Off the top of my head from exercise and physiology 101 - everyone without a mitochondria disorder and other disabilities simply gets better at endurance sports

Off the top of my head from exercise and physiology 101 - everyone without a mitochondria disorder and other disabilities simply gets better at endurance sports to the limit of their ability, resistance to injury at the particular sport and time invested - which can take years. The limit on ability for short term power to weight (sprinting) is much easier to reach because most people do not have that much sprint ability, there's a component that can be attributed to genetics for any ability but the human body is generally made for endurance sports and getting better at it (the adaptations such as increased blood plasma, better ability to utilize O2, increased mitochondrial density, increased capillary density, heart stroke volume, etc) and only some of us are cut out to really excel for sprinting events (there are some adaptations for sprint that work against endurance and vice versa ala muscle adaptation, also the main energy pathway for sprinting is anaerobic which can be trained but it's much quicker to find your personal limits at a particular sport ).