I am very skinny. My metabolism does not let me put on much fat at all. If I'm not working out, my appetite slows down and I eat smaller meals. What I eat seems to make no difference - I can eat tons of sweets and junk foods but it has no noticeable affect on my weight. My assumption is anything extra goes out the other end cause my body does not store fat.
I also have very dramatic energy loss if I don't eat. If I'm hungry and I don't eat, I start to get very hungry, then adrenaline kicks in and I'm good for a little while longer, and then I go off the deep end and primary goal #1 is food. You don't want to be around me when I get that far, so I just tend to constantly eat
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My maintenance weight when I am not working out is about 140 lbs, at 6'2" and 25 years old. Call it what you will but I find it very difficult to put on weight. I almost never gain weight in fat, and I need to eat A LOT to maintain muscle mass. If I'm getting lots of exercise, and especially if I'm lifting, I'll put on about 10 lbs of muscle. The most I've ever weighed is 155.
I'm sure I could put on more muscle weight if I tried hard enough. But I think that would entail 1) quitting the aerobic sports I like (skiing, cycling, martial arts, tennis) and 2) eating enough that it would be a chore. When I was 155 I was lifting 3x a week and eating 3,300 calories per day, including as much protein as I could handle. Yes I was counting accurately, and did so for about a month. I would use those massive calorie/protein shakes whenever I could. The problem is eating when you're not hungry just plain sucks - you do it if you have to, but I'd put it in the 'con' category.
For now I have just decided to be skinny, healthy and fit
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