There are few things in life more frustrating than waiting for the visual results of exercise to appear. Whether we verbalize it or not, we have all thought it before: “I know exercise works, but how much longer do I have to do this before I SEE a difference? It’s enough to make you want to abandon the gym altogether and go on a crash diet. However, as is the case with so much else in life, changes must take place on the inside of your body before any kind of changes on the outside can appear. That’s where understanding a little bit about what goes on in your body when you embark on a workout program becomes little helpful.
By its nature, the body has built-in response capabilities that allows it to overcome and adapt to the millions of stressors of its external environment. When you breathe in dust, your body coughs it out in order to keep it out of the lungs. When you get cut, your body develops a scab in order to keep dirt from getting into your blood stream and causing infection. Likewise, resistance training is also a stress (albeit deliberate) that is placed on the body that requires a number of adaptations to occur in order to overcome them. Namely, these adaptations effect the body at the neurological, muscular, endocrine, and anthropomorphic levels.
Neurological changes are the first to occur when working out. Because our muscles are controlled by the firing of neurons, over time the body must learn to increase both the intensity and the frequency of these firings in order to allow the muscles to repeatedly work over a given number of repetitions or at a given amount of load. The increase in frequency of the neuron firing a muscle fiber is known as “rate coding,” and is responsible for developing efficient coordinated movement in your muscles over time. Additionally, the body’s ability to lift heavier loads with training is due to “increased motor unit recruitment,” which occurs when the amount of muscle fibers that a given neuron innervates is increased-the more muscle fibers that fire at one time, the more weight you can lift!
The next adaptation the body goes through occurs within the muscle belly itself. Within each muscle group in our body, we have two basic types of fibers that are responsible for completing different activities. Type I muscle fibers are responsible for activities that require long duration and low loads like running, walking, and maintaining our erect posture. Type II fibers are the ones responsible for quick bursts of energy, under heavy loads, for short duration like weightlifting and jumping. Specifically in regards to the type II fibers, chronic and progressive resistance training causes these fibers to grow in size, known as “hypertrophy,” which allows the body to lift heavier weight.
Third, the endocrine, or hormonal, system must undergo some changes, typically occurring a few months after you have stayed consistent with your training program. Although there are a plethora of different hormones that have a role in the body’s development from resistance training, growth hormone and testosterone are the two most important when it comes to muscle repair, development, and maintenance. After each workout that you complete, testosterone and growth hormone are released in order to take protein and repair the muscle fibers that were damaged from the weight that you lifted. As a result, over time and repetitive bouts of resistance exercise, these hormones build your muscles stronger, leaner, and denser so that they can withstand more and more weight as you go through each workout of your program.
Lastly, the anthropomorphic, or body-shape, changes occur. This is where the fun begins! As a result of all the internal changes that occur over months of regular resistance exercise, the body finally starts to take the desirable shape and appearance that you want. Namely, due to the increased percentage of your body weight now being comprised of muscle, your body uses any stored fat you may have in addition to the calories you consume from food, and devotes them entirely to maintaining your muscles. Your muscles literally turn your body into a fat-burning machine! Furthermore, since you have less fat underneath your skin, your muscle definition begins to appear more prominent, giving you an overall tighter, firmer, and slimmer figure. FINALLY!!
Lift after lift, workout after workout, you put all your effort in and see little immediate results in the end. It seems like it takes forever for all these adaptations to occur! Until that day when you catch yourself in the mirror and you see an ab muscle. Or, you get praised about how good you look by a friend or family member who might not have seen you in a while. And finally you realize your patience and hard work WAS ALL WORTH IT.
Joe Gernetzke CSCS