Swiss Balls are large balls that are anti-burst so that you can put your entire body weight onto them. They need to be the right size for you depending on what you will be using them for. They do come in a variety of sizes usually from 55cm in diameter to around 80cms.
Swiss Balls are great for core exercises that can help to provide support for your back and pelvis. They can also be used to help mobilise parts of your body such as your knees, hips and lower and upper back. A lot of complexity can be added using a Swiss ball making a simple exercise much harder and challenging for the core. They can also be used as a chair for short periods of time which can also help to increase the stability around your spine and are great to use for support while performing exercises while pregnant. Doing exercises on a ball while you are pregnant can also help to provide support to your pelvic floor muscles while you are exercising.