I used to run before this latest bug, like a year ago, but I hated it. My only goal was to do a sub 30 minute 5k and I trained for like 8 months with 0 progress and was so dejected I quit. I would show up, run at a 10 min pace for as long as I can, repeat. It felt like shit and I didn’t get better. My growth happened when I just ran 4.5 mph until it was the _bad kind_ of uncomfortable (this is too much stress on my shins vs my legs muscles are building lactic acid). After two weeks, I upped the pace a tiny tiny bit. I spend most of my runs fighting with myself to slow down.
The science behind it is something something aerobic base and running economy. I’m absolutely not an expert, but anecdotally I’ve never had my life improve so much in such a short amount of time by just _running slower_
Run a quarter mile at 80% of full speed, then 50%, then 80%, then 50%, etc and play with the percentages and interval lengths to push yourself.
Where is your weight at? This is another factor
Consistency is the biggest factor for improving running. Run at a pace and distance you can handle every day, then do that consistently. Every day, ideally. It doesn't matter if that's 10 minutes for 1km, just as long as you're being consistent.