Christer - NYC - Personal Fitness Training - New York City, New York - Personal Trainer

This exercise is just one of many that can be done on the stability ball. It's really effective to strengthen several muscles groups at once while at the same developing core strength and better stability.

I am seen also doing a standard crunch on the stability ball. This is great for developing the abdominal muscles that can be seen on the body as well as the deep inner core muscles that are not seen but yet very important for balance and strength