“I would never do this move on land,” said Shannon Mooney, who was exercising next to me as we thrust our hips forward and back to the beat of the music blaring in the warm pool room Thursday night at Frances Meadows Aquatic Center. I smiled in agreement and tried to keep pace with instructor Zandrea Stephens who was moving quickly on the pool deck and encouraging myself and 14 other women in the center’s “Aqua Zumba” class. I joined the class as part of The Times’ series about experiencing exercise classes first-hand.