I am a very slow highschool sophomore who has been running for a year. I run 30-40MPW and am following the Jack Daniels 800m plan this track season.
My PRs are
61
2:24
5:30
19:00
in the 400,800,1600, and 5k. Whenever I try to increase my mileage past 40 I feel like crap and have to sandbag all my workouts. I am still trying to slowly build up to 70ish MPW for XC season. I am also slightly overweight. I am 5'9 and 165. I have a very muscular build, but there is still a lot of fat I could lose. I could at least get down to 145 by losing purely fat. How much would a 20 pound loss help my times? Would I go from being bad to average? If I lost 20 pounds would I be able to go under 5:10 for a mile? Also would losing weight help me handle mileage better? I assume if I weighed 20 pounds less there would be a lot less pounding on my joints from running and it would be much easier to increase mileage.