Participants were randomized equally into one of three groups: Group 1A received alendronate for 96 weeks; Group 1B received alendronate for 48 weeks followed by placebo for 48 weeks; Group 2 received placebo for 48 weeks followed by alendronate for 48 weeks. All three groups were followed off treatment for an additional 48 weeks. Participants also received vitamin D/calcium for the duration of the study and were asked to perform 60 minutes of weight-bearing exercise each day.