stress

Managing Stress

Factors that create stress for me are money worries such as debts and work I worry about money and all the bills that need paying every month and because of these bills and debts I have to work extra shifts to ensure I have enough money to pay them, working extra shifts then causes problems with my partner and I as we don’t see each other as much as we’d like. At the moment the access course is also adding to my stress as I am a night carer and work full time plus I have to find time to complete course work at home and spend the day on the access course on Friday’s.

I know that I am stressed as I get very agitated and upset, crying a lot which then makes me smoke more as I feel less agitated when I smoke. I also get angry and usually take my anger out on my partner and shout at him not really for any reason. Then I feel bad for shouting at him and then get upset again.

When I feel stressed I like to take long walks or have a soak in the bath.
Long walks in the country side seem to clear my head and allow me to have some time on my own to think about things and to calm myself down. I think the exercise I get with walking also makes me feel better.
Taking some time out just for me is a nice way of relaxing to try and forget about what has been bothering me.

The Body and Exercise

Effects of Exercise on the Body

When doing strenuous exercise and training such as weight training several changes happen in the body

• Breathing becomes quicker and deeper


• Heart beats faster


• Skin temperature rises and sweat is produced to cool the body down


• Muscles begin to ache

With long term exercise and training the body becomes more effective

• Muscles become stronger


• Heart becomes stronger


• Lungs become stronger and lung capacity increases


• Oxygen debt reduces


• Fat will turn into muscle


• More flexible and more control over movements


• Co ordination will improve


• Length of time taken to get from exercise to state of rest will improve

Effects of Exercise on the Muscles and Bones

sprinting
Running involves the hip, knee and ankle joints. the bones from the hip involved are the femur and the pelvic girdle which is a ball and socket joint, the muscles used when contracting are the gluteal muscles and the hamstrings. the muscles used when not contracted are the iliopsoas.


The bones of the knee involved are the femur and the tibia which form a hinge joint, the muscles used when contracting are the quadriceps, when not contracting the muscles used are the hamstrings.


The bones in the ankle involved are the tibia and calcaneus these form a modified joint. each of these joints produce two actions one when the leg contracts with the ground and one when the leg is not contracted with the ground. the muscles used when contracted are the gastrocnemius and when not contracted the muscle used is the Tibialis anterior.




Throwing

Throwing consists of two phases the preparatory phase and the throwing phase, the two joints involved are the elbow and the shoulder.


The elbow is a hinge joint formed by the ulna and the humerus the muscles used are the triceps branchii.

The shoulder is a ball and socket joint formed between the humerus and the scapula the muscles used are the anterior and posterior deltoids and pectoralis major.




kicking

Kicking involves the hip, knee and ankle joints.


The bones of the hip involved in kicking are the femur and pelvic girdle these form a ball and socket joint the muscles used are the gluteal muscles.


The bones of the knee involved are the femur and tibia these form a hinge joint this action uses the hamstring muscles


The bones of the ankle involved are the tibia and calcaneus these form a modified joint, the muscles used are the gastrocnemius.



references

cgp movement analysis handout

The Heart

The Heart

The heart is a cone shaped muscular pump which pushes blood around the body, it is divided into 4 chambers the atria which are the upper chambers they receive blood that is returning to the heart, and the ventricles which eject blood into the arteries.

The four main chambers of the heart are

• The right atrium (RA)
  
• The right ventricle (RV)
  
• The left atrium (LA)
  
• The left ventricle (LV)
  

It is essential that blood flows round the body in the right direction so the heart includes a series of valves.

• The Tricuspid valve this separates the right atrium from the left ventricle
  
• The Pulmonary valve separates the right ventricle from the pulmonary artery
  
• The Bicuspid valve this separates the left atrium and the left ventricle
  
• The Aortic valve separates the right ventricle from the ascending aorta
  

The wall of the heart consists of three layers

• Epicardium a thin outer layer which makes the surface of the heart smooth and slippery in texture
  
• Endocardium the smooth inner lining of the heart
  
• Myocardium makes up the bulk of the heart and is responsible for the heart pumping it is made of strong cardiac muscle fibres which are connected by electrical synapses that allow muscle actions to spread from fibre to fibre.

the cardiac cycle

The cardiac cycle describes the complete round of cardiac systole and diastole with intervals between,
Systole is a period of ventricular contraction
Diastole is a period of ventricular relaxation
Blood flows from an area of high pressure to an area of low pressure

Atrial systole
The heart is full of blood and the ventricles are relaxed
Both the atria contract and blood passes down the ventricles
The atrio ventricular valves open due to blood pressure
70% of the blood flows passively down to the ventricles so the atria do not contract a great amount.

Ventricular systole
The atria relax
The ventricle walls contract forcing the blood out
The pressure of the blood forces the atrio-ventricular valves to close which produces the lub sound
The pressure of blood opens the semi lunar valves
Blood passes into the aorta and pulmonary arteries

Diastole
The ventricles relax
Pressure in the ventricles falls below that in the arteries
Blood under high pressure in the arteries causes the semi lunar valve to close which produces the second heart sound ‘dub’
During diastole all the muscles in the heart relax
Blood from the vena cava and pulmonary veins enter the atria
The whole cycle begins again

electrical activity in the heart

The heart constantly generates a sequence of electrical activity with every single heart beat, it has a natural pacemaker that regulates the pace and rate of the heart, this sits in the upper portion of the right atrium and is a collection of specialised electrical cells known as the sinus or sino-atrial (SA) node
As the SA node fires, each electrical impulse travels through the left atrium this electrical activity causes two upper chambers of the heart to contract, the electrical impulse then moves to the area known as the atrio-ventricular (AV) node this sits just above the ventricles. The electric impulse is held here for a brief period to allow the right and left atrium to empty its blood contents into the two ventricles. The electrical impulse then travels through both. The electrically stimulated ventricles then contact and blood is pumped into the pulmonary artery and aorta.

the cardiovascular system and exercise
exercise places an increased demand on the cardiovascular system, oxygen demand by the muscles increases greatly, more nutrients are used and temperature rises. When exercising muscle cells need more oxygen so the cardiac output increases to supply the demand. Heart rate is controlled by the cardiovascular centre in the medulla of the brain. nerve impulses are sent from the cardiac centre to the SAN these nerve impulses speed up or slow down our heart rate. When exercising If blood pressure becomes too high the pressure receptors send impulses to the cardiovascular centre this then sends impulses to the SAN to slow down the heart rate. If the pressure becomes too low the pressure receptors send impulses to the SAN to speed the heart rate up.

The Structure Of Arteries, Veins, Capillaries, and Arterioles

Blood circulates around the body through three kinds of blood vessel: veins, arteries and capillaries the heart pumps the blood through the blood vessels to enable food and oxygen to get to all the cells in the body.
Arteries carry blood away from the heart and to the body cells they divide into smaller vessels called arterioles.
Arterioles divide into microscopic vessels called capillaries.
Capillaries join up to form veins.
Veins return the blood to the heart.

Arteries have a thick wall with an outer layer of fibrous muscle and a thick layer of elastic tissue and smooth muscle there is then a thin layer of folded endothelial tissue when the ventricles contract, blood enters the arteries at high pressure which stretches the endothelium and the elastic walls. When the ventricles relax the artery wall keeps the blood pressure up, if the blood pressure drops too much between heartbeats organs such as the kidneys would not function,

Arterioles are tiny branches of arteries that lead to the capillaries they regulate blood flow by constricting and dilating this is done by the control of the sympathetic nervous system. Arterioles are the main regulators of blood pressure and blood flow.

Capillaries are tiny blood vessels their walls are only a cell thick which enables materials such as oxygen, water, salts, and carbon dioxideto exchange between the contents of the capillaries and the tissue surrounding them. There are capillaries in most organs and tissues in the body the capillaries are supplied with blood by arterioles and drained by venules.
A venule is a small blood vessel which allows deoxygenated blood to return from the capillary bed to a larger vein.

Veins consist of 3 layers of tissue that are thin and less elastic than arteries, veins have valves that help blood to return to the heart and prevent it from flowing backwards, blood flow though veins is helped by muscle contraction for example when a muscle contracts it bulges and presses on the walls of the veins which pushes blood to the vein when the muscle relaxes the valve closes this helps the blood return to the heart.





references
cgp handout arteries and veins
cgp handout the heart and blood vessels
http://www.youtube.com/watch?v=PgI80Ue-AMo

The Roles of the Nervous System

The diaphragm is supplied with spinal nerves from segments c3 c4 and c5 the intercostals muscles are supplied by the thoracic spinal nerves t1 to t12 the nerves of the diaphragm lead from the brain stem and down the spine they run back to neurones in the medulla oblongata which are known as the respiratory centres. These in turn are connected to a second respiratory centre in the pons which enables automatic breathing, there are two recognised centres in the pons the pneumotaxic and the apneustic centres, these two areas are also involved in automatic breathing, if we consciously hold our breath then these centres would override it by the cerebella cortex, the cerebella cortex has a direct line to the respiratory muscles through the relevant neurones.

Built into the pons is a standard rate of breathing this is variable, there are connections between the pons and medulla, in the aortic arch there are sensors which detect the oxygen and carbon dioxide concentration of blood.

references

cgp respiratory system handout

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/autonomic.gif

The Respiratory System

Respiration is essential to human life; it provides oxygen and the energy which keeps us alive

The respiratory system supplies the blood with oxygen the blood then carries oxygen to all parts of the body, the respiratory system takes oxygen in through breathing (pulmonary ventilation) we inhale oxygen and exhale carbon dioxide through the nose (diffusion of gases) this process takes place between 15 and 25 times each minute.

Oxygen is inhaled through the nose and to the pharynx where the air is then passed through the larynx and to the trachea the bronchus then leads away from the trachea and to the lungs, this single bronchus splits into smaller bronchi which are narrow airways which make up the lungs known as the bronchial tree these supply air to a single lobe and then again to tertiary bronchioles which each supply a single part of that lobe. These tertiary bronchioles lead to the alveoli.
Alveoli is a thin walled sac with a moist inner surface that allows gases to be exchanged between the air and blood. Alveoli in a cluster look like a bunch of grapes there are lots of them so there is a greater surface area for the gas exchange to take place. We breath in around 21% of oxygen but we only breath out around 16% the remaining 5% passes through the walls of the alveoli through the thin walls and capillaries and into the blood. At the same time carbon dioxide passes in the opposite direction.

The respiratory system and exercise

In the short term the body has a number of responses to exercise such as:
Tidal volume increases
Breathing rate increases and becomes deeper and more regular
Heart beat increases supplying the demand for O2 in the working muscles
Gaseous exchange in the alveoli increases

The more muscles contract the more energy they use, to replace the energy the body needs to do more aerobic respiration, it needs to take more oxygen and breathe out more carbon dioxide. The body does this by increasing the breathing rate; this is a physiological adaptation that helps the body cope with exercise.
During exercise carbon dioxide levels rise these decrease the Ph levels in blood, there are receptors in the medulla, aortic bodies and carotid bodies called chemo receptors these detect changes in the ph of blood, if they detect and increase or decrease they send a signal to the medulla to send more frequent nerve impulses to the intercostals muscles and diaphragm, this then increases the rate and depth of breathing. Gaseous exchange then takes place co2 levels drop and extra o2 is supplies for the muscles.










references
cgp powerpoint respiratory handout
www.youtube.com
cgp handout physiological adaptations

Plasma and Red Blood cells

Plasma

blood is a specialised tissue consisting of several types of cell suspended in a fluid called plasma.
the cellular constituents consist of Red blood cells, white blood cells and platelets.
plasma is a clear liquid which is made up of mainly water, sugar, fat, protein and salt solution it carries the red blood cells white blood cells and platelets around the body. 55% of our bloods volume is made up of plasma about 95% of it consists of water. plasma allows blood to navigate fast moving substances in solution and slow thicker substances in suspension. as the heart pumps blood to cells throughout the body plasma brings the nourishment to them and removes any waste products.
proteins make up 6-8% of the blood they are equally divided between serum globulins and serum albumin, serum albumin is made in the liver and it binds small molecules for transport through the blood and helps maintain the osmotic pressure of the blood.
other proteins are the serum globulins, alpha globulins the proteins which transport thyroxin and retinol, beta gobulins is the iron transporting protein to be transfered.
gamma gobulins are the main antibodies which become more abundent following infections and immunisations.


red blood cells

Red blood cells are made in the red bone marrow such as the vertebrae, cranial bone ends of the femur and humerus bone and live for around 120 days they are biconcave in shape and are very flexible with an ability to twist and bend through blood vessels they are only 1/12.000 of an inch in size. The blood contains 25 trillion red blood cells and has to replace them at around 3 million per second.
The reason they are known as red blood cells is because of a substance called haemoglobin, haemoglobin consists of protein and iron pigments and when combined with oxygen their colour becomes bright scarlet. Red blood cells assist with the transportation of oxygen, each molecule binds four oxygen molecules where ox haemoglobin forms. (Hb + 402= Hb08) the oxygen molecules are then carried to individual cells and released in the body tissue. Carbon dioxide then diffuses from the tissue into the red blood cells it then combines with water to form carbonic acid this is a slow reaction but if enzyme carbonic anhydrase is present it is a quicker process.


references
cgp blood powerpoint handout
www.texasheartinstitute.org/HIC/anatomy/blood.cfm