The Concepts of Fitness

Fitness is defined as a condition of good health and well being and, more importantly, the capacity to do typical parts of daily activities, jobs and sports. Physical fitness usually requires adequate rest, proper nutrition and, in cases of extreme sports or work, adequate training. A person’s level of fitness depends on many factors including the quality of his lifestyle and the type of exercises he performs on a regular basis. A healthy lifestyle includes a balanced diet, regular participation in physical activities, sufficient sleep and the right kinds of exercises and activities.


An important factor in an organism’s fitness level is its ability to adapt to changes. The definition of adaptation can be described as an effective and efficient response to a threat or danger. Therefore, in order to be fit, the organism has to change, grow or adapt. The definition of ecological fitness considers adaptation as the normal process that happens when an organism is changing or growing. When this happens, the organisms adapt by growing in size or acquiring new characteristics.

Fitness is also defined by some researchers as a complex process that involves both genetic and physical factors. It is an umbrella term that is used in a number of scientific studies and various disciplines. Most researchers agree that there are two general kinds of fitness: positive and negative. Positive fitness is associated with strength, power and stamina, whereas negative fitness occurs when the body lacks muscular strength, power and stamina. Some researchers use the word “tautology” to define fitness differences.

Fitness is a complex trait and differs between individuals. Individual traits are those which vary from one person to another. There are several theories that explain the concept of individual fitness, including heredity, natural selection and evolution, favorable versus unfavorable environments, and culture and nationality. The best definition of trait fitness defines it as a genetic and physical variable that can be manipulated.

This definition of fitness helps us better understand and appreciate the fact that fitness varies among organisms. There are many theories about the nature and definition of fitness. A few of the most popular explanatory theories natural selection and evolution are considered the most valid. The other theory of natural selection is considered the most controversial. The current theory of ecological fitness is an umbrella term that includes adaptive, directional, and invasive fitness.

Most people have a general idea of the concepts of fitness. They know the difference between adaptive and invasive fitness. They also understand that some fitness differences are universal and others are individualized. They may not know that some individuals possess characteristics of more than one type of fitness. Those who don’t understand the concepts of fitness may be at risk for health problems. Thus, learning about fitness helps them live healthier lives and avoid serious health hazards.