While running in a group, some people get driven by their egoism to show superb performance even though they are unfit; eventually they are forced to taking several days off to nurse their injuries. While training with others avoid going with pace above your ability avoid being burned out, this is a sure way of saving you from running frustrations. (Scott Douglas).
Another good thing about training in a group is there will always be an advanced runner, an instructor or a coach. These are people who are experienced and have knowledge on how new comers are treated and they are capable of administering the right workout.

The good news is the sooner you understand yourself and your limits, improvement is guaranteed. Aerobic training involves understanding the running economics at personal levels, VDOT (Velocity at VO max ”v-dot-2O2-max”) (Daniel’s Running). It’s the speed of running at a given threshold. This formula dictates to the body how comfortably the body is running and the overall results, however, don’t expect instant results, there is always a buffer zone in training that takes somewhere from two weeks to a month before the actual results are realized.