Let me start by clearing up something I feel is a misunderstanding about the Zone. Most everyone familiar with the Zone knows that it's based on 40-30-30 nutrition, i.e. getting 40% of calories from carbohydrates, 30% from protein and 30% from fat. But, as a point most people miss, this is only a starting point. 40-30-30 is what a majority of people will do well on. But as everyone is different in regards to genetics and activity level this equation needs to be modified and fine-tuned. I personally have to have a little more carbs than 40%, some else may need a lot less. So if you've ever heard anyone say that they've not done well on it, know that they actually didn't follow it correctly because you tailor make this diet for yourself.
The main focus of the Zone diet is the control of your body's hormones; control your hormone levels and you control how well your body operates. The diet accomplishes this through tight regulation of insulin levels. Insulin regulates blood sugar and is also the 'fat storage' hormone. Raising insulin too high tells your body to store fat AND tells it to not release fat. A double blow. How do you raise insulin levels too high? Several ways: by eating too much protein or carbs, by eating 'bad' carbs, having to much caffeine, eating carbs by themselves (without protein and fat).
Insulin also affects other hormone levels in your body. To build muscle and lose fat you must maintain good levels of two hormones: growth hormone and testosterone. Human growth hormone (HGH) is the most powerful fat-burning hormone in your body and it also allows your body to build new muscle. When you raise insulin, however, you inhibit the release of HGH from your pituitary gland.
If you want to combine diet an exercise maximally there are four windows of opportunity for applying this diet to enhance hormone release.
1) About 30-45 minutes before exercise eat a Zone snack to 'set the stage' for hormone release and to have good energy.
2) You actually release HGH 15 to 30 minutes after you work out. This is the best time to eat a Zone favorable snack or meal. It will keep insulin levels low in order to max HGH release. Yet many people have a sports drink right after they work out. This will jack your insulin levels and inhibit the release.
3) 2 hours after the end of any exercise you need to eat a large Zone meal as insulin levels continue to return to baseline.
4) Another time that HGH is released in the body is during stage 3 and 4 sleep just prior to REM sleep. This is the time in which your body repairs itself for the next day. You should always have a Zone snack before bed. This insures that your blood sugar and insulin levels remain stable. If you don't your blood sugar could drop to low and you might go into Fasting Hypoglycemia (low blood sugar due to not eating). This could not only give you insomnia but will inhibit HGH release.
Insulin levels also control testosterone. While raising insulin levels increase the amount of testosterone in females (not desirable) it will decrease the amount in males (obviously not desirable). You want to work out with your testosterone levels high. If you eat incorrectly and spike your insulin levels you will lower your testosterone level. Also, testosterone is higher in the morning (before 3pm) so it's best to work out during the day than at night.
Aside from controlling these two hormones there is another reason why the Zone diet will improve your gains: the free radical. You've probably heard of free radicals. A free radical is the name for a molecule that has an unpaired electron. Free radicals are necessary for life as they are needed in producing cellular energy from food, defending you against infections, and balancing hormones so that your body can maintain communications.
This sounds fine until you realize that excess free radicals are very damaging. Any free radical not immediately used in a chemical reaction will steal another electron from some other molecule to make itself whole again. This forms another free radical and a chain reaction is started. Many negative things happen in the body because of this, such as the oxidation of fats, proteins and DNA. To put it another way, excess free radicals destroy proteins, fats, organs, and MUSCLE!
So how are excess free radicals formed? One main reason is overeating. It's been known for 60 years that eating a calorie restricted diet (eating only what you need and no more) prolongs life span. This is the reason why. So all that extra protein that you're told you should eat to build muscle only creates free radicals that destroy your body, causes you to have a greater recovery time and even shortens your life. Say it isn't so!
On the Zone you find out exactly how much food you need to eat and that is all you eat. This is based on your size, amount of body fat, and activity level (you do need more as a lifter, but you need to find out exactly how much more). Also, on this diet you focus on foods that contain antioxidants (vitamins C and E) that kill off excessive free radicals.
Read the book and follow it strictly. The Zone diet will not only give you the best gains, it will also trim you down. Yes, you can do both at the same time.