Flex your muscles. The Bowflex 3.1 bench transforms any space into a personal free weight fitness center. With four adjustable positions, it allows for over 30 different exercises so you can build strength and tone-up in the convenience of your home. From Bowflex. As always, please consult your personal physician before beginning any diet or exercise program. Take a realistic approach: If you work consistently and follow the program, you maximize your results.