So you've been training for a while now and yet your body has not changed shape at all, your biceps are still stringy, your chest is flat, and your legs aren't going to be seeing the light of day until they have grown more.
There must be a reason for this lack of growth? Actually, there could be multiple reasons why you are not gaining muscle.
This article will look at the most common reasons, and help you to overcome them.
Reason #1. You aren't eating enough
To build bigger muscles you need to be in a calorie surplus, most people are already in a calorie surplus but because they don't exercise the excess calories get stored as fat.
Gym goers tend not to realise that when they become more active the amount of calories they require increases.
This problem occurs mostly when gym goers haven't made clear enough goals. If you want to lower body fat so that you get a visible six-pack then program for that. If you want to gain muscle then you will have to program for that. You can't manage both, so decide what you want.
If you want to gain muscle you must accept that you are going to gain some body fat too, once you have got over that mental hurdle you can begin to increase your calories.
Look for high-protein choices and only make small increases. Check yourself weekly, if you have gained too much body fat then stop raising calories.
Reason #2. You aren't consuming enough protein
Did you know that athletes require twice as much protein as sedentary people?  This is because they need to fuel muscle growth and protein is the macro-nutrient they require to do it.
If you aren't consuming enough protein then your body will be limited in its response to exercise.
Usually, when you train you cause the fibres in your muscles to tear. Then through a process known as Muscle Protein Synthesis the protein you consume in your diet will repair and replace the damaged fibres making the muscles stronger and larger than before.
If you don't consume the extra protein required however, this process will take longer and will be less effective.
Reason #3. You aren't taking the right supplements
If you want to build bigger muscles you are going to want to increase your protein (as mentioned above), one of the most effective ways to do this is to consume whey protein shakes.
Studies have shown that whey protein combined with exercise can improve fat loss compared to exercise without the protein shake .
Another supplement you should be taking is creatine, this supplement can massively improve performance and has cognitive benefits too.
What's more, combining creatine and whey protein is even more effective when it comes to muscle hypertrophy, than whey protein alone 
Reason #4. You aren't lifting enough
If you want to increase the size of your muscles you need to be training regularly, 3-4 times per week should be the minimum.
If you are looking to get bigger cardio should not be required. You will be burning enough calories through weight training to keep fat accumulation to a minimum, and the extra workout time dedicated to weight training will lead to bigger muscles.
Reason #5. You aren't using the right exercises
If you want to get bigger you need to be filling your program with big compound exercises that work multiple muscles. For example the deadlift, where you use more muscles than any other exercise will release more testosterone and growth hormone than the leg press .
Other exercises that you should be including are barbell squats, bench presses, pull ups, push presses, and walking lunges.
Reason #6. Lack of Sleep
If you want to lift big weights you are going to have to sleep more to recover, if it sounds lame having to have a bed time before 12pm then the compensation is massive arms!
Not only will you have higher testosterone and growth hormone levels after a good night's sleep  you will also perform better in the gym following 8 or 9 hours sleep .
Reason #7. Lack of Consistency
Trying out a new program every three weeks? Training four days in a row and then having a ten day break? Eating healthy from Monday morning to Friday lunch and then eating junk throughout the weekend? You are not being consistent.
You need to be following your program week in, week out for three or four months before you can begin to enjoy the results. Hopefully when the results do come they will inspire you to keep going, rather than to rest on your laurels.
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