However, a recent study from Israel's Wingate Institute in Netanya indicates that women who frequently swim laps have greater leg bone mass than women who don't swim at all.
www.hydrofit.com/home/hyf/smartlist_40/choreography_library.html for a great resource regarding swimming with simple graphics and great search options. The information on this site can help you to put together a good aquatic exercise routine. You can specify shallow or deep water, exercise focus, and various types of equipment, and/or a combination of these. Print off your results, pop them in a plastic sleeve, and take them to poolside!