Quercetin directly reverses cellular aging in tendon stem cells by blocking AKT phosphorylation, which stabilizes mitochondrial function and suppresses inflammatory SASP factor secretion via the NF-κB/NLRP3 pathway. In aged rats, a specialized hydrogel delivery system restored tendon regeneration capacity to youthful levels within eight weeks. This represents a significant advance in addressing one of aging's most problematic tissue repair failures. Tendons lose regenerative capacity with age as their stem cells become senescent and secrete inflammatory compounds that further impair healing. The ability of a widely available flavonoid to reverse this process through well-characterized longevity pathways suggests broader applications beyond tendon repair. The mechanistic clarity—targeting mitochondrial dysfunction and cellular senescence—aligns with fundamental aging biology principles. However, the rat model limitation requires human validation, and the optimal quercetin dosing remains unclear. The hydrogel delivery innovation could enable local treatment without systemic effects. This finding bridges cellular aging research with practical regenerative medicine, potentially offering hope for the millions suffering recurrent tendon injuries that worsen with age.