Increases in lean muscle mass come from consistent weight lifting sessions and providing your body with the fuel and nutrients necessary to heal and grow. A successful muscle building training program will require you to lift weights two to five days per week and complete four to six sets of six to 12 repetitions of each exercise. With this type of consistent training, you will see increases in lean muscle mass.
Your muscles will increase when stimulated by consistent workouts that overload their capabilities. Your muscles will respond to the damage they've incurred by healing back stronger and bigger. To see results, the program you follow will need to be scheduled and designed to adequately overload your muscles and promote muscle building. In addition, as you increase in strength and size, you will need to fluctuate the intensity of your workouts, a concept referred to as progressive overload.
Males will see significantly faster muscle growth results, as they possess a larger amount of testosterone and growth hormone. These are two physiological factors that will allow males to put on lean muscle mass more quickly. Women will see pertinent results, but never to the level of their male counterparts when put under the same training program.
If you're consistent with your workouts and follow a muscle building routine, you should start to see results in about six to eight weeks. More time will be necessary to see more significant changes in your muscle sizes.
Intensity and Frequency
The frequency and intensity with which your train each muscle group will significantly affect your results. If you're interested in gaining muscle as quickly as possible, try incorporating a split routine schedule. This means that you concentrate only on a few muscle groups per training session, which means you'll train an overall more amount of days. For example, a common split routine schedule has you work out your chest, shoulders and triceps on Mondays and Thursdays, then develop your back, legs and biceps on Tuesdays and Fridays. During each session, however, you increase the amount of exercises that each muscle group receives, overloading each one further.
Hypertrophy training is very demanding and at times you may find yourself fatigued. If your level of fatigue will adversely affect your workout intensity, you may consider allowing your muscles a day of rest. Workouts are not effective if they don't adequately overload the muscles. Also, additional rest may be needed to ensure that your muscles have the proper amount of time to heal between sessions.