You want to gain weight? Wish I had that problem. More fat! Butter on everything! Heavy cream! Olive oil everywhere!

It seems pretty decent assuming your workouts are intense enough. Personally I like to go a little higher on the protein and reserve higher carb intake for days when the intensity hits 10, as in plyo, weights and stretching for up to 2 hours, lower fat on those days and HFHPLC on off days. It's getting closer to summer so I've been shifting towards LC and my lifts are intense but shorter to maintain lean mass while cutting fat. For me any dip in protein intake results in loss of strength and I assume lean mass but I'm just going off of the mirror, scale and my lifts.

In my opinion that isn't enough. I have been eating 3500 for a while now and I am still not gaining, I am actually losing as a matter of fact. I have no idea if my activity levels are that high or if I have some underlying medical condition, but it is surely activity levels. I work on my feet all day, and then play soccer in the afternoon.

More protein. Lift heavier. Get a good nights sleep EVERY night.

I'm trying to gain 15 lbs by the first of the year. I'm attempting to do it with a serious Ketogenic cycling diet with a few extremely taxing lifting sessions and carb re-feed days twice a week. I'm attempting to keep it 100% Paleo, which is very difficult for the carb portions.

With that said, there is a certain amount of "hacking" you can do with manipulation of nutrient-timing. The macros are far less important day-to-day as long as over the long-term, they remain consistent. With that said, it's a rough balance when you are trying to gain muscle, minimize fat, hit certain macros and also keep things "regular" in-terms of other health aspects. I, for one, can't stand digestive distress. Even on Paleo, you can cause some of that if you are eating massive quantities of starchy and non-starchy veggies and a ton of protein.

Two pieces of advice.

1. Vary your protein sources. I find that eating a wide variety of protein in a variety of ways (some lean, some fatty, some with added fats, etc...) gives the body a much better efficiency. Overloading on the same 2 or 3 things every day gets boring and causes me some digestive problems. It also makes it possible for someone consuming a ton of protein for muscle growth (I'm upwards of 250 grams a day) much easier when the flavors vary.

2. Vary your veggie sources AND cooking methods. While my carbohydrates are mainly sweet potatoes, squashes, brussel sprouts, broccoli, cauliflower, cabbage and carrots, simply because I love the taste of them, consuming them in the same form day after day can be problematic. For instance, a high-carb day I'll try to hit nearly 300 grams, which is very difficult if that means eating 5 baked sweet potatoes. I find that if I boil one until it's extremely soft and throw that in a protein shake, and then the next time I eat one it's a par-baked potato, it's much easier to "stomach" than just a huge batch of steamed veggies. Some days I'll eat 8 oz of carrots, half-stewed and the other half raw. Variance is a good thing.

I have done a couple mass gains in the past year and tracked my food. I am also 5'8" at 131-133( varies day to day). I gained 8-9 pounds(1lb or so was probably fat) in two months doing high protein(47%) and high fat(53%). I was getting a about 200g of protein a day (1.5g protein/lb) and the rest was fat and grass fed butter. I was eating on average 3700cal a day, maybe having a fasting day to up my appetite once every two weeks. If you really wanna put on muscle and strength, go for at the very least 3,000 cals; that is what i started at and increased by 250-500cals once eating that amount of food become rather easy to accomplish. Tracked all my food (amount, recipe, calories, grams of protein, and grams of fat) as well, my training (heavy power lifting, high volume work, with conditioning work once in a while.) I had virtually no carbs except from what was in protein powder and coconut milk, but I have never really been much of a carb eater, so it wasn't a big deal. The only thing I would change with my approach is to add a hefty amount of veggies, I didn't eat too much of them, but I'm not much of a vegetable guy myself. I love meat. The one thing I made sure to do was to listen to my body, if I was tired or lethargic one day, I would rest extensively, drink a lot of water and maybe eat a couple mashed potatoes. Also, workouts in the morning before i eat my meals (usually fuel with butter coffee), allowed me to eat 2,000cal breakfasts. The more work or exercise you do a day, the more calories you should eat, just feel it out. I hope this helps.