Why your muscles aren’t building
You Have A Big EGO.
What’s the first thing you do upon entering the gym? Well, duh. Bench press, as much weight as possible, til’ failure and not a rep short. I mean, I get it. If you didn’t do this, how would everyone else in the gym know that you are strong? Look, you HAVE to set your ego aside. Building muscle is not about lifting as 
much weight as possible every set. I know, I know, that doesn’t make any sense. But total volume, tempo, time under tension and rest intervals are all incredibly important for hypertrophy (muscle growth). If you follow a strength training program, and the weight on the bar is increasing, you are going to add muscle mass. Further, strength specific training should indeed be incorporated in great muscle building programming. But hypertrophy requires a slightly different strategy. Without going on too drastic a tangent, here is a brief summary on how the two differ:
Strength
Rest Time: 2-5 minutes between sets
Rep Scheme: 1-5 reps/set
Tempo: Get that weight up!
Hypertrophy
Rest Time: 30-90 seconds between sets
Rep Scheme: 6-12 reps/set — occasional 15-18 reps/set and rare 20-25 reps/set.
Tempo: Varying the number of seconds you spend in the eccentric and concentric portions of a lift, as well as controlling pauses at the top and bottom of an exercise, can elicit great results.
No Sleep
We get it, you, Wiz Khalifa, and 50 Cent are taking over the world, one all-nighter at a time. But that doesn’t go over well for building muscle.
3 Steps: Train, eat, recover.
If we neglect even one of these three, we sacrifice progress. Why, you ask? Well, for one, Growth Hormone is produced during deep sleep. Yeah, that same stuff that juice heads inject in their veins, our bodies produce it during sleep time. However, Growth Hormone is only produced during the deep stages of sleep. That means that even if you are lying in bed 7-8 hours per night, but waking up constantly, your body isn’t producing much Growth Hormones. Focus on sleep quality. Further, getting less than 6 hours of sleep for just two weeks has been shown to decrease Testosterone by 15%. and don’t forget that stress hormone, 
Cortisol, that the body produces like crazy during sleep deprivation. Aim for a minimum of six quality hours per night to keep everything running smoothly.
You Have No Plan For Rest Times
Now, for fat loss, traditional strength training is great. Take a few minutes between sets, and really give it hell for a few reps at a time. That is the best way to retain muscle in a calorie deficit. But, if you want to pack on muscle, you need to be keeping precise rest times. Bring a stopwatch, or use the stopwatch on your phone. Gazing off at the clock won’t to work; you start to think, “Is my next set at the 12 or the 6?” And next thing we know, you have procrastinated an extra minute of rest. Stick to the rest intervals noted earlier, and be disciplined. Results shall follow.
Skipping Mobility Work, Warm Up or Both
Oh, you don’t foam roll? You don’t stretch? You don’t warm-up? Unless you are a genetic freak, you aren’t going to stay healthy long enough to add muscle. Spend 10 minutes before each workout getting warm.
Your Training Lacks Real Intensity and Focus
Scan the floor of a commercial gym, and you immediately know who isn’t building muscle. Are they watching TV? No muscle. Are they reading a book or cosmo? No muscle. Are they scrolling twitter or 
checking in on facebook? No muscle. Is this your view of the weight room? Uh oh, you’re screwed.
You need to train with intensity if you want to build muscle. Now, this doesn’t mean training to failure on every set. But it does require going hard: limited rest times, reasonably high volume, and the intangible and immeasurable X-factor, genuine focus on every rep of every set. Do whatever it takes to be intense, whether it’s the Taylor Swift Red album or Guns N’ Roses Welcome to the Jungle. Personally, I often go to a pretty dark place mentally to prepare for a set. Not only does it help me release a lot of the bad stuff, which 
does wonders for mental health, but it provides the fuel necessary to lift heavier weight for more reps than I otherwise could.
No Water
Water transports nutrients around your body, like, from your mouth to your muscles. Your level of hydration also impacts the efficiency with which you break down and absorb nutrients from food and, of course, how they are used to build muscle. Plus, if you are reading this, water is free and accessible for you. So you have no excuse to be dehydrated, ever. Unless it’s following a night of tipping back beers.
You Don’t Eat
Yep, we saved the most obvious and most true for last. There are two types of under-eaters. Under-eater #1: “I eat SO MUCH, but I can’t gain weight!” Sorry man, but you gotta eat more. Keep a food journal for 3 days, write down everything you eat and add up the calories. 99% of the time, you just need more food.
Under-eater #2: “But, if I bulk what will happen to my abs?” You, my friend, need to just get over yourself. Sometimes you sacrifice a bit of definition to build muscle. I know, intentionally masking your beautiful six-pack in favor of a calorie surplus may cause you to freak out on day 11 of the bulk and start another 
phase of fat loss. Just breathe. Rest assured, no one else cares about your abs.
Practical tips: Estimate your maintenance, eat a 500 calorie surplus, monitor your bodyweight and increase calories every few weeks if the scale isn’t moving.
For weight loss – estimate your maintenance, eat a 100-200 calorie deficit (Males on the lower end, Females on the higher end), monitor your bodyweight and increase cardio every few weeks if scale isn’t moving.