IJRAP International Journal of Research in Ayurveda and Pharmacy 2277-4343 Moksha Publishing House 10.7897/2277-4343.17283 A REVIEW ON TRIVIDH BALA AND FUNCTIONAL RESERVE IN AGING: AN INTEGRATIVE AYURVEDIC AND BIOMEDICAL PERSPECTIVE Kumari Deeksha * MB Gaur 11 -0001 220 224 Aging is characterized by a gradual decline in the body__ampersandsign#39;s capacity to withstand physiological stressors. In classical Ayurveda, this capacity is described as Bala (strength/vitality), divided into three types — Sahaja, Kalaja, and Yuktikrita — collectively known as Trividh Bala. Contemporary biomedicine conceptualizes a similar phenomenon as functional (physiological) reserve, the surplus capacity of organs and systems allowing resilience against stress and delaying frailty. This integrative review elucidates the conceptual parallels between Trividh Bala and functional reserve in aging, mapping Sahaja Bala (innate constitutional strength) to innate, constitutionally endowed reserve; Kalaja Bala (age- and season-modulated strength) to age- and season-modulated reserve decline; and Yuktikrita Bala (acquired/lifestyle-dependent strength) to lifestyle-acquired reserve plasticity. It further examines the pathophysiology of reserve depletion, assessment modalities from both Ayurveda and biomedicine, and evidence-based interventions including Rasayana (rejuvenation) therapies, exercise regimens, and chronobiological adaptations aimed at preserving functional capacity and promoting healthy longevity. Trividh Bala Sahaja Bala Kalaja Bala Yuktikrita Bala Functional Reserve Aging Biomedical Geroscience