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​Remember from previous unit that **VO2max** is the amount of oxygen that can be taken in, and used, per kilo of bodyweight. Within the world of sports, fitness is achieved as a result of maximising one or more fitness components as determined by the nature of the sport. No fitness component is of a higher standing or importance than another in general terms, only in sporting specific environments.

__Components of Physical Fitness:__

The components of fitness relate to the requirements of a given sporting activity and can help to explain success or failure in sport.

There is a distinction between **HEALTH RELATED** and those that are **SKILL RELATED** although both of them will affect performance in sport. Health related factors are **physiologically** based and determine the ability of an individual to meet the physical demands of the activity. The skill related factors are based on the **neuro-muscular system** (last unit) and determine how successfully a person can perform a specific skill.

__Health related Components of Fitness__


 * Strength** is the ability of the body to apply a force. This is the maximum amount of force that can be developed in a muscle or group of muscles during a single maximal contraction.

//Absolute Strength://** The maximum amount of force that can be exerted one time, regardless of body weight or size. Sport example would be rugby where a tackle is made with the greatest force possible. source
 * STRENGTH
 * //Dynamic Strength://** This is the body's ability to exert signifant muscular force repeatedly. An example of this would be a long distance rowing.
 * //Elastic Strength://** This is the ability to exert a force quickly (strength x speed)


 * //Explosive Strength://** The ability to exert maximal force quickly or in one action. A javelin thrower would require both elastic strength and explosive strength


 * //Relative Strength://** The maximum amount of force that can be exerted in proportion to body weight. This is important for someone who is doing Judo, as they need to exert the maximum amount of force within his weight category


 * //Strength Endurance: (localized muscular endurance)//** This is the ability of the muscle to resist fatigue while exerting a force or performing a repeated action over and over.


 * //Static Strength://** This is the ability to exert a sustained force without significant movement.

__Factors which affect Strength__

Strength is directly related to the cross-sectional area of the muscle tissue as well as the type of muscle fibre. White fast twitch muscles can generate greater forces that their red slow twich counterparts. Age has an affect on the body's ability to develop strength, with the early-mid twenties being the optimal time. As the body ages, less protein becomes available for muscle growth, and the stress/anaerobic training is inappropriate for older athletes Gender is not an issue when it comes to the cross sectional area of muscle tissue - men and women are equal int his respect. It is the greater fat content of women and the higher testosterone levels in men that can create the difference in the cross sectional area of muscle.

__Measuring Strength__
 * Dynamometers** : These give an objective measure of the force generated within various muscles or muscle groups. The easiest test is the **handgrip dynomometer** which measures grip strength generated by the muscles in the forearm. Advantages are that it is simple and objective, when done three times in each hand. The disadvantages lie in the validity of the test, since it only indicates muscular strength in the forearm.
 * Repetition Maximum Test (IRM):** This assesses the maximal force a subject can lift in one rep using free weights or other gym equipment. This is easily done with most gym equipment but it carries with it a high threat of injury and it can be difficult to isolate certain muscles.

__ Measuring Muscular Strength Endurance __ Muscular strength endurance is the ability of a muscle or group of muscles to sustain a repeated contractions against a resistance for an extended period of time. The slow twitch fibres ensure that a rich supply of blood is available to facilitate aerobic energy. This enables muscles to repeat the muscular contraction without the build up of lactic acid. Muscular endurance relies on the body's ability to efficiently produce energy under both aerobic and anaerobic situations and is able to buffer lactic acid build up.

THis can be measured simply with the NCF abdominal conditioning test with the tape, stopwatch and gymmat. The advantages in this test is that it is easy to administer with little equipment, can be done in large groups and the abdominal muscles are easily isolated. However correct technique is required to complete the test accurately.

//Aerobic Endurance://** This is the ability of the aerobic pathway to meet the needs of an activity. Within the context of sport and fitness aerobic activity is considered to cover any intensity threshold below an individuals anaerobic threshold.
 * ENDURANCE


 * //Muscular Endurance://** This is the ability of the muscle to resist fatigue


 * //Cardiovascular Endurance://** This is the ability of the heart, blood and blood vessels to work collectively to perform their function of fulfilling the needs of the cells in the body, by delivering oxygen and removing waste. The measure of this fitness component is the ability to perform this over an extended period of time. It is not lung capacity by cardiovascular fitness that determines an athletes fitness.


 * Maximal Oxygen Uptake (VO2Max) and the anaerobic threshold (OBLA)**

Maximal oxygen uptake can be defined as the maximal amount of oxygen that can be taken in, transported and consumed by the working muscles per minute. It is largely dependent upon the difference in oxygen content of inspired and expired air.

When exercise commences, the volume of oxygen increases sharply at first, and then levels out into a steady state. THis steady state in oxygen consumption represents a balance between the energy demands of the muscle and the amount of oxygen supplied to the muscle to meet these demands. At this steady state, an athlete should be able to continue exercising for a long period of time, theoretically until his energy stores of glycogen and fat are depleted. If the terrain changes, then the oxygen consumption must increase in order to meet the increased energy demands.

Steady state occurs when energy demands are met by oxygen supply. If the terrain increases once more, the consumption will again have to increase until the steady state is reached once again. If the intensity continues to increase oxygen consumption will continue to increase until the body cannot consume any more oxygen. This point is known as the **maximal oxygen uptake or V02max**

If the body reaches this point, any increase in intensity must be met by by the body increasing the overall energy expenditure. The additional energy expenditure has to be generated by **anaerobic means.** This can cause severe problems for the athlete since anaerobic respiration causes the onset of lactic acid and ultimately fatigue. The only way to reduce the onset of lactic acid is to reduce the level of intensity so that oxygen consumption falls below the point of V02max. However this may decrease all chances of a successful performance.

The point at which lactic acid starts to accumulate is known as the anaerobic threshold, or **onset of blood lactate accumulation (OBLA).** It is measured as the percentage of V02max reached before lactic acid starts to accumulate.

[] (This is a useful summary of anaerobic energy respiration)

__ Factors affecting aerobic performance __

Physiological factors that determine aerobic performance include the possession of a large proportion of slow twitch muscle fibres, many mitochondria and large myoglobin sotres. These in turn allow for the production of large amounts of energy via the aerobic pathways. The single most influencing factor is the maximum amount of oxygen that an individual can consume (VO2max). This has a genetic component and is influenced little by training.

Genetics Age (Vo2max decreases approximately 1% per year after 25) Training - Undertaking the right training can improve V02max by 10-20% Gender - Women tend to have lower Vo2max scores, between 15-30% Body Comp. - Vo2max is thought to decrease as body fat percentage increases Lifestyle - smoking and poor diet lead to decreases in V02max Exercise testing has to be appropriate the the type of athlete being tested

Measuring Aerobic Capacity ​

NCF Multistage Fitness Test

20m Track CD/Tape Tape Player Tape Measure and Cones

Subjects are required to run the 20m course in time with the beeps on the CD. The difficulty increases as each level goes. Withdrawal from the test occurs when you can no longer keep pace with the beeps

This is a very easy test to administer and evaluate using the tables. Large groups can be done at one time and it requires limited equipment However this is a maximal test and relies on motivation levels. This is also only a prediction of VO2max rather than a measure of it. Some athletes such as swimmers may not perform as well on the land as they might in the water.

PCW 170 Test (Physical Work Capacity)

This is a sub maximal test. Subjects complete three workloads consecutively on a cycle ergonometer while the heart rate is monitored. The first set is when the athletes heart rate is between 100-115. The heart rate is measured each minute until the heart rate is steady. The test is repeated for 115-130 and 130-145. Each steady state and respective workload is graphed and used to predict a workload that would elicit a heart rate of 17-bpm.

This test may favour cyclists. This is only a prediction of V02max. This test is maximal so requires motivation from the participant.

This is the range of movement available at a joint. It is determined by two factors - joint structure and muscle elasticity.
 * FLEXIBILITY**

__Factors affecting flexibility__

Internal factors which can affect flexibility include: 1. The type of joint 2. The structure of the joint which limits movement 3. Elasticity of the muscle tissue 4. Elasticity of the surrounding tendons and ligaments 5. Temperature of the joint and associated tissues 6. Strength of the opposing muscle group

External Factors 1. Temperature of local environment 2. Age (reduction in mobility from the age of 8) 3. Gender 4. Clothing 5. Injury 6. Activity Level

Measuring Flexibility Sit and Reach Test

You need a sit and reach box

This is an easy test to administer and record. Lots of data available to find norms.

This however only measures flexibility in the region of the lower hamstrings and back so it cannot give an overall score for flexibility

Speed is defined as the time taken to move the body, either as a whole or a part through a movement over a pre-determined distance.
 * SPEED**

__Factors affecting Speed__

Speed tends to be genetically determined due to the physiological makeup of the muscle and as such is least affected by training and can take some time to develop. Fast twitch muscles (FTG) tend to be beneficial in activities where speed is essential, since they can release energy for muscular contraction rapidly.

Measuring Speed

30m Sprint Test

This is an easy test to administer with norm values to score against. However timings can be affected by error and the affects of weather or running surface have to be taken into account. This also does not test the speed of the body parts.

This is used to describe the percentages of fat, bone and muscle that make up the human body. We use somatotyping to determine whether a body is an ecto, endo or mesomorph (covered later).
 * BODY COMPOSITION**

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source

A useful website showing the location of the sites to take a skinfold measurement: []

Somatyping is a way of measuring body shape. Endomorphy is the relative fatness or pear shaped ness of the body Ectomorphy is the linearness of the body Mesomorphy is the muscularity of the body

It is rare that an individual is found at any extreme. Most people possess characteristics of two or all three. The contributions of each would depend on the activity.

How do we measure body fat?

1) Hydrostatic weighing - water displacement weight in a lab. 2) Bioelectrical impedence - sending an electrical current through the body to measure resistance 3) BMI or body mass index (weight in kg/height in m2) This does not differ between fat mass and muscle mass 4) Skinfold Measures - simplest

=Skill Related Components of Fitness=

//the ability to move and change direction and position of the body quickly and effectively while under control//
 * Agility**

Many factors are involved with agility including balance, coordination, speed and flexibility. Although activities can be undertaken to improve agility, development of this skill related component is limited

Agility is generally tested using the Illinois agility run.

//the maintenance of te centre of mass over the base of support. This can be while the body is static or dynamic.//
 * Balance**

There are two types of balance - static and dynamic. Static balance such as a handstand which requires the maintenance of a position. On the other hand, a rugby tackle requires the ability to stay on their feet and this is an example of dynamic balance.

The stork stand test or a balance board can be used to measure balance.

//the interaction of the motor and nervous systems and is the ability to perform motor tasks accurately and effectively//
 * Coordination**

Coordination generally requires several things to happen together. The serve in tennis would be an example. A swimmer swimming butterfly requires coordination to have the legs and arms working in sync with one another

//the time taken to initiate a response to a given stimulus//
 * Reaction Time**

Reaction time depends on the ability of the individual to process information and initiate a response by the neuro-muscular system. Reaction time can be improved by training

Power //the amount of work done per unit of time or the product of strength and speed//

Power can be thought of the ability to generate explosive strength over a short period of time. It relies on the ability of the neuro-muscular system to recruit fast twitch fibres.

A good test of power is the vertical jump test.