Objective: To examine the effects of an exercise program and an enriched food regimen on physical functioning of frail elderly persons. Design: A 17-week randomized, placebo-controlled trial. Setting: Community. Participants: One hundred fifty-seven independently living frail elderly (mean age, 78.7 +/- 5.6yr). Intervention: Thirty-nine subjects participated in a twice weekly group exercise designed to improve daily functioning; 39 subjects daily ate foods enriched with vitamins and minerals (at 25%-100% of the recommended daily allowances); 42 subjects exercised and ate enriched foods; and 37 subjects served as controls. Nonexercising groups followed a social program; nonsupplement groups received the same food products without the micronutrients. Main Outcome Measures: Functional performance based on 6 performance tests, physical fitness based on 7 fitness tests, and disabilities based on the self-reported ability to perform 16 daily activities. Results: Performance sum scores were significantly enhanced in trained (+8%) compared with nontrained subjects (-8%) (difference in change: 1.9 points, p < .001, adjusted for baseline scores). Fitness sum scores were significantly enhanced as well (+3% in trained vs -2% in nontrained) (difference in change: 0.9 points, p = .05, adjusted for baseline scores). No exercise effects on the disability score were observed. Consumption of enriched products did not affect performance, fitness, or disability scores. Conclusion: Our comprehensive exercise program, designed for widespread applicability, enhanced physical performance acid fitness in a population of frail elderly. Daily consumption of micronutrient enriched foods showed no functional benefits within 17 weeks. (C) 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.