Conversely there are probably runners whose fitness and training might put them on a 3:05ish time but running in a pace group brings them a mental boost to get them down to 3:00 that they couldn’t run on their own.

It’s the Boston Qualifying time for men age 18-34 and a very good benchmark. It will also be a massive pace group you can run in. Aiming for 2:57 you might be running on your own the whole time and if your only goal is BQ then may as well run for 3:00. On the other side, those with fitness and training that “should” put them on for a 3:03 pace will dig ultra deep mentally and physically to stay with the 3:00 pace group.

The normal distribution of times that should exist centred on 3:00 collapses onto the marker.

3 hours is Boston Qualifying time for men age 18-34 and generally a very good benchmark so a popular target time.