The 5 components of physical fitness are often used in our school systems, health clubs and fitness centers to gauge how good a shape we are truly in. The 5 components that make up total fitness are:
- Cardiovascular Endurance
- Muscular Strength
- Muscular endurance
- Flexibility
- Body Composition
Total fitness can be defined by how well the body performs in each one of the components of physical fitness as a whole. It is not enough to be able to bench press your body weight. You also need to determine how well you can handle running a mile etc.
A closer look at the individual components:
Cardiovascular endurance is the ability of the heart and lungs to work together to provide the needed oxygen and fuel to the body during sustained workloads. Examples would be jogging, cycling and swimming. The Cooper Run is used most often to test cardiovascular endurance.
Muscular strength is the amount of force a muscle can produce. Examples would be the bench press, leg press or bicep curl. The push up test is most often used to test muscular strength.
Muscular endurance is the ability of the muscles to perform continuous without fatiguing. Examples would be cycling, step machines and elliptical machines. The sit up test is most often used to test muscular endurance.
Flexibility is the ability of each joint to move through the available range of motion for a specific joint. Examples would be stretching individual muscles or the ability to perform certain functional movements such as the lunge. The sit and reach test is most often used to test flexibility.
Body composition is the amount of fat mass compared to lean muscle mass, bone and organs. This can be measured using underwater weighing, Skinfold readings, and bioelectrical impedance. Underwater weighing is considered the “gold standard” for body fat measurement, however because of the size and expense of the equipment needed very few places are set up to do this kind of measurement.
www.lifetime-fitness-routines.com
Cardiorespiratory fitness (CRF) refers to the ability of the circulatory and respiratory systems to supply oxygen to skeletal muscles during sustained physical activity. The primary measure of CRF is VO2 max.[1] In 2016, the American Heart Association published an official scientific statement advocating that CRF be categorized as a clinical vital sign and should be routinely assessed as part of clinical practice.[1]
Regular exercise makes these systems more efficient by enlarging the heart muscle, enabling more blood to be pumped with each stroke, and increasing the number of small arteries in trained skeletal muscles, which supply more blood to working muscles. Exercise improves not just the respiratory system but the heart by increasing the amount of oxygen that is inhaled and distributed to body tissue.[2] A 2005 Cochrane review demonstrated that physical activity interventions are effective for increasing cardiovascular fitness.[3]
There are many benefits of cardiorespiratory fitness. It can reduce the risk of heart disease, lung cancer, type 2 diabetes, stroke, and other diseases. Cardiorespiratory fitness helps improve lung and heart condition, and increases feelings of wellbeing.[2] Additionally, there is mounting evidence that CRF is potentially a stronger predictor of mortality than other established risk factors such as smoking, hypertension, high cholesterol, and type 2 diabetes. Recently, a new study demonstrated the levels of CRF were associated with early deaths <65 years old among recent generations. Low CRF might be emerging to a new risk factor for early death among US Baby Boomers and Generation Xers.[4] Significantly, CRF can be added to these traditional risk factors to improve risk prediction validity.[1]
The American College of Sports Medicine recommends aerobic exercise 3–5 times per week for 30–60 minutes per session, at a moderate intensity, that maintains the heart rate between 65 and 85% of the maximum heart rate.[5]
Cardiovascular system[edit]
The cardiovascular system responds to changing demands on the body by adjusting cardiac output, blood flow, and blood pressure. Cardiac output is defined as the product of heart rate and stroke volume which represents the volume of blood being pumped by the heart each minute. Cardiac output increases during physical activity due to an increase in both the heart rate and stroke volume.[6] At the beginning of exercise, the cardiovascular adaptations are very rapid: "Within a second after muscular contraction, there is a withdrawal of vagal outflow to the heart, which is followed by an increase in sympathetic stimulation of the heart. This results in an increase in cardiac output to ensure that blood flow to the muscle is matched to the metabolic needs".[7] Both heart rate and stroke volume vary directly with the intensity of the exercise performed and many improvements can be made through continuous training.[citation needed]
Another important issue is the regulation of blood flow during exercise. Blood flow must increase in order to provide the working muscle with more oxygenated blood which can be accomplished through neural and chemical regulation. Blood vessels are under sympathetic tone; therefore, the release of noradrenaline and adrenaline will cause vasoconstriction of non-essential tissues such as the liver, intestines, and kidneys, and decrease neurotransmitter release to the active muscles promoting vasodilatation. Also, chemical factors such as a decrease in oxygen concentration and an increase in carbon dioxide or lactic acid concentration in the blood promote vasodilatation to increase blood flow.[8] As a result of increased vascular resistance, blood pressure rises throughout exercise and stimulates baroreceptors in the carotid arteries and aortic arch. "These pressure receptors are important since they regulate arterial blood pressure around an elevated systemic pressure during exercise".[7]
Respiratory system adaptations[edit]
Although all of the described adaptations in the body to maintain homeostatic balance during exercise are very important, the most essential factor is the involvement of the respiratory system. The respiratory system allows for the proper exchange and transport of gases to and from the lungs while being able to control the ventilation rate through neural and chemical impulses. In addition, the body is able to efficiently use the three energy systems which include the phosphagen system, the glycolytic system, and the oxidative system.[6]
Temperature regulation[edit]
In most cases as the body is exposed to physical activity, the core temperature of the body tends to rise as heat gain becomes larger than the amount of heat lost. "The factors that contribute to heat gain during exercise include anything that stimulate metabolic rate, anything from the external environment that causes heat gain, and the ability of the body to dissipate heat under any given set of circumstances".[6] In response to an increase in core temperature, there are a variety of factors which adapt in order to help restore heat balance. The main physiological response to an increase in body temperature is mediated by the thermal regulatory center located in the hypothalamus of the brain which connects to thermal receptors and effectors. There are numerous thermal effectors including sweat glands, smooth muscles of blood vessels, some endocrine glands, and skeletal muscle. With an increase in the core temperature, the thermal regulatory center will stimulate the arterioles supplying blood to the skin to dilate along with the release of sweat on the skin surface to reduce temperature through evaporation.[6] In addition to the involuntary regulation of temperature, the hypothalamus is able to communicate with the cerebral cortex to initiate voluntary control such as removing clothing or drinking cold water. With all regulations taken into account, the body is able to maintain core temperature within about two or three degrees Celsius during exercise.[7]
See also[edit]
- Aerobic conditioning
- Central governor
- Physical fitness
- Exercise physiology
- VO2 max
References[edit]
- ^ a b c Ross, Robert; Blair, Steven N.; Arena, Ross; Church, Timothy S.; Després, Jean-Pierre; Franklin, Barry A.; Haskell, William L.; Kaminsky, Leonard A.; Levine, Benjamin D. (2016-12-13). "Importance of Assessing Cardiorespiratory Fitness in Clinical Practice: A Case for Fitness as a Clinical Vital Sign: A Scientific Statement From the American Heart Association". Circulation. 134 (24): e653–e699. doi:10.1161/CIR.0000000000000461. ISSN 0009-7322. PMID 27881567. S2CID 3372949.
- ^ a b Donatello, Rebeka J. (2005). Health, The Basics. San Francisco: Pearson Education, Inc.
- ^ Hillsdon, M.; Foster, C.; Thorogood, M. (2005-01-25). "Interventions for promoting physical activity". The Cochrane Database of Systematic Reviews (1): CD003180. doi:10.1002/14651858.CD003180.pub2. ISSN 1469-493X. PMC 4164373. PMID 15674903.
- ^ Cao, Chao; Yang, Lin; Cade, W. Todd; Racette, Susan B.; Park, Yikyung; Cao, Yin; Friedenreich, Christine M.; Hamer, Mark; Stamatakis, Emmanuel; Smith, Lee (2020-01-30). "Cardiorespiratory Fitness Is Associated with Early Death Among Healthy Young and Middle-aged Baby Boomers and Generation Xers". The American Journal of Medicine. 133 (8): 961–968.e3. doi:10.1016/j.amjmed.2019.12.041. ISSN 0002-9343. PMID 32006474.
- ^ Pollock, M.L.; Gaesser, G.A. (1998). "Acsm position stand: the recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults". Medicine & Science in Sports & Exercise. 30 (6): 975–991. doi:10.1097/00005768-199806000-00032. PMID 9624661.
- ^ a b c d Brown, S.P.; Eason, J.M.; Miller, W.C. (2006). Exercise Physiology: Basis of Human Movement in Health and Disease. Lippincott Williams & Wilkins. pp. 75–247. ISBN 978-0781777308.
- ^ a b c Howley ET, Powers SK (1990). Exercise Physiology: Theory and Application to Fitness and Performance. Dubuque, IA: Wm. C. Brown Publishers. pp. 131–267. ISBN 978-0078022531.
- ^ Shaver, L.G. (1981). Essentials of Exercise Physiology. minneapolis, MN: Burgess Publishing Company. pp. 1–132. ISBN 978-0024096210.