Exercise

Most newer ships and some older ones have well-equipped fitness centers, many with massage, sauna, and whirlpools. An upper-deck fitness center often has a view of the sea; an inside, lower-deck health club is often dark and small unless it is equipped with an indoor pool or beauty salon.
Many ships have full-service exercise rooms with bodybuilding equipment, stationary bicycles, rowing machines, treadmills, aerobics classes, and personal fitness instruction. Some ships even have structured, cruise-length physical-fitness programs, which may include lectures on weight loss or nutrition. These often are tied in with a spa menu in the dining room.

Spas have become increasingly popular on cruises. They may have giant thalassotherapy pools (a combination Jacuzzi and massage), indoor heated swimming pools, and treatment rooms. The list of treatments may include ionotherapy, aromatherapy, hydrotherapy, and reflexology. The spas may also sell beauty products not available at home.

Sun Deck

The top deck is usually called the Sun Deck or Sports Deck. On some ships this is where you'll find the pool or whirlpool; on others it is dedicated to volleyball, table tennis, shuffleboard, and other sports. A number of ships have paddle-tennis courts, and a few have golf driving ranges. (Skeet shooting is fast becoming a thing of the past on cruise ships; when available it's usually offered at the stern of a lower deck.) Often, at twilight or after the sun goes down, the Sun Deck is used for dancing, barbecues, limbo contests, or other social activities.

Pools

All but the smallest ships have at least one pool, some of them elaborate affairs with water slides or retractable roofs; hot tubs and whirlpools are quite common.

Pools may be filled with fresh or salt water; some ships have one of each. While in port or during rough weather, the pools are usually emptied or covered with canvas. Many are too narrow or too short to allow swimmers more than a few strokes in any direction; none have diving boards, and not all are heated. Often there are no lifeguards. Wading pools are sometimes provided for small children.