Definition of organism for English Language Learners. : 1  an individual living thing. : 2  a system with many parts that depend on each other and work together.
Figuring out how many calories you burn when running is, on a simple level, a fairly straightforward calculation. Most experts (and lots of studies) suggest that a person of average weight burns about 100 calories in a mile of running.
Running and racewalking burn more calories per mile. Running burns more calories per mile than walking, likely due to the effort of the lift phase, which raises both feet off the ground at the same time during running.