Full title: Deer Valley. Pool Exercise. A positive aspect of American seniors is their realisation that the correct exercise is not only useful to prolong active life but is also fun. The Palm Ridge Recreation Centre Deer Valley Arizona is the latest in facilities. Persons aged 55 and above pay $500 for a years program. Many members are over eighty years of age. The water aerobics class - three times a week never has less than eighty members.