Without muscle, we would be pretty useless. The muscles of the body enable us to live life as we know it. They let us lift, carry, push, pull, walk, run, scratch, and hug. They can get stronger, weaker, bigger, smaller, tear, heal, tighten, and stretch. These movements and features are complex, and muscles are incredibly advanced to make it all happen.
Extra Science Alert: This one is a bit of a sciency post. I’ve done my best to make it as easy to read as I can. Even if you hate science, try to read through anyway. Understanding how the muscles work, just like learning how fat works, is super important. We have to know what something is in order to know how to use it to our advantage. Understand how to grow and maintain those beautiful muscles of yours is key to making your body work for you.
Different Types of Muscles
Not every muscle in the body is the same, and you have muscle in places you might not think of. There are 3 main types of muscles throughout the body: Smooth, Cardiac, and Skeletal. Skeletal muscle is what we usually think of first, the muscles that connect to your bones and drive your movement. These are primary muscles used during exercise, and are attached through connective tissue called tendons.
Smooth muscle is a little deeper, and it actually makes up the lining of many of the internal organs. These help our organs and internal systems function, and generally cannot be contracted voluntarily. Cardiac muscle is last. As it’s name implies, it’s what the heart is made of, and also cannot be directly controlled. Even though we can’t intentionally contract it, but like skeletal muscle, the muscles of the heart can be strengthened through exercise and training.
How Do Muscles Work?
Here’s the relatively simple version: Skeletal muscle is made up of chains of proteins called myofibrils. These overlap, and work to move the muscle. They pull together to contract and shorten the length of the chains, and they can relax to expand and lengthen. All of this needs energy to happen, and that energy comes from the breakdown of ATP molecules.
Those myofibril chains then come together to create full muscle fibers, or myocytes. These fibers also contain glycogen, a carbohydrate which helps provide more energy for exercise, and myoglobin which stores oxygen. Muscle fibers are surrounded and bundled together repeatedly by fascia, forming the complete muscle as we know it.
All of these muscle fibers work and move together across the entire muscle. Muscle action does not use every muscle fiber, since each fiber can be switched on or off independently. Depending on how much strength is needed in a particular situation, more or fewer groups of muscle fibers contract.
Muscles can contract in a few different ways. There’s the standard Concentric Contraction which leads to movement working against the direction of gravity. Next up is Eccentric Contraction which leads to movement working in the same direction of gravity as a sort of braking mechanism. Finally, there is Isometric Contraction, which engages the muscle but keeps it holding in one place without any movement.
Muscle Fiber Types
Even though they all do the same two movements, contract and relax, muscle fibers are not all equal. They come in two main forms, Type I and Type II, also known as slow twitch and fast twitch. Each muscle usually is made up of a combination of both fiber types. The proportions are different depending on the muscle group, and vary from person to person. The composition of Type I and Type II fibers can also change depending on your training and exercise.
Type I muscle fibers are called Slow Twitch because their myofibrils contract more slowly. They are aerobic, which means that they use oxygen for when they transfer energy. This helps them work at lower intensities and for a longer time. Because of this, they are great for bigger things like keeping up posture and stability.
Type II muscle fibers are known as Fast Twitch because of their short bursts of strength and speed. Because they can act quickly, they can’t use this power for long periods of time, and end up fatiguing sooner. They also access ATP faster, utilizing quick bursts of energy. Because of this, Type II fibers are not always activated, unless the muscle is putting out a large level of force. As a result, Type II fibers are responsible for a big chunk of the body’s movement, and play a big part in muscle size and definition.
How Do Muscles Change Size?
Because of all of this, muscles have the awesome ability to adapt and change in size over time. They can grow or shrink depending on the level of muscle activity. Exercise can spark more myofibril protein chains to be created, which increases the size of the muscle fibers. Because muscle fibers are mainly made of protein molecules, they need more protein to grow. If you don’t eat enough protein, your muscles won’t grow, and can even shrink through atrophy. While this can also happen as a result of injury or disease, the most common cause is inactivity. If muscles aren’t put through enough consistent activity and stress through exercise, they can waste away. This is generally not permanent, and rebuilding usually takes less time than it did to build up the first time.
Exercise is a complicated process using the entire body, with muscle as a key player. Knowing about the composition and function of the body’s muscles is key to understanding how to use them to your advantage. Now that all the science is out of the way, you can moving forward to start using those muscles to increase strength and overall fitness.
Figuring out the most effect exercise program for the goal of losing body fat can be challenging. The first step is knowing why the body makes fat, understanding how the body gets rid of fat, and that you can’t target specific areas to lose fat. After that, it’s time to make a plan and get started moving. In terms of the best way to get rid of that fat, there is a ton of conflicting information on which is the best route for fat loss: Cardio or Strength Training. Each style has its own benefits and drawbacks in the quest for getting rid of fat.
Gym noises are frustrating and I hate them. They’re distracting, annoying, and make people hate going to the gym. I hate the yelling, the grunting, the moaning, and the steam engine blowing breath. But I hate slamming and dropping weights the most. But it’s just not because of the noise. Putting down your weight is just as important as picking it up.
For better or worse, our bodies are really efficient at storing energy for later. This is super helpful when we’re starving and need to find food to eat. It’s super unhelpful when we build up a big chunk of stubborn body fat from all this excess energy. Unfortunately, getting rid of this extra energy and fat isn’t as easy as just doing crunches to get rid of the belly. The body has its own process of using up and removing fat, and sometimes it’s not exactly what we want.
So you finally built up some well-deserved confidence, made it to the gym, tried some new things, logged in a hardcore workout, and went home feeling super accomplished and swole. And then you wake up the next day and you can’t move.
What is Soreness?
That soreness and tightness you feel long after a tough workout is known as Delayed Onset Muscle Soreness, or DOMS. This is a bit different from the soreness you may feel during and right after a workout, known Acute Muscle Soreness, which goes away within a few minutes or hours.
DOMS usually kicks in 24 to 48 hours after a new exercise session. This is why you may feel even more sore two days after a particularly grueling workout, or the first time back into it after a long break. Have no fear, It usually goes away within a week.
Is Fat Bad?
Most of us have some fat we’re trying to get rid of, and it can affect the way we see and feel about ourselves. But it’s important to remember that we as humans need fat in order to live. Developed as survival mechanism, body fat helps us when food and energy are not immediately available. Body fat is an easy way to store energy when we have a surplus, and allows us to tap into it when there’s scarcity. The trouble comes with excess fat.