I am a sophomore in high school (15 y/o) and I am just wondering how important weight is for running. Currently I am 5' 7.5" (~171.5 cm) and fluctuate between 118.5 - 121.5 lbs (53.75 - 55 kg). I am concerned because on one hand, I feel like maintaining or losing more weight could stunt my growth and possibly affect my future performance, and I hear it can increase risk of injury (I am running 50 mpw on average). On the other hand I am scared that gaining weight will slow me down for the season (my first race is in a little over a week). Any insight?
Note: I eat pretty healthy (almost no processed food; mostly fruits, veggies, nuts, and whole grains, but some white meat; 2400-3000 Cal/day) and I take a daily multivitamin.