The Fat-Burning Question: Run or Cycle?

A study published this year in the International Journal of Sport Nutrition & Exercise Metabolism examined the different types of fuel the body uses when running or cycling. Researchers observed that running tended to burn more fat than cycling when performed at the same intensity, but the cause isn’t entirely known. In other studies, scientists speculated that running uses more large muscle groups than cycling; still other data suggest that running recruits more slow-twitch fibers, which tend to burn more fat than the fast-twitch variety used preferentially in cycling.