I have had two distinct stages of training in my life. In high school and college I averaged 80 to 90 mpw and ran a high 14’s 5k, sub 4:20 mile and 1:55 800. I then took a decade off where I did little to no running and lifted a lot of weights. Started up running again after the layoff and was 35 pounds over my running weight in my peak years, with more muscle and a higher body fat percentage. Now average 50 to 60 mpw and run low 17’s 5k’s.
While these two periods were very different in terms of performance and mileage, my biggest improvements in both periods came from the same things. I made the initial error of focusing mostly on increasing mileage as a guide line for improvement. Don’t get me wrong, mileage is vital and the basis for all improvment, but I feel like I put too much emphasis on running the miles without focusing on proper nutrition/weight loss and workout intensity:
-Weight loss: Dropping 5 to 10 pounds from the weight I would otherwise be at if I ran my normal mileage and ate as I felt like (i.e. no real plan or diet goals and not depriving myself of junk/alcohol) almost immediately resulted in me making a huge jump in performance in both college and after my layoff. The idea that mileage alone will keep you at your ideal weight is flawed. As someone that loves to eat and thinks about food a lot, it is difficult for me to cut back on calories. That being said, feeling hungry and cutting out as much processed food as possible makes a big difference. You won’t necessarily feel more fit, but your training paces and race times will drop. While the weight loss angle seems obvious in hindsight, I think you’d be surprised at how much and how quickly it can improve your times (assuming you’re not already stick thin).
-Intensity: Find the right balance of mileage versus intensity. I’ll preface this by saying that I’m not the obsessive/compulsive distance running type that struggles to take an off day. I tend to prefer harder efforts versus long, slow aerobic runs. I was at one time convinced that I needed to scale back my intensity in order to increase my mileage. In that mode it’s easy to follow a training plan and do the typical 2-3 hard days per week and long run without giving much thought to whether or not you are really pushing yourself. Be careful about reducing the intensity of workouts TOO much as you increase mileage. For me, the easiest ways to make sure I maintained proper intensity were to (1) run with guys that were much better than me and try to hang on (even if I faded), (2) run workouts at a pace that felt TOO hard and see how long I can last, (3) challenge myself to run hard on days where I felt like running hard, even if it was scheduled as an easy day and (4) be courageous enough to have a monumental blow up and come back and do it again the next day, week, whatever.
To summarize, get your mileage to a reasonable level for sustained improvement (probably at least 50 to 60 mpw), stop eating to hunger and make do with less and every now and then increase the intensity of your workouts above what you think you’re capable of.