Rethinking Osteoarthritis Management: Synergistic Effects of Chronoexercise, Circadian Rhythm, and Chondroprotective Agents.

Osteoarthritis (OA) is a chronic and debilitating joint disease characterized by progressive cartilage degeneration for which no definitive cure exists. Conventional management approaches often rely on fragmented and poorly coordinated pharmacological and non-pharmacological interventions that are inconsistently applied throughout the disease course. Persistent controversies regarding the clinical efficacy of chondroprotective agents, frequently highlighted by pharmacovigilance agencies, underscore the need for a structured evidence-based approach. Emerging evidence suggests that synchronizing pharmacotherapy and exercise regimens with circadian biology may optimize therapeutic outcomes by addressing early pathological processes, including low-grade inflammation, oxidative stress, and matrix degradation. Recognizing the influence of the chondrocyte clock on these processes, this study proposes a 'prototype' for a novel framework that leverages the circadian rhythm-aligned administration of traditional chondroprotective agents along with tailored, accessible exercise protocols to mitigate cartilage breakdown and support joint function. In addition, this model-based framework emphasizes the interdependence between cartilage chronobiology and time-of-day-dependent responses to exercise, where strategically timed joint activity enhances nutrient and waste exchange, mitigates mitochondrial dysfunction, supports cellular metabolism, and promotes tissue maintenance, whereas nighttime rest promotes cartilage rehydration and repair. This time-sensitive, comprehensive approach aims to slow OA progression, reduce structural damage, and delay invasive procedures, particularly in weight-bearing joints such as the knee and hip. However, significant challenges remain, including inter-individual variability in circadian rhythms, a lack of reliable biomarkers for pharmacotherapeutic monitoring, and limited clinical evidence supporting chronoexercise protocols. Future large-scale, longitudinal trials are critical to evaluate the efficacy and scalability of this rational integrative strategy, paving the way for a new era in OA management.