Good fitness. What it is.

Often, we consider somebody fit and healthy based on how they look. If a person demonstrates a developed musculature and a low body fat percentage then he or she is very fit. Well, it might be the case. However, as we say in Russia, “don’t judge a book by its cover.” Here is what good fitness should be all about.

Strength

When we say he or she is strong what does it really mean? Let's have a look.

Any object on Earth has a mass and a weight. These two slightly differ from each other. Mass refers to the amount of matter an object contains whereas weight is a force exerted on the object by gravity and is calculated based on the object’s mass. You must have heard of famous Newton’s second law, F=mg. We can use it to calculate the weight.

For example, If a person, standing on a bathroom scale, sees the number 70kg on it, then it is their mass and not weight. The weight would be equal to the person’s mass multiplied by g, where g is the acceleration due to gravity; this number is a constant (in a vacuum) - 9.8m/s2. Thereby the person would weigh 686N (a weight is measured in Newtons and not kilograms).

Since an object on Earth would always have weight, which is a force, the only way for us to lift it is to produce a greater force by flexing the muscles. Hence, physical strength is the ability to produce the force required to overcome an object’s weight. Another question is what “being strong” means.

Depending on a social environment, it might refer to different qualities, such as lifting more than an average person, the ability to win a fight or run faster, and etc. All of these can be deemed as “being strong.” In other words, it is subjective. I propose the following definitions: one is strong if their muscles can generate enough force to perform desirable actions. It can be anything from running and walking to lifting a heavy barbell. If the muscles can provide enough force to accommodate whatever we want to do, then we are strong. If fewer efforts allow us to perform the same action, then we have become stronger.

As you can see, being strong is relative and depends on specific parameters, often within a particular scope. For this reason, we need to be careful when comparing our strength to the strength of other people, because we might end up matching an apple to an orange. Instead, I encourage you to have a personal goal of becoming one percent better than you were yesterday every day.

Stamina of strength

When the muscles can create enough force to lift something, whether it is an object or our bodyweight, the question is for how long they can do it uninterruptedly. A simple example is a static hold. Say a person can do one pull-up. It means the muscles can generate a force that exceeds the one exerted on the body by gravity. In this case, the person is strong enough to perform a pull-up. The stamina of strength will be characterized by duration he or she can stay at the highest point, preferably touching the bar with the chest.

The stamina of strength is the ability of a muscle to produce a maximum effort without a break for some time. The longer, the better. This ability is important for physical development as it helps to prevent injuries and allows increasing the complexity of exercises.

For instance, when you lift something substantial, the muscles might give up in the middle of the action leading to a sprain. Or shall you decide to take the handstand further by performing the handstand walk, then the good stamina of the shoulders’ strength would be a must.

Power

Often there is a confusion between strength and power. We already know that strength is the ability to generate sufficient force. However, this concept does not take into account how fast the force is produced. If we combine force and time together, we get power.

Power is the ability of the muscles to generate sufficient force within a short period. The shorter the better. It is also known as explosive strength. For instance, a single repetition of the 100kg dead-lifts might last two to five seconds, whereas a single repetition Olympic jerk (clean and jerk) with the same weight must be accomplished within a second. The former is an example of strength; the latter is an example of power.

It is worth noticing that power does not always imply lifting heavy. A jump, kick, or run can be powerful if performed fast. The sport takes advantage of power. In Gymnastics, many elements require to move the body into a certain position more quickly to minimize the gravity pull; otherwise, it might be impossible to accomplish.

Stamina

Stamina is the ability of the muscles to produce movement or generate static contraction for as long as possible. Different muscles might have different stamina. One might be able to run for long, yet not be able to hold a plank for a minute. Therefore the muscles need to be subjected to individual stamina training. In my next post, I will explain how stamina works in the body in more detail.

Flexibility

This aspect of fitness has a tremendous impact on the overall state of well-being. However, the essence of muscle flexibility is often vague and confused with mobility. Let's make it clear.

The muscles are matter, comprised of organic chemical compounds. Any matter has several physical qualities, including flexibility, which is an ability to be elongated. The more it can be elongated with no damage to its structure, the more flexibility it has. Whereas it is intuitive to extrapolate this concept onto the muscle flexibility, it would not be correct. Think of a muscle as a resistance band with a toughness level of seven, guaranteed by its manufacturer. It means that it can be elongated only by twenty centimeters (a random number) before it stops. Regardless of how often and for how long we stretch the band - its limit will stubbornly remain constant - twenty centimes.

The same is right about the muscles. From birth, the muscle tissue as the biological substance has only that much flexibility, and It will stay unchanged regardless of one’s stretching routine and exercises. A reasonable question arises - how a person, unable to bend over to touch the floor, in a couple of months of training becomes able? Again, in my next post I will tell more about the physiological mechanism of flexibility, but for now, please accept this brief explanation.

Everything in the body is controlled by the Central Nervous System (the CNS), including the muscles. At some point in life, out of precaution, the CNS starts limiting the muscles’ ability to lengthen and does so at a varying degree in each muscle. Albeit the absolute limit of elongation is constrained by the physical quality of the muscle tissue, the CNS creates a relative limit within the absolute limit of each muscle. Once the relative limit has been established, the CNS will reflexively tighten a muscle every time its length approaches its relative limit. This defense mechanism has a pure intention to prevent us from injuries. Ironically, often it does the exact opposite.

Therefore, flexibility is an extent to which a muscle can be safely stretched with little or no resistance. The flexibility is very important as it allows a joint to move at a broader range, contributing to its mobility, which we will discuss next.

Mobility

Mobility comes especially handy when we set to perform a complex activity, for example, dancing or swimming. Whereas flexibility concerns the muscles, mobility deals with the joints.

The body produces any moments by contracting the muscles, the muscles pull the bones, the bones move - we move. When a couple of bones come together, they form a joint. The shoulder joint, the hip joint, the elbow joint are all familiar to us. The joints are held together by the muscles, connective tissue, and ligaments. The latter are very sturdy elastic tissue, structurally more sound than the muscles, and connect bones to bones. The muscles and ligaments work together to provide the body with more freedom of movements - mobility.

Mobility describes the range we can comfortably move the body parts through, and we want to keep this range as wide as possible. However, In some cases, we would need to keep it narrower for injury prevention reasons. We will talk about it later. Important to notice, that to improve mobility we need to enhance muscle flexibility first, so that the muscles can be stretched with no resistance to allow a joint to move freely.

We must treat mobility training with caution as to not damage the ligaments. If a joint is brought to its extreme range, then its structural integrity is guarded mostly by its ligaments and not the muscles. For this reason, we need to allow the ligaments sometimes to adapt to a new range after muscle flexibility has been improved.

Coordination

Coordination is the brain’s ability to control the body parts and be aware of their positions in space. Another definition of coordination is body awareness. For example, when we dance, we want to know where our body parts are and what they do. It allows us to move as we planned or adjust the body’s locomotion on the go.

Balance

Balance is the ability to keep the body or some of its parts motionless in a chosen position. Let’s say a person performs an unsupported handstand, where the main goal is to keep the body still and use only the fingers and shoulders to achieve balance. At the same time, we need to keep the shoulders, the torso, and the legs aligned, which can be problematic without seeing them. Therefore balance is based on coordination/body awareness.

Another situation is when we need to move the body parts to achieve balance. The slackline is a great example. If we do not have prior experience, it will be difficult, because balance, like muscle flexibility, is hardly universal. An unfamiliar element based on balancing would most certainly require even a professional gymnast some extra training to accomplish it by tuning their CNS to the new task.

That is it. If we take care of these components, then an excellent physical shape and good look will be a nice bonus. In my next post, we will have a closer look at the simplified physiology of these processes.