Running mechanics are also important. Posture, head position, arm movements, etc.
You easily waste much needed energy if you are not running correctly.
This.
And as corny as it sounds unless you have a coach, or really good friend, you should record yourself on a treadmill to evaluate your form.
Make sure you have no tension in your body. A lot of people run with clenched fists or a clenched jaw, or clinching their elbows and/shoulders. That might be fine if your playing football and anticipating getting hit or tackled. if youre just running and jogging and are all clenched up you're wasting energy. Loose fingers, hands, elbow, shoulders, neck, back straight, everything relaxed. Shoulders low.
Unfortunately. A Lil 2 min video ain't gonna cut it. You might be on point when you're fresh. But a few miles in or 45+ minutes in that's when your form may deteriorate as your mind starts telling you to quit and your body starts compensating. So it's weird to record yourself at times but necessary.