BTEC A+P

Will respond in the short term by:

•  Producing more synovial fluid in the synovial joints. Makes joints more lubricated and can protect the bones.The fluid will become less viscous and the range of movement at the joint will increase.
• Increased uptake of minerals within the bones.

Increase bone mineral density and over time this will result in stronger bones which will be more resistant to the forces found in sports such as kicking, jumping or running.

Long term physical activity will increase the strength of the ligaments which attach bones at synovial joints.

Arthritus- a condition where there is inflammation within a synovial joint, causing pain and stiffness in the joint. Osteoarthritus being the most common type.

Caused by-

• General wear and tear over a long period of time. This reduces the normal amount of cartliage tissue, which may result in the ends of the bones rubbing together.  

Osteoporosis- the weakening of bones caused by a loss in calcium or a lack of Vitamin D.

Physical activity and exercise can help to prevent it by promoting increased uptake of minerals within the bones, resulting in an increase in bone mineral density.

Resistance training is a good method to prevent it as overloading the skeleton will increase bone density.

Age

Resistance training in children can cause more harm than good. A childs bones are still growing and putting too much force on them can damage the epiphyseal plates which are found at each end of the long bones. Damage to these during childhood can result in stunted bone growth.

Three main types of muscle tissue in the human body-

• Skeletal muscle- voluntary= under conscious control. Connected to the skeletal system via tendons. They contract and as  a result pull on bones to create movement.
• Cardiac muscle- involuntary. Found in the walls of the heart. Composed of special tissue that has its own blood supply. Each contraction and relaxation of the heart represent one HB.
•  involuntary. Functions under the control of the nervous system. Located in walls of digestive system.

Increased blood supply- greater demand for O and glucose in the muscles, which is met by an increase in blood supply.

Blood vessels expand to allow more blood to enter the muscles= vasodilation. Blood flow increases significantly to ensure that the working muscles are supplied with the O they need as well as to remove waste products.

Increased muscle temp- the more exercise that is done or the harder you train, the more energy your muscles need. More heat is produced.

Increased muscle pliability- the warming of muscles during activity makes them more pliable and flexible. Pliable muscles are less likley to suffer injuries such as muscle strains. Increase in pliability will improve joint flexibility as the muscles will be able to stretch furthur.

Lactate- a build up of lactic-acid which is a waste product produced during anaerobic exercise. This build up of acid in the muscle tissue will result in the rapid fatigue and will impede muscular contractions if not removed quickly.

Micro tears- muscles are put under stress to the point where tiny tears occur in the muscle fibres. These cause swelling in the muscle which causes pressure on the nerve endings and pain. Training improvements will only be made if the body has rest and time to repair these micro tears, making the muscle a little bit stronger than it was before.

Delayed onset of muscle soreness- DOMS is the pain felt in muscles 24-48 hours after taking part in strenous exercise. Caused by the microtears that occur when you exercise. Often where eccentric muscle contraction has occurred.

Training or exercising regularly over a long period of time will allow the bodys muscular system to change and adapt.

Hypertrophy- Regular resistance training where the muscles are overloaded will increase muscle size and strength. The increase in muscle size is a result of the muscle fibres becoming larger due to increases in protein in the muscle cells.

Increased tendon strength- Tendons will increase in flexibility and strength with regular exercise.

Increase in number and size of mitchondria- when muscles are overloaded as part of resistance training, the muscle fibres will become bigger. Within these muscle fibres are tiny structures called mitochondria which are responsible for energy production. Because of the increase in fibre size, there is more room for mitochondria which results in the muscles being able to produce more aerobic energy improving aerobic performance.

Increase in myoglobin stores

Increase in storage of glycogen

The body needs a constant and steady supply of glycogen in order to produce energy.As the body adapts to long-term exercise, the muscles are able to store more glycogen.

Increase in storage of fat

Fat stores produce energy through a process called aerobic glycolysis. Well-trained athletes are able to use these fats more efficiently, breaking them down into fatty acids and into energy using oxygen. This enables fats to be used as an energy source when carb becomes so scarce.

Increased tolerance to lactate:

Anaerobic training stimulates the muscles to become better able to tolerate lactic acid, and clear it away more efficiently.

Age:

As you get older muscle mass will increase. The onset of this muscle mass loss begins around the age of 50= sarcopenia. Muscles become smaller, resulting in a decrease in muscle strength and power.

Cramp:

Sudden involuntary contractio of the muscle. The sensation of muscle spasm where you have no control of the tightening of the muscle can be painful.

Nasal Cavity:

When you breathe in air enters the nasal cavity by passing through the nostrils. Hairs within the cavity filter out dust, pollen and other foreign particles before the air passes into the two passages of the internal nasal cavity. Air is warmed and mositened before it passes into the nasopharynx. A sticky mucous layer traps smaller foreign particles, which tiny hairs called cillia transport to the pharyx to be swallowed.

Pharynx=throat

A small tube fom base of skull to the level of the sixth cervical vertebrae. A passegeway for food and air so adaptations are required to prevent choking when food or liquid are swallowed.

Layrnx= voice box

Has rigid walls of muscle and cartliage. Connects the pharynx to the trachea. It extends for about 5cm from third to sixth vertebrae.

Trachea=windpipe

Denotes the start of the lower respiratory tract.

About 12cm long and 2cm in diameter. Contains rings of cartliage to prevent collapse. Flexible. Travels down neck in front of the oesophagus and branches into the right and left bronchi.

Epiglottis= Small flap of cartliage at the back of tongue. It closes the top of the trachea when you swallow to ensure food and drink pass into your stomach and not your lungs.

Bronchi- branch off the trachea and carry air to lungs. Once inside the lungs, each bronchus subdivides into lobar bronchi, three on the right and two on the left.

Bronchioles-small airways that extend from the bronchi and connect the bronchi to small clusters of thin-walled air sacs known as alveoli. Bronchioles are about 1mm in diameter and are the first airway branches of the respiratory system that do not contain cartliage.

Alveoli= sacs at the end of each bronchiole. Responsible for the transfer of oxygen into the blood and the removal of waste such as C02=gaseous exchange. Surrounding each alveolus is a dense network of capillaries to facilitate the process of gaseous exchange.

Diaphragm- a flat muscle that is located beneath the lungs within the thoracic cavity- and seperates the chest from the abdomen. The diaphragm is one of several components involved in breathing, which is the mechanism of drawing air- into the body. 

Thoracic cavity- the chamber of the chest that is protected by the thoracic wall- the ribcage. 

Internal intercostals- lie inside the ribcage. They draw the ribs downwards and inwards, decreasing the volume of the chest cavity and forcing air out of the lungs when breathing out. 

External intercostals- lie outside the ribcage. They pull the ribs upwards and outwards, increasing the volume of the chest cavity and drawing air into the lungs when breathing in. 

Breathing or pulmonary ventilaton is the process by which air is transported into and out of the lungs, and it can be considered to have two phases.

Imspiration- breathing air into the lungs. The intercostal muscles between the ribs contract to lift the ribs upwards and outwards, while the diaphragm is forced downwards. Causes a drop in pressure within the lungs to below atmospheric pressure, which encourages air to be drawn into the lungs. 

Expiration- intercostal muscles relax. The diaphragm relaxes moving upwards and the ribs move downwards and inwards. Pressure increases and air is expelled out of the body. 

During exercise, greater amounts of O are required so the intercostal muscles and diaphragm must work harder. This results in an increase in the breathing rate and an increase in the force of the breath. 

Neural control

Inspiration= active process- as the diaphragm muscle is actively contracting which causes air to enter the lungs.

Expiration= passive process- as the diaphragm muscle relaxes to allow air to exit the lungs. 

Process is controlled by neurons in the brain stem. 

Sensors that respond to chemical fluctuations and are called chemoreceptors. 

Chemorecptors-found in the medulla and in the aortic arch and carotid arteries. They detect changes in blood and CO2 levels as well as changes in blood acidity and send signals to the medulla that will make changes to breathing rates. 

Gaseous exchange- proceess where one type of gas is exchanged for another. In the lungs, gaseous exchange occurs by diffusion between air in the alveoli and blood in the capillaries surrounding their walls. Delivers O from the lungs to the bloodstream and removes C02 from the bloodstream to the lungs. 

Occurs readily by simple diffusion across the respiratory membrane. Blood entering the capillaries from the pulmonary arteries has a lower O concentration and a higher C02 concentration than the air in the alveoli. O diffuses into the blood via the surface of the alveoli, through the thin walls of the capillaries, through the red blood cell membrane and latches onto haemoglobin. 

Lung volumes 

When exercising, breathing will become deeper and more frequent to cope with the demands that exercise puts on the body.

Respiratory rate- amount of air you breathe in one minute. 

Tidal Volume- the volume of air breathed in and out with each breath. Under normal conditions this represents about 500cm3 of air breathed both inhaled and exhaled. 

Vital capacity- amount of air that can be forced out of the lungs after maximal inspiration. 

Inspiratory reserve volume- additional air that can be used in additon to the normal tidal volume. 

Expiratory reserve volume- amount of additional air that can be breathed out after normal expiration. 

Total lung volume- the total lung capacity 

Increased breathing rate- Muscles demand more O and increase in CO2 production stimulates faster and deeper breathing.

Anticipatory rise- a minor rise in breathing prior to exercise.

After several minutes of aerobic exercise, breathing continues to rise though at a slower rate and it levels off if the exercise intensity remains constant. If the exercise is maximal, the breathing rate will continue to rise until exhaustion. After exercise, the breathing rate returns to normal, rapidly to begin with and then slowly.

Increased tidal volume- to allow more air to pass through the lungs. Elevated by aerobic and anaerobic exercise.

The respiratory system undergoes specific adaptations in response to an organised and regular training programme.

Increased vital capacity- increases in response to long term physical training to provide an increased and more efficient supply of O to working muscles.

Increased strength of respiratory muscles- the diaphragm and intercostal muscles increase in strength, allowing for greater expansion of the chest cavity. This will mean that it is easier to take deeper breaths as the stronger and more pliable muscles will allow the chest cavity to expand further.

Increase in O and CO2 diffusion rate- an increase in diffusion rates means that you can train for longer and harder, as the muscles will be supplied with more O and the increased CO2 will be removed more quickly.

Asthma- a common condition where the airways of the repsiratory system can become restricted. This makes it harder for air to enter the body, resulting in coughing, whezzing or shortness of breath.

During normal breathing, the bands of muscle that surround the airways are relaxed and air moves freely. However, asthma makes the bands of muscle contract and tighten so that air cannot move freely in or out of the body.

This has a negative impact on performance as people with the condition wont be able to get enough O into the lungs to supply the muscles. Regular exercise will strengthen the respiratory system and help prevent asthma.

Lungs have to work harder causing:

• Shortness of breath
• Dizziness
• Headaches
• Difficulty in concentrating.                                            Decreased availability of O can lead to hypoxia- occurs when the body has insufficient access to O. To cope, you must breathe faster and deeper. Respiratory system will adapt over time so that it can cope wiith the decrease in O. Lungs will acclimatise by becoming larger enabling them to take in more O. Body will produce more red blood cellls and capillaries, enabling the lungs to oxygenate more efficiently.