As a celestial being, Thor is not tied down by physical limitations that are common among most humans. His Asgardian physiology imbues him with many enhanced abilities that are common among most superhumans, such as strength. In fact, following the deaths of his father and sister, Hela (Cate Blanchett), he is the strongest of his kind.
Thor’s bone, skin, and muscle tissue – which Gamora (Zoe Saldana) compares to “metal fibers” in Avengers: Infinity War – are incredibly dense, making him nearly invulnerable to almost any kind of damage – not to mention that his enhanced regenerative healing would take care of any injury he may sustain pretty quickly. His reflexes and physical movements in general are pretty quick, too, unlike his aging process. In another moment from the 2018 crossover epic, Thor mentions to Rocket Raccoon (Bradley Cooper, with mo-cap by Sean Gunn) that he is 1,500 years old and looks pretty good for it, if we are being honest here.