Hello everyone,

Right now, I am trying to gain more weight from muscles (not fat) because I have a rugby tournament coming up in 3 weeks. I am currently concentrated more on efficiency from muscles rather than aesthetics.

What are the important muscle groups that helps in rugby (in terms of strength)? What is a fast way to gain muscular strength in 3 weeks?

I play a forward in rugby, I am in the middle of the scrum. I am considered a running forward (full back) rather than a tackling focused forward (line backer).

I am currently 14 years old. I am 178 cm (around 5"10 or 5"9) and I weigh 87 kg (around 190 pounds).

After the rugby tournament, I would also like to continue working on my muscular strength.

Once again, aesthetics is not priority, however, it is a want.
Adding further details here:

I eat a Centrum every day. I drink plenty of water. Because I'm in high school, I only get around 5 – 6 hours of sleep. I do what every teenager does, 30 minutes of active exercise. In my case, its football.

I'm not much of a cardio fan. My 100m speed is 15 seconds. 40 yards its 5.7 seconds.

My diet is aggregated. I eat plentiful and smart.

I been the same weight for the past 4-5yrs, im 17yrs old and weight about 98lbs. Im trying to gain weight , also want that weight to focus on the breast size and butt im a 34B. My mother and sister are both big breasted so i know mine can get bigger. I have a small body frame I am 5'2 tall. I cant seem to follow regualr gain weight diets cuz i get full really fast so everytime time im hungry every couple hours i grabe a healthy snack such as a granola bar or if i want a a meal, i make spagahetti or eat chicken. Ive also been chewing my food alot more till its like soup and eating more slowly, i just started this the 10th of october so i know it hasnt been that long but if i keep doing this, should my breasts and butt size get bigger? (I also do exercise and work out every now in then n gym) P.S. Is it true your breasts can get bigger if you eat b4 you go to sleep and sleep without your bra on? Just a rumor i heard, My goal weight is 110-115lbs. I want to increase breasts/ butt size!