Diet, water, rest/sleep, and changing up your routine every couple mmonths or so is critical. By my senior yr in high school (17yrs old) I was able to bench 315 (3 plates) which at the time I thought was cool, Its not. Do not hurt yourself. Genetics is also a factor you can't escape, but discipline can off set this.

When I took my 3 mo vacation to Parris Island, I went in a chisled 220lb god and came out a spindly 177lbs pencil necked dweeb. I had to start all over again, but it came right back.