Supplement and Exercise Effects on Stationary Immunity and Health in Older Adults

The goal of this clinical trial is to learn whether a natural-origin nutritional supplement, combined with a moderate-intensity functional exercise program, can improve seasonal immunity, perceived health, and oxidative stress in older adults. The study will also assess the safety of this combined intervention. The main questions it aims to answer are: * Does the combination of supplementation and exercise enhance immune function during seasonal changes? * Does it reduce oxidative stress and improve perceived health and functional capacity? Researchers will compare a supplement to a placebo. All participants will follow the same supervised functional exercise program. Participants will: * Take a daily nutritional supplement for 6 months. * Attend two weekly functional exercise sessions (60 minutes each), including mobility, explosive strength, and coordination/agility training. * Complete three assessments (before, midway, and after the intervention) including blood tests, physical function evaluations, and quality of life questionnaires.