Read the text below: THE HUMAN ODOMETER. HOW FAR CAN WE RUN? With a good wind, the best of health, and an immortal mindset how far could someone run in a lifetime? TLDR: 2,384,112 km (). That’s 90 times around the world. Here are my workings: D = Days Able to run M = Max distance per day D*M = Total lifetime distance This basic equation is simple, yet those two factors represent multiple variables that cut into life, possibility, and sheer opportunity cost. Days Able to Run Taking a generous lifespan of 81 years there are 29,565 days in a lifetime. Even the best among us will concede it is not possible to run every day. [...] Even in laboratory conditions there will be times at the start and end of life when it’s not possible to run. Combining this with an expectation of education and we can discount the first 16 years, leaving 23,725 days. […] Injury and recovery cut into this total. Because this is a maxim I am assuming peak possible health. While novices carry higher injury rates, a Dutch study found that even experienced runners received an average of 4.11 injuries per 1000 hours. The good news is that ultra-marathoners get off lightly in the injury room — the American College of Sports Medicine found 95% of injuries were minor in nature and mostly due to skin-related disorders (74.3%). Even taking a best-case scenario, the greatest athlete running continuously can chalk off an average of 2 days per month for injury. These days will have a higher instance in the earlier and twilight years of the runner’s lifetime. This leaves 22,165 days. […] Finally, there should be some consideration that runners take rest days, even at the peak of their careers. Paula Radcliff, the fastest female marathoner of her generation, took one day a week. As a maxim, let’s quarter that, discounting one day every month. Leaving 21,436 days of active running. […] Com base