I didn't start working out until I was in my late 30s (and wasn't skating at that time). I've numerous sk8 related injuries (right ankle, left knee, both wrists) that limit both my skating AND my working out, e.g., I can't bench heavy (even with a spot) due to weak wrists, can't squat (rack) heavy due to left knee and heavy calf raises are gone since I fucked my ankle last April.
If I'm going to the gym, I stick to one muscle group per day, 7 days a week, every few weeks I break it up and do two muscle groups a day - push pull, back/chest, arms/abs, legs/shoulders for three days, then the next three same thing but different exercises (or different part of the same group, rear delts, traps, etc.), 7th days are the 'forgotten muscle groups' + abs and calves again.
Lately due to work slowing down, I've frozen my gym membership and do bodyweight stuff down at the beach (rings, bars, etc.,) or at home with kettle bells and medicine balls and ride about 15 miles a day on my bike the days I don't skate and sometimes hike in the AM, work, skate in the PM...and just starting lap swimming at the college near me (cheap and hot chicks
now that it's warm and bright early.
Obviously working out hard and skating hard don't go hand in hand, one will have both a - and + impact on one another...if you do a good leg day, you'll be shot for 3 days to skate and if you kill it a day or two skating, leg day is going to be rough.
I've always been super lean so for me, at fucking 45, it's maintaining while being cut/ripped and not bulky as I enjoy too much running, skating, hiking, whatever, over bro gainz.
That said, if I wasn't [perpetually] injured from decades of skating (and just aches and pains of getting older) I'd be able to lift heavy and have more mass.
Squats are king for legs, hell I've always done 'air squats' (thanks to McGill in FP future primitive or chin (?)) as warmups.
Creatine, glutamin and BCAAs, multi vita and protein.