I started running about a year ago. I had always hated the idea of it. I started anyway because I needed some exercise and running was the only thing I could practically fit in. No gym, no kit faff, no booking anything. Put shoes on, leave house.
For the first six months I did it badly. Every run was as fast as I could, chasing PBs on Strava. I felt sick at the end of every run and kept picking up niggling injuries. The times improved for a while, then stopped. That wall was what made me actually do some reading. This is basically everything I wish I knew when I started.
Kit
Get fitted for proper running shoes. Runners Need do a free fitting, they put you on a treadmill, look at your gait, and recommend shoes that suit how you actually run. A decent pair is around £80-90. This is the single most important thing you can do to avoid injuries before you have even started. Skip the carbon-plated stuff, it is not for you yet, probably not ever.
Get a watch that tracks heart rate. You will need it for the next bit. A second-hand Garmin Forerunner 55 on eBay is about £80 and does everything you need. If you already have a smartwatch that tracks heart rate, that is fine.
That’s all you need (assuming you have shorts and a t-shirt).
Run slowly. Much more slowly than you think.
ALL of your running should be in “zone 2”, which means a heart rate low enough that you could hold a conversation. It feels absurdly slow at first. People will overtake you walking briskly. You will feel like you are not really exercising.
This is the point. Slow running is low impact, builds aerobic fitness, and does not break you. Once I started running almost entirely in zone 2, the injuries stopped and I got fitter rather than more battered and could run more often. Zone 2 is hard to judge by feel when you start out, which is why the watch matters, you will go too fast without realising.
Set up a “slow run” workout on your watch that alerts you when you go above zone 2, and stick to it. The watch will work out your zone 2 from your age, you do not need to calculate anything. Start at fifteen minutes and add time gradually. Try and get out a couple of times a week. There is no need to do anything more than this for at least the first six months.
Technique
Technique is important to avoid injuries.
Hips forward, shoulders back, arms held up roughly like you are holding drumsticks. Lean forward slightly. Light, bouncy steps, landing on the ball of your foot or flat, not on your heel. Keep strides short. If you want to go faster, take more steps rather than longer ones. Try to land evenly on both sides.
Pay attention to your form. It will improve with practice. If your form starts falling apart, slow down or walk. Running with broken technique is how you get injured.
Strength
Strength training is important, but at least for now, you do not need a gym programme. Lunges are the best thing you can do for the time invested, they strengthen the muscles around the knee and hip which is where most running injuries come from. They also fit naturally onto the end of a run. I do sixty lunges as a warm-down at the end of each run, three sets of ten on each side.
Why this works
The whole point is to keep running, get fitter, and enjoy it. Every recommendation here is really about not getting injured, because if you avoid injuries you run more often, and if you run more often you get fitter. You will naturally get faster over time without trying to. If you push for speed early you will get hurt and stop. It will take time though, there is no shortcut.
A year of going slowly has done more for my fitness than the six months of going hard ever did. I can now run 10k literally without breaking a sweat.
I am now, regrettably, a running bore.