I currently average about 30 mpw over five days. I do one long run and one speed workout per week, the rest are easy. In the past, my average pace on easy and/or long runs has been around 8:50-9:00. For the past few weeks I have not been looking at my Garmin during my long/easy runs and have been surprised to see that my average pace in now closer to 8:30. Part of me thinks this is too fast but I am not breathing hard and I can talk to my running friends (conversational pace).  Is 8:30ish now my new "easy" pace or should I force myself to slow down? Also, I can now run more miles without feeling as fatigued as I did in the past.  Is this just a natural progress to building more miles? I feel like my body is telling me go more, but my brain is telling my to not overdo it. Currently I am running 5 and 10ks and am training for another HM. I have read that you should add no more than 10% of your weekly mileage a week. Any advice? Sorry to be so wordy...

I think you are just getting faster, Jack.  You are faster than me and my easy pace is in the 8:35-9:00 range, so it doesn't surprise me that you are running 8:30 as your easy pace now.

Yep - you're getting faster! I felt similar right after I ran my first half. That easy pace used to be around 9:50, now it's 9:20 or so.

Easy is a subjective measure of effort, not a pace. On any given day the pace for an easy effort can vary quite a bit from the average. Your experience is one of the reasons why some of us urge runners not to rely so much on Garmins or a watch, especially in races. As for the 10% mileage increase, that is for a single week over week increase and is more a simple guideline. Only experience will tell you whether you need to limit increases to less or can go beyond that. Don't make the mistake that many canned programs do and increase several weeks in a row. Take time, perhaps 2-3 weeks or more, for adapting to new mileage levels before another increase.

+2 on George's comment. Increase, get used to it for a couple of weeks, then increase again. Don't be afraid to back off for a week once in a while. My work schedule demands it, but I think it's good to give the body a break from time to time.

I learn so much from the very experienced runners on here. Based on some of the responses to the OP's question I have a related question:

Should I not worry about my pace on training runs, and only effort? For example, yesterday my calves were bothering me, so I dropped my pace considerably, but the effort was equal to my normal effort even though the pace was less. And another day a run is feeling really easy and I will see my pace is a bit faster than my usual "easy" pace. Is that normal/okay?

Good topic.  Thanks for starting it.

My easy runs can vary from 8:35 to about 8:50 depending on how I feel.  There are days however, that a 5 mile run at 8:20 feels easy.  I have come to learn though that on those days it was just a good run, not necessarily an easy one.  If that makes sense?

I judge the slow end of an easy run by how hard it is to run it.  By that I mean it takes effort for me to run 9:22 for 20 miles, whereas 8:50 for the same distance comes naturally (easy).

Thanks, everyone... it all makes sense.  I know easy is not a pace, but that's just how I refer to it. Thanks for the info and advice on adding mileage.

RMTB: I am NOT faster than you!