A solitary run with a good playlist is worlds differentthan running alongside others, seeing people you don't know happily cheer you on from the sidelines, and, many times, having a purpose to your run that's bigger than getting a workout in.
In other words, a workout where you start out with fat - burning hormones and keep them throughout is a very differentworkoutthan one where you switch from fat - burning hormones to sugar - burning hormones and eventually back again.