I started as a 30 year old ex-distance runner of 17 years with probably not great genetics (I was a 2:32 marathon runner).
Since the end of November I've gained 15lbs of lean mass, almost 20 if I'm carbed up going from 140-45 to 160-65 at sub 10% and 5'6', so I was already a little more muscular than most distance runners to begin with.
Benching started out doing 135 for 5 reps...last time I did BB Bench (a number of weeks ago) I did 200 for 2 at the end of 4 sets. Doing close grip each week and did 195 for 2 reps at the end of 4 sets last time. DB Bench was 50 for 10 reps, now it's 70-75.
Squat went from 135 uneasy, not deep, 15 reps to 185 for 10 now and also front squating 185 for 5.
Deadlift went from having trouble with 135 for 5 reps to 285 for 2 reps.
Could barely do 3 good pullups before, now I can do at least 10-15 with perfect form.
It's like anything...eat right, train right. You'll get stronger and bigger, but not as strong or big if you started as a teen. Test production is going to likely be lower due to age but other than that just focus on the task at hand.