Building lean mass often times takes more than just lifting heavy weight, it requires specific planning that takes into account multiple factors. That of course if you want to see results effectively. Whether the goal is to merely become stronger or become leaner for aesthetic purposes, the training approach, as well as the physiological processes, remain the same. Usually, hypertrophy comes as a result of increased strength. Even though it has been proven that in certain cases there can be strength gains without increasing muscle size, they usually come hand in hand. It is important to keep in mind, though, that at the beginning of any training program strength is gained just by improved neural adaptations rather than muscle size. Thus, strength and muscle mass only start having a positive correlation after the first couple months of training. In order to cause hypertrophy the following three factors must happen: mechanical tension, muscle damage, and metabolic stress.
Mechanical tension refers to force produced by a muscle, which ideally should damage the structures in the muscle. To generate an increase in muscle cross-sectional area, the muscle needs to be overloaded so that the nature of the myofibers can be altered (muscle damage).Metabolic stress addresses how much the muscle is “pushed” to its limit and how by doing so, certain hypertrophic responses are stimulated. It is here when training methods come into play. Load, sets, reps, and rest intervals are the variables that constitute a training program, and so each variable must be manipulated in a very specific way in order to increase the chances for hypertrophy.
So let’s just go straight to the point and talk exactly how these variables need to be manipulated in order to make the muscle grow. In terms of repetitions, most research suggests to keep a moderate level of reps (6-12), which will depend on the type of movement you are doing. Usually the main lifts, the ones that are more taxing on your nervous system, should go first and should have less reps than movements that isolate muscle groups ( e.g deadlift vs hamstring curl). For the main lifts, reps are 3-6 and for sets it is recommended to do 3-5. For assistance exercises you want to definitely go for more than 8 reps, keeping the same range of sets. Just to clarify and leave no room for doubt, assistance exercises are those that isolate muscle groups and focus on specific and small parts of a certain movement or body part.
When it comes to intensity, the muscles should be subjected to loads that are heavy enough to cause muscular damage. It is recommended to work with loads that are 70% and above the 1 repetition-maximum (1RM) or the heaviest weight a person could lift for one rep.
The last variable is rest interval. Resting plays an important role because muscle growth comes as a result of a proper balance between metabolic build-up and restoration of full force. Since the training intensity is going to be high, and the person is going to be exerting almost maximal force, there is going to be metabolic build-up as a consequence of fiber damage and by products of glycolytic processes. Such build-up consists of lactic acid, interstitial fluids, hydrogen, etc. And so, moderate rest interval is recommended so that there can be full restoration of force, but not complete clearance of the build-up. The accumulation of fluids and metabolite is actually beneficial for muscle growth. A moderate rest interval would be anything between 30-90 seconds.
So there it is, the exact recipe for hypertrophy or increased muscle size. If you follow these recommendations and play with the different variables correctly, you should start seeing results in a matter of months. It is important to keep in mind too, that nutrition as always plays an essential role. The building blocks of muscle are amino acids, which is protein so it is important to have a correct intake of quality protein so that our bodies can use that to build muscle.
Hope you enjoyed reading this, and most importantly, hope you learned something new!