Objective To compare strength training, aqua-fitness, and aerobic exercise programs to discern the differences in the benefits achieved by each of the activities in older people. Design Double-blind randomized trial. Setting Controlled clinical environment. Participants 108 people: 54 female paired with a male of the same age (average age of 65.5 ± 5.6 years). Interventions Three exercise programs (aqua-fitness, aerobic exercise, and strength training) for six months. Main Outcome Measures Body Mass Index, Senior Fitness Test (which evaluated functional fitness), and the SF-12 Health Survey. Results Men showed greater positive changes in the aerobic exercise group for general self-perceived mental health, leg strength, and flexibility of legs and arms. The largest improvements in overall self-perceived physical health and upper limb strength were in the men of the strength training group. The women participants in the strength training group obtained greater benefits, especially in self-perceived mental and physical health and in the strength of the four limbs. Conclusions To maximise benefits, older people, in general, may want to consider participating in aerobic activity. Furthermore, older women would benefit greatly, both emotionally and physically, from exercise that includes strength training.