I am 19, I workout 5 days a week with aerobic exercise at least 3 times week. I was wondering how many calories I should take in? I've been counting them with myfitnesspal but it suggests I only take in 1,600. I've read around and many of the sites I've looked at recommend I take my weight (124) x 17 to get my calorie intake. I just don't want to take in too many but also don't want to fall below the line and end up burning muscle. Any help would be appreciated!