If you have worked your triceps for example and they are stiff, then 2 sleeps later you want to do chest, will it hinder the growth of your triceps because they are not fully recovered from your previous workout?
And how much bread should I be eating? Baring in mind that I am a 17 year old boy with a reasonably quick metabolism working out 3-4 times a week...Answer:
A good rule to follow would be to not work a muscle that is still feeling sore from a previous workout. Definitely let your triceps rest a little more.
Since the tricep muscle is a smaller muscle group, it's best to work your triceps with bigger muscle groups, like chest or shoulders, but do the triceps at the end of the workout.
If your triceps are still sore after a couple of days, and it is preventing you from working out, simply work around it by adjusting your workout routine, or modify your routine slightly, so that you don't have to take another day off.
How much bread? Whole wheat bread is your best option. There's no recommended amount. Just use common sense and occasionally add it to your meals. Make sure you add a variety of carbohydrates to your diet.