Anabolism

Our muscles are composed primarily of protein and water, and fat, the main components of our engines. They also store some glycogen, which is fuel in the fuel line, ready to burn. Our engines are largely built during our initial development phases before puberty, with big changes coming during puberty, especially in testosterone-dominant (versus estrogen dominant) persons. These growth spurts give us a big opportunity to change our bodies from those of children to muscle-bound adults. No one wants the body of a twelve-year-old forever!

But how can we harness these mechanisms as adults to build the new physique of our dreams? First, we have to understand the two biggest methods of muscle hypertrophy- myofibrillar and sarcoplasmic hypertrophy. As a fetus and child, we can add muscle fibers to our body, but as an adult, we only add size to our existing fibers.^[2] To add size to our existing fibers, we can increase the number of myosin and actin fibers (contractile proteins)^[3], mitochondria (the powerhouse that converts stored energy into usable energy), water volume, and glycogen stores. The pathways that build the proteins and mitochondria are largely controlled by AMPK^[4] and mTOR^[5], two signals that are activated by anaerobic exercise which depletes our glycogen stores and breaks down our muscle tissues.^[6],^[7] The body’s responses to this breakdown and depletion over time will result in a resilient bounce back of adding more muscle fibers, recycling and creating new mitochondria^[8],^[9], and storing more glycogen (with water) in available spaces in the muscle, instead of just in the liver. This means that exercise, specifically weight training, is very important to break down muscles, and burn off your ATP. This will result in an increase in muscle mass.

Like all mechanisms though, there are multiple ways to stimulate these pathways. Testosterone is a hormone present in humans in varying levels, and has been shown to induce muscle hypertrophy. It binds to androgen receptors in cells, and stimulates muscle building pathways, to include mTOR.^[10],^[11] Exercise can increase testosterone levels for short periods of time^[12], as can maintaining a low level of body fat^[13]. However, many people will use artificial methods to achieve these same effects. Anabolic steroids and Selective Androgen Receptor Modulators (SARMs), mimic these levels of testosterone in the bloodstream. Testosterone, however, is a sex hormone, and affects more than just muscle building, hence why injecting yourself with testosterone leads to side effects such as hair growth, acne, and for females, the development of male sex characteristics^[14]. SARMs, however, are a class of experimental drugs that attempt to bind only to the androgen receptors on muscle tissues, and not in the rest of the body, in order to minimize the side effects^[15]. Additionally, many supplements and “all natural” remedies attempt to increase free testosterone levels in the bloodstream by attaching to hormones that destroy testosterone, or promoting its production. Diet can also play a large factor in testosterone production, as fats are needed to produce hormones^[16] (they are made of lipids). In the opposite manner, alcohol can reduce testosterone, so stay away from drinking if you want to build muscle.^[17] 

In addition to telling your body to build muscle, you must provide it with the right nutrients! Your “mechanic” needs a lunch to sustain him through all this hard work, and he needs the right parts to build these new pieces! A balanced diet of carbs, fats and proteins, will allow your body to be most efficient when exercising and when rebuilding your muscles. Fats (15-20% of calories) are needed for your hormones and brain function, and carbs (55-60%) are needed for your muscles to work, as well as for the muscle building pathways to take the protein (25-30%)^[18] you eat and turn it into muscle.^[19] Of course, you must be in a calorie surplus if you really want to pack on the muscle!

So how do we use this knowledge to help build our muscles? First, you start with a good sleep schedule, getting 7-9 hours of sleep per day to reduce cortisol and keep your testosterone levels high.^[20] Next, get your diet in line, eating as clean as you can, and keeping a proper macronutrient breakdown, for muscle building, as mentioned above. Perform resistance training that will both clean out your glycogen and ATP stores (HIIT or moderate rest period heavy weight lifting), and eat some carbs before and after you work out! Allow your body to rest and recover, hitting each muscle group 3-4 times per week, as you want to spike those testosterone levels as often as possible. Stay away from the alcohol!  Finally, age will lower testosterone levels, particularly in men, so if you’re over 40, ask your doctor if testosterone replacement therapy is for you, and follow lifestyle habits that maximize your hormones; such as avoiding stress, processed food, and environmental toxins Follow these tips and you should be maximizing your body for anabolism and that muscle building!