Anyone looking to add lean muscle knows it never develops as quickly as you want, and nothing is more frustrating than hitting the gym for weeks without results.
But experts agree that a few easy changes to your training and diet, might be all you need to increase lean muscle fast.
These 5 tips can be applied in any order, and are some of the fastest and easiest steps you can take to increase lean muscle mass and completely transform your physique.
1. Compound Exercises
These should be the bread and butter of your exercise routines. Heavy compound lifts such as deadlifts, squats, and bench press involve multiple muscle groups and stimulate a greater growth hormone release. 
Cables and other machine exercises still build muscle, but for adding size quickly, nothing works better than compound movements with proper form.
2. Muscle Confusion
You must shock and overload your muscles into growth. If you arenâ€™t naturally strong, donâ€™t worry. Take 1-2 weeks and perform all exercises in a low rep range. This is often referred as periodized training  and is used to build strength and mass at the same time.
The optimal range for muscle hypertrophy is generally considered 6-12 reps.  However, taking a week or two to focus on 1-4 rep range strengthens type 2 muscle fibers, which in turn increases force production and strength.
Also, incorporating drop and super sets into your workout routine increases your intensity, forcing your body to work harder and to grow.
3. Know Your Nutrition
Weâ€™ve all seen people who have the same physique year after year, and never seem to make any progress. Ask about their diet, and youâ€™ll discover they arenâ€™t concerned about calories and donâ€™t give even a second thought to what they eat before or after a workout.
If you want to build muscle quickly, the importance of proper nutrition cannot be overstated. Eating 6 meals a day with lean protein sources such as chicken and turkey provide the building blocks to repair and rebuild damaged muscle.
Slow-digesting carbohydrates such as sweet potatoes, oatmeal and brown rice fill muscles with glycogen, giving you the energy you need to exercise. However, you also need to be aware of how your body responds to carbohydrates. Too many carbs may expand your waistline quicker than your muscle.
For building mass, nutritionist Chris Aceto recommends 2 grams of carbohydrates per pound of bodyweight.  If youâ€™re gaining more fat than muscle after a couple weeks, youâ€™ll know you need to back off the carbs.
Another way to build muscle quickly is by getting adequate rest and recovery. Bodybuilder Lee Haney is famous for saying, â€œstimulate donâ€™t annihilate.â€  When it comes to building muscle, less is often more. You donâ€™t need to have 2 hour lifting marathons at the gym every day to grow.
In fact, working out is only half the equationâ”€ it catabolically tears muscle down and raises cortisol levels. Muscle is built through rest, sleep and healthy nutrition. In fact, sleep is one of the most anabolic states for the body, and is when you release the majority of your growth hormone. 
Sleep deficiency impairs blood sugar regulation and can halt or cause major setback to muscle growth. 
While not a substitute for proper nutrition or training, supplements can speed recovery and boost strength as they help you build lean muscle mass faster and easier than on your own. From pre-workout supplements, to protein and creatine and even multivitamins, supplements can make a significant difference in the rate you increase lean muscle mass.
A pre-workout supplement can also do wonders for building muscle quickly. Utilizing a mixture of caffeine, creatine and a nitric oxide booster such as arginine, pre-workout supplements increase strength, improve muscle pump and delay fatigue.
Follow your workouts with a protein supplement and/or creatine to fuel the muscle building process and speed recovery time. The amino acids you feed your body will translate into a significant increase in protein synthesis to help you see results much faster.
Exercise rapidly depletes essential minerals and electrolytes, and actually causes oxidative damage to the body with free radicals. A multivitamin contains antioxidants, vitamins and minerals to replenish micronutrients and keep cells healthy.
Time in the Game – Consistently Eat Right and Exercise Regularly
Ultimately, building muscle equates to time in the game, meaning time spent eating and training correctly. Muscle gains always come sooner and easier to those in their first few years of lifting. After that, it takes much more to coax the body into growth.
No matter where you start, as long as you are consistent and follow the tips outlined above, you will be increasing lean muscle mass before you know it.
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