What causes soreness?

I havent worked out in a long time. Obivously i was going to be sore. But what actually causes the soreness? The muscles beeing broken down for the first time in a long time or soemthing like that?

Also i have a question as to my sorta- diet

Day 1.
-breakfast. Snickers Mathon Protien bar. and a bottle of water (26g of protien)
-lunch. Turkey Sandwish / whitebread  with .5 teaspoon of mayo. 1 Banana and some baked french fries. A peach .Bottle of water.
Snack1.Protien bar (26 grams of protien) water
=Workout
-Orange juice with 50 grams of protien
-dinner Grilled chicken breast with baked potato with a teaspoon of butter

I weigh about 200lbs.. is that an ok meal for a day?? that was the first day i started to work out, thats why there is so much protien.. but am i going in the right direction?




 

For the diet...what is your goal?
 
Soreness is from built up acids in the muscle...just an indicator that your level of fitness in relation to removing waste products is not developed yet...it will though.
 
5-6 meals a day!

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 I dont really have a set goal. Just Gain muscle and lose weigh. But im not going hardcore. It is impossible for me to eat right 6 times a day. altho im gonna try.  I just want to eat foods that will help me build muscle. And thats for the info.

 It is impossible for me to eat right 6 times a day. altho im gonna try.

 
Well, that is what it takes to optimally gain muscle.  Whenever you go more than 3 hours without a "snack" you start breaking down muscle...
 
You do what you can.
 
Meal 1 have real food - Cereal/Milk/Whey/Nuts/Fruit
Meal 2 have what you eat for breakfast now--the bar+ celery/broccoli/ etc
Meal 3 Lunch
Meal 4 the bar+ celery/broccoli/etc
Meal 5:
---Pre workout 1 large orange and 1/2 the protein (BCAAs here would be good too)
---Post workout 1 large banana and 1/2 the protein (BCAAs here would be good too)
Meal 6 Dinner
 

 I dont really have a set goal.

I don't care what your goal is..but you need to decide what you want.  I read that you want more muscle.  Thats Fine!  How about gaining 2-4 pounds each month of lean muscle?
 
I am going to tell you that the bars are NOT a good source of food. Poor quality, poor ingredients.  But you do the best you can !
 
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Alright thanks alot