Strength + Weight gain tips

weightlifting doesnt work if you dont eat.... Record what you eat for a week and then add 500 calories/day. Make sure you are getting at least 100g of proetien per day

You should really focus on gaining weight because at your height that seems like an unhealthy weight. Eat ice cream or peanut butter before you go to bed and perhaps cut back the mileage. You will probably run a lot better if you gain at least 10 maybe even 20 pounds. But your weight is at a dangerously low level and your health is more important than running. Most high schoolers amd collegiate obsess with running but by the time they're 30 they probably dont care about running anymore.

Start eating breakfast if you don't already. If you aren't really a breakfast person try out brunch/2 lunches. In high school I didn't really eat breakfast a lot but I would either 1) pack 2 lunches, one to eat at 10am and one to eat at noon or 2) pack food to eat at 10am and eat school lunch at noon. The brunch/first lunch I ate wasn't really all ate at 10am but more of spread out over and hour or two.

I know some runners only drink water, but to add calories start drinking milk and juice. Still drink water but have some non-water beverages with your meals.

Start snacking throughout the day.

Buy some protein powder and try drinking either a regular protein shake (water/milk + powder) or by adding it to smoothies with fruit/greens/etc. Making shakes with milk instead of water will add calories. If you don't like/can't drink milk try milk substitutes (almond, soy, etc.). Drinking your calories can be an effective way to put on weight.

I'm kinda questioning how your coach isn't helping you any with your weight even after you asked him about it as 5' 10" 110 pounds is very much underweight.

I know how tough weight gain can be but it can help your running out a lot. Gaining healthy weight helped me endure (and succeed in) the meat grinder 800 program that was my high school.

Overall, I would suggest talking to a doctor/nutritionist about all of this as they are experts.

See the problem is I eat like pretty much a lot haha, in the morning I eat a bowl of cereal about 2 cups with normal 2% milk and then I'll run and then come home and probably munch on a small snack(3-5rice cakes usually) then I will just kind of munch throughout the day eating small amounts of snacks 3-4 times per day for the afternoon and for example tonight I had Ribs, with veggie stir fry and fruit salad which was a very filling meal. I guess I don't eat a ton but it's not like I am unhealthy, I am actually the fittest I have been right now(15:07 5k as of two days ago for a pre season TT). Could this be a genetic thing since both of my parents were smaller and didn't mature until college? I mean I don't think I am really a "late bloomer" but my body really hasn't developed other than a 7 inch growth spurt my freshman year.

Also it's not that easy to just grow 20 pounds in a couple of months lol, I can't really cut down mileage right now cause I am building for this years xc season where I need to show out haha

Why on earth do you think your not eating is genetic? Seriously why are you filling up on junk food like rice cakes if you want to gain weight? Get your calorie count up to a reasonable 3-4k (lets assume your running 50+ mpw) and your "genetic" problem goes away