Our 45-55 cm Anti-Burst Yoga Balance Ball is recommended for shorter women: under 5'6'' tall. Our Pilates balls can withstand 600 pounds of pressure and are extra thick, so they won't pop or burst. Use them in conjunction with floor exercises to strengthen the core. Use under the feet in push ups for the ab workout of a lifetime! Or, improve posture while toning small muscles in the abdomen by using this resistance ball to replace your office chair! For shipping purposes, our Swiss balls come deflated so you can get them through your door. The kids will love to play around on them, too. Please note that the red yoga ball tends to fade into a dark pink color once it is blown up.