I’m 5’8 and 175lbs and I work out hard 4 to 5 days a week. I wasn’t blessed with the genetics to become some huge mass of muscle. I’m taking about 100 grams of protein a day mixed with some glutamine powder. I’m gaining some muscle but not much weight as far as muscle goes. Should I increase the amount of protein I take in? With my relatively small frame I know I’m fighting genetics but there must be something in my diet or supplements that I’m missing out on. Any suggestions would help. Thx.
You should increase the amount of everything you take in. Eat lots & lots of everything.
Total protein consumption should be at least 1.5 x bodyweight if not closer 2x.
You need to learn a whole lot about how to eat. Start with the Massive Eating articles at T-mag, then the Diet Manifesto, then the Missing Ingredient article and finally read the article called 'foods that make you look good nekid." That should keep you busy for a while and stop you from eating like a little girl. 
My two cents, for what it’s worth. First of all depending on your body fat 175 lbs can be pretty good for 5’8 (read what Chris Shugart and Cy Willson write about looking like a pro bodybuilder and being the next Ronnie Coleman in ‘Things we learned’). In fact from what I hear my guess would be that most women would prefer you at 175 with under 10% BF than at 220 (maybe I should have read that ‘ideal guy’ post recently). Whatever. Diet seems of course the obvious thing to change. But it does not have to be the answer to all questions. You may also have to give your central nervous system more time to recover, i.e. you may want to try working out less frequently, or with lower volume or less intensity. Experiment and keep a good protocol of what your doing. Try something like the POW diet - i.e. find out how much you have to eat to really gain, say, 1 pound every week (you may decide to choose a different selection of food than in the original POW). Learn how your body responds to various changes and you will likely end up with something that works for you (then write a book about it and claim it’s the only real way to train :))
Even though I’m not sure this pertains to you being 5’8" and 175lbs (sounds like a decent weight), you might want to read the article entitled “The Skinny Bastard Diet.” It’s a good motivational read. Also I would be taking in much more than 100g of protein.
Oh man, this is the kinda post that you don’t even know where to begin…search for “SBSG (Scrawny Bastard Support Group)” in the subject search and read that thread…everything you need is basically in there, read massive eating and Testosterone unleashed also and you will have all the basics you need. If you are too lazy to do this than there is no way you are going to eat enough to get bigger. Good Luck (even though luck is not a factor here…its do or don’t do) ~PorchDawg
how are you training?
how much and how well are you eating?
working out 4 to 5 days a week to put on some muscle if your not a competetive bodybuilder seems a bit much to me. Why don’t you try working out 3-4 times a week for around 40 minutes. Pick a compound lowerbody or whole body exercise(squat, deadlift, lunge, snatch, clean, overhead squat, podium deadlifts, good mornings, etc.) and pick 1 or 2 compound upper body exercises (chins, bench, incline press, shoulder press, rows, yates rows, pully rows to neck, dips, pushups, etc.) Vary your rep and set protcols every 3-4 weeks. One week do something like 2 sets of each exercise, 8-12 reps, 90 seconds rest between sets. Then move to 4 sets of each exercise 4-6 reps, 2 minutes rest.
try to eat a lot of unprocessed food in small meals, 4-6 times per day. don’t gorge yourself, just eat until you’re full. don’t snack on junk food.
try to get a decent nights sleep most of the week. don’t party too hard, instead of getting ridiclously drunk just have a few drinks.