Hey OP, you are in a very similar position to where I was when I started running at age 31. Before 2014, I was just a tennis player and would jump in a local race every once in a while . At the beginning of 2014, I became interested in running more and was consistently running low 19 5K. I didn't know anything about training and was running every run at the same "fast" speed and was constantly getting injured. My advice(and what I did).....look at your local race results, find a couple that consistently win local races and send them a message. I was lucky to find 2 guys that trained together following Daniels training program and I just did what they were doing, but at my prescribed paces. It sucked being slower than them, but with consistency I was able to put together the PR progression below and catch up to them fairly quickly and have been faster than them the past couple years now. I used to think breaking 17 was the hardest thing I'd ever do, and now I do it easily. You will see major gains after 1 solid cycle on Daniels. Just make sure you run your easy days easy; rest up for the hard days. Now I get my training from Tom "Tinman" Schwartz, but you don't need that when you are just getting started. Aside from the PRs listed with 2019, all of this has been on my own following Daniels methodology. But really it all just came down to being consistent, 1-2 workouts a week, getting a good long run in each week, recovery/easy miles at 8-9 min pace, learning as much as you can, having fun and looking forward to races and maybe making a few friends along the way.
1 Mile-
5:36 Previous PR from my 20s
5:10 (Summer '14)
4:52 (Summer '14)
5:10.92 (Summer '15)
4:38.90 (Summer '16)
4:34.76 (Summer '16)
4:35.70 (Summer '17) Market Street Mile
5K-
19:02(Spring '14)
18:49(Summer '14)
18:14(Summer '14)
17:29(Spring '15)
17:16(Spring '16)
17:10(Summer '16)
16:56(Fall '16)
16:54(Spring '17)
16:35(Fall '18) Turkey Trot
10 Mile-
61:27 (February '14)
61:31 (Spring '15)
61:31 (February '16)
58:41 (Spring '16)
57:42 (Spring '17) Mission 10 Miler
57:21 (Feb '19) Club Challenge
1/2 Marathon-
1:43 (2012)
1:22:24 (Summer '15)
1:19:54 (Summer '16)
1:20:30 (Summer '18) Frederick Running Festival
1:14:27 (Spring '19) DC Rock n Roll Half
Marathon-
3:43 (Spring '14) Just to see what 26.2 was like.
2:54:59 (Sept '18) VIA Marathon in Pennsylvania. Not all out, probably about 80% effort. Just wanted sub 3, and BQ.
Racing Boston 2019 - Expecting sub 2:40 if good weather.