It is not a rare thing in the fitness world to want to be bigger, stronger, or more defined. For that reason, among the most common goals in fitness is muscular hypertrophy (muscle growth).
But having adequate lean mass is much more than just being strong and looking a certain way.
As we spoke about in the last article, an increase in muscle mass produces an increase in resting metabolic rate (which contributes to roughly 60% of your total daily energy expenditure).
The more muscle mass you have, the more energy your body requires to maintain itself, meaning you get to eat more without gaining weight.
So no matter what your goal is, whether to be stronger, look leaner, or just lose weight and keep it off, adding lean mass is extremely important.
What is muscular hypertrophy?
Muscular hypertrophy (hereby referred to as just hypertrophy) is the increase of the cross-sectional area of muscle tissue (i.e, muscle growth) occuring when protein synthesis exceeds protein breakdown.
There are two types of hypertrophy; myofibrillar and sarcoplasmic. It is not necessary for you to know too much about these so I’m just going to give you a very brief overview.
Myofibrillar hypertrophy is the enlargement of contractile elements (myofibrils, actin & myosin). Actin and myosin are the two proteins that pull on one another during the sliding filament theory, causing the muscle to shorten/contract. As these myofibrils increase in size, so does the entire muscle.
Sarcoplasmic hypertrophy on the other hand, is the increase in non-contractile elements and fluid (glycogen, water, mitochondria, etc). This type of hypertrophy is believed to be training specific due to the fact that some studies show hypertrophy being different between bodybuilders and powerlifters. (1) Usually, though strong, bodybuilders are much larger but with less strength compared to powerlifters.
So, sarcoplasmic hypertrophy can be described as the increase in the space within the muscle fiber as opposed to the increase in the myofibrils within the muscle fiber (myofibrillar hypertrophy). Both of these are believed to happen simultaneously, however, one happening at a higher rate (or to a greater extent). For example, when myofibrillar hypertrophy occurs, there is an increase in the sarcoplasm, however it is to a lesser extent.
For more on this see this article here, https://www.strongerbyscience.com/sarcoplasmic-vs-myofibrillar-hypertrophy/
How does muscular hypertrophy happen?
As mentioned before, in order for muscle to grow, protein synthesis must exceed protein breakdown (i.e, the proteins within a muscle must be built up more than they are broken down).
It is commonly thought and/or believed that hypertrophy occurs through muscle damage alone. Though muscle damage is a contributor to hypertrophy, it is but one of the three.
The other two contributors or causes of muscular hypertrophy are mechanical tension and metabolic stress.
You can easily remember these by referring to them as The 3 M’s of muscular hypertrophy; Muscle Damage, Mechanical Tension, Metabolic Stress
A brief overview of these 3 mechanisms
This is the small (or large) tears that occur within a specific area of a muscle caused by unaccustomed work performed by that muscle. Eccentric exercise (lengthening of a muscle/the lowering phase) is known to be more damaging than concentric (shortening of a muscle/positive phase) and isometric exercises (muscle contracts but does not shorten or lengthen because the load exceeds the muscles capability).
“It is believed that tension associated with resistance training disturbs the integrity of skeletal muscle” (1). When you perform a resistance exercise, you are producing mechanical tension through the force you generate as well as the stretch of your muscles during that exercise. Though mechanical tension alone can cause hypertrophy it is not likely to be the sole cause.
“Metabolic stress manifests as a result of exercise that relies on anaerobic glycolysis for ATP production, which results in the subsequent buildup of metabolites such as lactate, hydrogen ion, inorganic phosphate, creatine, and others”. In other words, metabolic stress occurs from the buildup of metabolites (a byproduct of metabolism) produced by the specific type of energy production. According to Dr. Andy Galpin, the role that metabolic stress plays in muscular hypertrophy (in healthy individuals) is still fairly unclear. Whereas, muscle damage and mechanical tension are more proven, accepted, and understood. (3)
2 Key Points for Achieving Hypertrophy
– Train with varied repetitions.
Though it is commonly recommended to train in the 8-12 repetition range when training for hypertrophy, training rep ranges should vary (and can vary from as low as 3 reps and as high as 30 reps). There are several ways you can add this type of variation in your training.
1. Through small training blocks (4-6 weeks) of each rep range (4 Weeks- High, 4 Weeks- Moderate, 4 Weeks- Low)
2. Varying the rep range per week (Monday- Low, Wednesday- Moderate, Friday- High)
3. Varying the rep range within workout (1-2 sets- Low, 1-2 sets- Moderate, 1-2 sets- High)
I prefer the first 2 options, though I usually stick with option 2 (varying rep ranges throughout the week).
– Slowly increase calories and be patient.
Just as you need to be in a caloric deficit to lose weight, you must be in a caloric surplus to gain weight. Also, as with weight loss, the slower you go the better. Aim to gain about 1 lb a week by eating 250-500 calories above your Total Daily Energy Expenditure (though the rate in which lean mass is and can be gained will vary greatly per individual, possibly anywhere from 0.5 lbs a week to 2 lbs).
Overall, focus on progressive resistance training (continuing to safely progress in whatever fashion of resistance training you prefer/continuing to add resistance), eating quality, nutrient-dense food, above maintenance calories (eating 250-500 calories above what your body needs to maintain body weight), and getting sufficient rest (several off days within a week, 48-72 hours between workouts, and taking a break (deload) every 4-6 weeks).
How does hypertrophy benefit your weight loss goals?
Many who want to lose weight and keep it off, mistakenly negate muscle growth and do their best to lose weight (at any cost, e.g, losing as much muscle as they do fat). This is a recipe for disaster, however, and the mindset of those losing weight must be changed.
An increase in muscle mass is beneficial not only in giving you a leaner look but it directly affects your total daily energy expenditure.
By increasing muscle mass you increase your resting metabolic rate, which accounts for roughly 60% of the calories your body uses everyday. The higher your RMR, the more calories you can eat daily without gaining weight.
The less you weigh the less energy your body needs. So, if an individual continues to lose weight (without gaining muscle mass) they are going to have to continue to eat less and less. Whereas, an individual who, say, loses 5-10 lbs (of fat) and then proceeds to gain even 2-5 lbs of lean mass (over the following year or so after weight loss) will be able to eat just as or nearly as much as before they lost weight (speculatively, there are many variables in this, I am just giving a general idea). Muscle is more metabolically active than fat, therefore requiring more energy.
An emphasis must be put on gaining, or at the very least maintaining muscle mass if the goal is fat loss. Weight must stop being such a huge factor (to some degree) and body composition becoming the higher focus/priority.
Muscular hypertrophy occurs when protein synthesis exceeds protein breakdown.
Hypertrophy is caused by 3 key contributors, which you can remember as the 3 M’s of hypertrophy; Muscle damage, Mechanical tension, and Metabolic stress.
Gaining muscle mass is usually not seen as a weight loss maintenance strategy, however, through increasing your muscle mass, you can increase your resting metabolic rate which allows you to eat more while maintaining your weight.
It’s not about losing weight, it’s about improving our body composition. Being leaner, stronger, and healthier.
So, whether your goal is to be stronger, more lean, or just maintain weight loss, muscular hypertrophy can be extremely beneficial.
Hope this article was helpful, best of luck to you in all your fitness endeavors!
Michael Cruz, COFC
References & Sources