This document discusses factors that influence the energy expenditure of jogging and running. It covers topics such as the difference between jogging and running in terms of speed and aerobic demands. It also discusses how running economy, stride length, air resistance, and other factors can impact the caloric cost and oxygen uptake of running at different speeds. The optimum combination of stride length and frequency depends on the individual and their running style. Overcoming air resistance accounts for 3-9% of the total energy requirement of running.