1. Up Your Training Volume

Ava Fitzgerald, C.S.C.S., C.P.T., a sports performance coach of the Professional Athletic Performance Center in New York says “Compared to training for strength, intensity is going to drop during the hypertrophy phase of a program, with intensity sitting between 50 and 75 percent of the person’s 1RM, the maximum weight he or she can lift for one rep,”

To get the volume your muscles need, she recommends performing each of your lifts for three to six sets of 10 to 20 reps.

2. Slow down on the Eccentric Phase

According to research published in the European Journal of Applied Physiology, eccentric work is far better at triggering hypertrophy. The eccentric phase of your lift is the movement when you muscle is lengthening, also known as the negative phase.

To increase the amount of eccentric effort in your workout, you can do two things: either slow down the eccentric phase of each exercise you perform or integrate eccentric-only variations into your routine.

3. Reduce your Rest Between-Sets

According to the Journal of Applied Physiology, irrespective of rep and set scheme, fatiguing your muscles is a prerequisite for hypertrophy. Rest periods of 30 to 90 seconds encourage a quick release in muscle-building hormones (including testosterone and human growth hormone) while also making sure that you really, truly fatigue your muscles, according to the research.

4.  Eat More Protein

Since exercise breakdown your muscle and protein rebuilds your muscle, it only makes sense to increase your protein intake if you are training hard and trying to build more muscle.

Research from the University of Stirling suggests that weight lifters need to eat 0.25 to 0.30 grams of protein per kilogram body weight per meal for muscle growth.

5. Focus on More Calories

Now it is impossible to build muscle if you are burning more calories than you are consuming every day, but the type of calories are also very important. In a 2014 Pennington Biomedical Research Center study, people who ate a high-calorie diet rich in protein stored about 45 percent of those calories as muscle, while those following a low-protein diet with the same number of calories stored 95 percent of those calories as fat.

6. Drink Casein Protein Before Bed

Because casein protein absorbs slowly into the bloodstream, it is able to feed your muscle a constant supply of protein and amino acids while you are sleeping and recovering. In one Medicine and Science in Sports and Exercise study, consuming casein protein immediately before bed boosted young men’s levels of circulating amino acids for 7.5 hours; they built muscle all night long while they slept.

7. Get More Sleep

According to a study in the Journal of the American Medical Association, sleeping for five hours, as opposed to eight hours, per night for just one week cuts muscle-building testosterone levels by a whopping 10 to 15 percent.

The National Sleep Foundation recommends that adults ages 18 to 64 sleep seven to nine hours per night. No excuses.

8. Supplement with Creatine

Creatine doesn’t directly grow muscle. But by boosting your performances at high-intensity lifting workouts, the natural compound effectively promotes muscle growth, according to the  Journal of the International Society of Sports Nutrition.