I could not do that. When I go to the gym, I work out really hard, and it's not healthy do to that every day. Whenever I try to do that, I will fall ill quite soon (maybe due to overtraining) - everybody has her own upper limit of stress the body can cope with, and exercise is stress by definition - no pain, no gain! :)
If that's how you're training, then it isn't necessarily the volume/intensity but your diet that's holding you back. I train as an advanced Crossfit athlete 5 days a week and it's very intense exercise!
Diet is more important than most people think! If you are truly training hard and you don't have a hard time getting your last few bites per meal down, then you're not eating enough.
At peak training (for me) an example diet would look like this:
Morning: 6 eggs (free-range), 4 strips of bacon (only happy pigs), two apples, one pear, and a little cup of almond butter.
Pre-lunch snack: half a bag of cashews and/or a few Kind Bars and 48 grams of protein in a shake.
Lunch: usually something I've cooked the night before, like Coconut Curry, Chili, steak or chicken. I always eat bacon to get my fat - some of these dishes will have been made with it, if I'm just eating steak I'll have 3-4 slices of bacon with it. To get my carbohydrates I fall back on fruits and sweet-potatoes. I'll have two sweet-potatoes and an apple, usually, with the above type of meal.
Pre-dinner snack: 48 grams of protein in a shake.
Dinner: similar to lunch, it will be some paleo meal that has been cooking in the Crock Pot all day or something I already made with enormous amounts of protein and fat in it. Again I get a lot of my calories from sweet-potatos and fruit so for dinner I'll usually eat a lot of berries, pears, sweet-potato fries, &c...
This type of diet is 100% gluten free and 100% refined sugar free and HFCS free; I also try to eat organic/free-range where I can. There are some instances where it just gets too expensive for me and have to buy some veggies/fruits that are not organic.
Cool! You are right, I have recently found out that I don't eat enough carbohydrates. I've been sticking to Tim Ferriss' advice too closely (haven't experimented, which was my mistake) and have fallen into starvation mode. Maybe I'll up the carbohydrates even more.
If you're getting ill, then you're (probably) missing something in your diet.
After working out hard enough for a few months, I used to get an injury (muscle strains)... then take the rest of the season off to let it heal. It would happen every time I tried it.
At first I tried reducing my exercise... that worked.
Then I started paying more attention to my diet. Turns out, I would often only eat 45-60g of protein a day (not a huge fan of meat).
Fixed that.. now I can exercise hard every single day without any injuries.
My experience was similar. When I started Crossfit I was following my small portion eating habits and didn't really focus on getting enough protein, fat, or carbs (my thinking at the time was carbs and fat were bad, I had no distinction about WHICH ones were bad).
There was a point where I was complaining about feeling tired all the time and my coach asked me what my diet was like. I told him. He scolded me.
Ever since then I've noticed HOW MUCH diet truly affects my athletic performance and my recovery.