When considering effort level over pace, it’s important to understand how you feel when you’re running. A lack of this understanding is why many people race poorly and don’t get the best race performance.
Pace and performance on any given day will be affected by so many factors, some within and some out of your control. Here are a few; terrain, hills, hydration levels, sleep, weather, altitude, energy levels and fatigue from training. All of these factors and others can affect you and, if you’re particularly unlucky, all of these factors could affect you at the same time. Instead of slogging yourself to hit a specific pace, and running too hard, we suggest running to perceived effort or to specific heart rate zones, if you know them (but don’t worry about that too much at the moment!)
If you train too hard you are more likely to injure yourself, by pushing your body too hard.