India, Sept. 2 -- Who says getting older means slowing down? At 68, Portugal-based runner Jose Aguia is challenging that notion with his remarkable speed, stamina and disciplined approach to fitness. With more than 1 million followers on Instagram, Aguia regularly gives his audience a glimpse into his active lifestyle, sharing high-speed running sessions, workout clips and healthy eating habits. (Also read: 44-year-old fitness coach shares simple exercises that help her look '15 years younger' )

What makes his fitness journey even more inspiring is that he did not start running in his youth. Aguia says he took up running after the age of 50 and has since turned it into a serious pursuit, reportedly winning more than 200 trophies. His Ins...