To sum it up, you need to try and stick to lean cut red meats, beans, starchy vegetables, and heavy breads(feel free to spread something yummy on the bread too). Be sure to eat three- five-- a big breakfast if you can. If you snack(which I suggest) then make sure its a granola bar or something to that effect. Trail mix is really good too.
Drink milks, juices, sports drinks, milkshakes or smoothies are good too. Cut out caffefine if you can.
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I originally wrote this for help gaining weight, however I think this is good for gaining muscle as well. Pretty much just eat a good amount of protein and you're good with muscle.
I really suggest you work on a variety of things during your workouts. Don't spend one day doing one thing. You've already got your weights out so work your back muscles when you do your arms, Or work one PART of your leg one day and another part of your leg another day.
You limbs are made of just one muscle. You can work your quads one day and your butt and calves another and still be safe! I'll write my workout down when I get to work and show you what my trainer gives me to illistrate it.
If you're not comfortable with that remember that slow and controlled lifting is the most effective. You're not powerlifting so things don't need to be fast unless you're doing cleans to a bench or another anaarobic lift. Just go slowly and you'll easily be able to lift for an hour.