surge Water Rower will keep your workouts engaging and challenging. Studies have indicated rowing can work up to 85% of the bodys muscular system without the joint impact of other conventional cardio exercises. This in turn results in higher calorie expenditure in a shorter period of time. Elevate your workout and be more efficient with the Obsidian Surge Water Rower.