What aspects of health are being affected? How are they being affected for each girl?

If it's a smaller child or infant, place one on the middle of the chest and on the child's back. (if it is a bigger child with enough room for two, place one on the upper right/your left of the chest, and one on the lower left/your right) the pads should never touch each other. 

Force and balance. you get agility from balance and the force you use, and leverage can only be attained by using the force to get it. hope that