Can you tell me a way to figure out my basic metabolism?

Why is it I can always run a greater distance on a track than I can on a treadmill? On a track, I can run five or six miles, but on a treadmill, I can only go a maximum of three or four, then I tucker out. Is it because I get more bored on a treadmill, or is there a more physical explanation?

I am a second year Nutrition student and have a question about protein and endurance athletes. Why are their protein requirements greater than they are for resistance athletes? Is it because the muscle glycogen stores get depleted over a long period of time with intense exercise? If so, should they consume more carbohydrates than resistance athletes, with a low glycemic index prior to their workout?

I have started spinning and I absolutely love it. Currently doing it about 3 times per week. My boyfriend says that spinning will cause permanent damage to my female genitalia, such as damaging the nerves, leading to reduced sensitivity and ultimately impeding my enjoyment of sex. I always wear the appropriate padded shorts. Is this true or not?

I am currently trying to revise my eating habits to eat less often (I'm a throughout the day snacker, and normally don't eat meals). Is it okay to replace cravings or "boredom eating" with herbal teas? I was told that tea is a no calorie drink, and yet it fills me up when I'm hungry. I have started to replace most of my cravings with tea now, so that I actually eat a lot less than before. Is tea healthy for you if it is no caffeine, herbal, and I use honey to sweeten it? I am not used to drinking much of anything in the day and am fairly slim, so could the extra water intake have any weight gaining effects on me? Could this be a healthy diet?

My soccer coach is suggesting we eat bananas at half-time of our soccer game to rebuild our energy for the second half. I understand that bananas are a very good source of energy, among other things. I don't see any detriment to this idea, but my question is this: Does the consumption of bananas result in an immediate energy boost? I have always been led to believe that food must be digested through the system before the body realizes the benefits, and that usually takes several hours. Can you enlighten me?

Is egg powder an effective egg substitute for protein?