Discover Why Trainers Recommend Large Exercise Balls for Working Out. Using a yoga ball for exercise will improve the strength of your core. Since stability balls for exercise are unstable, you have to use your bodyàcore strength to remain balanced, which in turn improves proprioception, posture, flexibility and body alignment. Workout Ball for Abs These sturdy workout balls for exercise come in 45, 55, 65, 75 and big 85 cm diameters, 55cm exercise ball, 65cm exercise ball and 75cm exercise ball (or 30 inch exercise ball) being the most popular. You can choose from multiple colors: black, blue, silver, teal, aqua, pink, red, purple and green. With this balance ball for exercise, you can get trim and toned by exercising ab, back, glutes, hips, arms and more-aking it the ideal full-body tool. Use as a balance ball chair (medicine ball chair) at your desk or office, for rehab, or during maternity as a yoga ball for pregnancy. Use the extra large yoga ball for stretching, toning, balancing or various resistance exercises. The small yoga ball works great as a replacement to your home office chair, since as a yoga ball office chair, it is soft, and engages the core. Yoga Ball Chair for Office. Swiss balls for exercise have found their way into the office as an office ball chair, turning sitting into a way to build your core strength. Burn more calories with the desk ball chair by performing active sitting. Pregnancy ball exercise for Labor. The big ball ab ball has become an essential birth ball for pregnancy and labor. Recommended by obstetricians, midwives and doulas to help your baby into an optimal fetal position. Get your exercise ball for pregnancy and help reduce aches and pains caused by PGP and SPD. Increase your odds of a safer and faster birth with a labor ball. Made to be burst resistant and easy to inflate with included yoga ball pump. Get your excercise ball, maternity ball or sitting ball today and add to your exercise balls & accessories!