Source:amazon.comURBNFitExercise Ball$19.99Natalie MitchellThis exercise ball is perfect for anyone looking to add stability and balance training into their at-home workout regimens. Exercise balls are easily inflatable and come in a variety of sizes and colors. I have the 55-centimeter ball as I am shorter in height, so if you are taller, I would recommend sizing up. I love to do planks and hamstring curls with my feet on the curl or switch it around to do crunches with my back on the ball. You can use this exercise ball in many different types of workouts, such as pilates, weight training, or high-intensity interval training.…View more