Alright everyone. I'm sorry to bother you w/ the newb question, but I figured this would be the best place to find the answer. I am just starting to get into weight training and I need a little advice. I have just assumed I am an ectomorph, so I have started looking into books and training routines based on that assumption, but I am starting to wonder. After reading, and looking on-line, I have tried to find the weight of ecto's in my height range, and they have been smaller than I am. I am 5'10" and 156lbs. I have only trained for about 3 weeks, so I am not in great shape, but I am not chubby or too soft either. I have always been about this weight, except when I was playing sports in high school when I weighed about 145-148 and had VERY little body fat (I miss those abs) but I never lifted weights either. The ecto examples I have found at my height though are like 115-135, so I don't know if they are just extreme examples or if I am not as small as I thought. So am I an Ecto, or an Ecto-Meso hybrid or something? I just want to figure this out so I can tailor a fitness routine for myself from the beginning, and not train for 6 months only to find I am not making the gains I could on another routine. Any help/advice you can lend would be most appreciated. Thank you so much.

I don't think you should base your diet and fitness routine around what body type you as of yet. That is something that comes into play more after you've been working out for 6 months or so (maybe a little earlier). To begin though, it would be good of you to post your AGE, DIET, and WORKOUT ROUTINE, so that the more qualified people of this forum can give you a quality answer instead of just a shot in the dark explanation.

If what you want is a general answer though, I can give you this.
1. If you are trying to get leaner while preserving the muscle mass you have, lift heavy with low reps but more sets. Eat plenty of protein 1-1.5 grams per pound of lean body mass and try to limit your carb intake to just before and after your workouts. Also, do more cardio. Getting lean is all about burning more calories in a day that you ingest.

2. If you want to gain size, eat eat eat lots of proteins and carbs, get plenty of rest, and use medium weights with a medium rep range (I can't believe I just told someone to do this), and try to hit each muscle group 2x a week to limit atrophy.

Sorry about that, you're right. I'm 29, I haven't started any sort of diet yet, I was looking into body type to find the best option there. I eat average-fairly healthy right now. Fruits, veggies, and lean meats, but I also hit up the junk food, but I have just put a stop to that. I'm looking to add lean mass, and strength. I don't need to loose weight really; I'm pretty trim 31"-32" waist. I'm mainly concerned with adding muscle, but I want it to be lean muscle. I don't want to just add bulk and look soft. That would interfere w/ sports.