What is fitness and who is fit?
Since the concept of fitness is not easy to define,
there are a lot of different definitions, even
though some of them are very similar to each
Here are some examples:
• Merriam Webster’s Collegiate Dictionary defines
"fitness" and being "fit" as “the ability to transmit
genes and being healthy ”( fig.1);
• Microsoft Encarta Reference Library sais that
“Physical Fitness is
the ability of the human body to function with
vigor and alertness, without undue fatigue, and Fig.1
with ample energy to engage in leisure activities,
and to meet physical stresses”;
• Physical fitness is defined as "a set of attributes that people have or achieve
that relates to the ability to perform physical activity" (United States
Department of Health and Human Services, 1996).
• Fitness means being able to perform physical activity. It also means having
the energy and strength to feel as good as possible.
• Fitness generally refers to the idea of your body being in good shape. It
can mean a number of different things: eating a healthy diet (fig.2),
exercising (fig.3), not being overweight, taking care of yourself, getting
enough sleep, and otherwise being in good condition.
So, we can see that fitness is not about being thin, having a small waist or
having bulging muscles. It is a combination of qualities that enable us to
be at our full potential in performing vigorous physical activities.
Physical Fitness involves the performance of the heart, lungs, and the
muscles of the body. Specifically, and according to some experts, it takes
into account our Cardio Respiratory Endurance, Muscular Strength,
Muscular Endurance, Body Composition and Flexibility.
To some extent, Fitness also influences our mental and emotional
development, since what we do with our bodies also affects what we can
do with our minds.
So, let’s look to all of these five components separately and understand
what they are and how we can improve them:
Cardio Respiratory Endurance
It is the ability of the body’s circulatory and respiratory systems to supply
fuel during sustained physical activity. To improve your cardio respiratory
endurance, try activities that keep your heart rate elevated at a safe level
for a sustained length of time such as walking, swimming (fig.4), or
bicycling. The activity you choose does not have to be strenuous to
improve your cardio respiratory endurance. Start slowly with an activity
you enjoy, and gradually work up to a more intense pace.
Muscular strength is the ability of
the muscle to exert force during an
activity. The key to making your
muscles stronger is working them
against resistance, whether that is
from weights or gravity.
If you want to gain muscle strength (fig.5), try exercises
such as lifting weights or quickly climbing the stairs.
Muscular endurance is the ability of the muscle to continue to perform
without fatigue. To improve your muscle endurance, try cardio respiratory
activities such as walking, jogging, bicycling, or dancing (fig.6).
Body composition refers to the relative amount of muscle, fat, bone, and
other vital parts of the body (fig.7). A person's total body weight (what you
see on the bathroom scale) may not change over time. But the bathroom
scale does not assess how much of that body weight is fat and how much
is lean mass (muscle, bone, tendons, and ligaments). Body composition is
important to consider for health and managing your weight.
Flexibility is the range of motion
around a joint. Good flexibility in the
joints can help prevent injuries
through all stages of life. If you want
to improve your flexibility, try
activities that lengthen the muscles
such as swimming or a basic
stretching program (fig.8).
What’s your definition of fitness?
When we made a small inquiry and asked people what they thought
fitness was, we heard several ideas, some of them completely different
from each other. Since being some sort of activity in which we play cards
or watch television, to having a body without cellulite…
Generally, young people say that it is a dynamic sport which is mostly
practiced by women and helps them to lose weight. Other teens say that
is a sport or activity which improves our ability to perform physical activity
and, together with a healthy diet, makes us feel and look better and live a
healthier life. A boy also answered that fitness consists of keeping yourself
in a good physical shape.
Older people, usually older than 40 years old, didn’t have, in general, a
clear idea about the definition of fitness and some of them answered that
they didn’t know what is was. However, some people guessed that it was
probably a sport, a physical game or a hobby. Others even added that a
healthy diet was also important and sport or physical activity wasn’t the
only thing that mattered when we talk about fitness.
Any type of exercise uses your muscles.
In running and swimming, your muscles are
working to accelerate your body and keep
it moving. In weightlifting, your muscles
are working to move a weight.
Exercise means muscle activity!
In strenuous exercise, just about every
system in your body either focuses its
efforts on helping the muscles do their
work or it shuts down.
For example, your heart beats faster during
strenuous exercise so that it can pump
more blood to the muscles, and your
stomach shuts down during strenuous
exercise so that it does not waste energy
that the muscles can use.
When you exercise, your muscles act like
An electric motor uses electricity to supply
its energy. Your muscles are biochemical
motors, and they use a chemical called
adenosine triphosphate (ATP) their energy
During the process of "burning" ATP, your
muscles need three things:
• They need oxygen because chemical
reactions require ATP and oxygen is
consumed to produce ATP;
• They need to eliminate metabolic wastes
(carbon dioxide, lactic acid) that the
chemical reactions generate;
• They need to get rid of heat. Just like an
electric motor, a working muscle generates
heat that it needs to get rid of.
In order to continue exercising, your
muscles must continuously produce ATP.
To make this happen, your body must supply
oxygen to the muscles and eliminate the
waste products and heat.
If these needs are not met, then exercise will
cease – that is, you become exhausted
and you won't be able to keep going.
To meet the needs of working muscles, the
body has an orchestrated response
involving the heart, blood vessels, the
nervous system, lungs, liver and skin.
It really is an amazing system!
How to be in shape?
It’s designated as an area of activity within the gyms
The basic function is to trace a pattern of training so
as to allow a person to attain a good fitness;
For that it uses several components, and it applies
certain principles of training in order to achieve a
good and balanced body composition.
Aerobic endurance and
Strength and muscular endurance;
Good body composition, without
excess fat in terms of percentage.
Strengt training includes exercises done individually,
with free weights and specific equipment, with the
main objective of improving strength, endurance and
increase muscle mass;
The cardiovascular part is held on a treadmill, on an
‘elliptical’, a bike and others that help lose weight and
There is also the possibility of hiring a Personal Trainer
Fitness can also include gym and weight training.
However, it is also possible to be in shape through
swimming, dancing, martial arts and other
The gym includes group lessons in classrooms, such
as localized abdominals, cycling, step, etc.
The most frequent are:
Not enough stretching;
Forgetting to hydrate;
Poorly supplemented training.
Thus, the true concept of fitness encourages the
search for a balance between pleasure and
dedication, giving us a sense of wellbeing which
includes our mental and emotional health. This
helps us control the feelings and anxieties which
are part of the agitated life of modern society.
Escola Secundária do Restelo
Núcleo de Intercâmbios Europeus