Please enable JavaScript.
Coggle requires JavaScript to display documents.
Short Term Effects Of Exercise - Physiology (Cardiovascular System…
Short Term Effects Of Exercise - Physiology
Cardiovascular System
Cardiac Cycle
When the body detects an increase in exercise intensity, the cardiac cycle must respond accordingly. It achieves this by speeding up to meet the demands of the exercise.
Heart Rate Increases
Blood Pressure Will Rise
Amount of blood filling atria + ventricles increase
Blood will be diverted to skeletal muscles that require necessary increase in nutrients + oxygen
Remove waste products such as carbon dioxide
Anticipatory Increase In Heart Rate
Anticipatory increase in heart rate occurs before the start of exercise. Heart rate can be changed by neurotransmitters such as adrenaline and noradrenaline released from the brain. Therefore before exercise the heart rate increases and blood flow increases too.
Cardiac Output
The volume of blood pumped out of the heart in 1 minute. It is expresses as Q and equal to heart rate multiplied by the stroke volume. Cardiac output may reach up to 30 litres per minute during extreme exercises.
Diffusion Rate
During exercise, diffusion rates increases to allow more oxygen movement from the capillaries to the working muscles, while carbon dioxide is exchanged into the blood for exhalation. The more you exercise, the more efficient this process becomes so that with long term aerobic training your body becomes more efficient at allowing oxygen and carbon dioxide to diffuse.
Stroke Volume
This the amount of blood pumped by the left ventricle in one contraction. During exercise, stroke volume increases progressively and gradually levels off at a higher level until exercise has ended. During max exercise stroke volume will not increase.
Heart Rate
Heart rate changes according to the body's needs. It increases during exercise to deliver extra oxygen to tissues and remove carbon dioxide. Heart rate is controlled by sinoatrial node (SAN). When you exercise information is communicated and the heart adapts accordingly. During long term exercise the resting heart rate decreases and during short term exercise the heart rate will increase.
Changes In Blood pH
The pH of blood is generally between 7.2 and 7.5 indicating a very weak alkalinity. As we exercise we go to more acidic this is due to the inclusion of waste products such as carbon dioxide in the blood due to exercise intensity
Arteriovenous Oxygen Difference (a-VO2 diff)
Arterial blood- Bright red due to higher concentrations of oxygen.
Venous Blood- Darker red than arterial blood due to high concentrations of carbon dioxide.
Arteriovenous oxygen difference is the difference in the oxygen content between arterial and venous blood.
Exercise leads to an increase in the difference.
Endocrine System
Adrenaline
Anticipatory Rise.
Secreted by the adrenal glands, it increases heart rate, breathing rate and metabolic rate and improves the force of muscles actions which will delay the onset of fatigue.
Vasoconstriction and vasodilation.
Noradrenaline
Released predominately from the ends of sympathetic nerve fibres and that acts to increase the force of skeletal muscle contraction and the rate + force of contraction of the heart released predominately from the ends of sympathetic nerve fibres and that acts to increase the force of skeletal muscle contraction and the rate + force of contraction of the heart.
Cortisol
This is associated with stress. Cortisol increases blood sugar levels, suppresses the immune system and aids the metabolism of macro-nutrients.
Oestrogen
This is the primary female sex hormone which is known to inhibit bone resorption.
Human Growth Hormone
This is secreted by the pituitary gland which stimulates general body growth and the lengthening of bones in particular.
Testosterone
The primary male sex hormone involved in the development of muscle tissue and muscular strength, testosterone increases the number of neurotransmitters which will encourage muscle tissue growth. Testosterone also increases levels of human growth hormone (HGH) which makes the appropriate type of exercise to promote the building of muscle tissue.
Muscular System
Muscle Fibre Recruitment
The recruitment of muscle fibres during exercise do follow a specific pattern. First slow twitch (Type 1) muscle fibres are brought into action, then fast twitch muscle fibres (First Type IIa and then Type IIx). The level of recruitment is generally determined by the demand placed on the muscle.
Micro-Tears
Every muscle in the body is made up of hundreds of thousands of tiny fibres.
During exercise muscle fibres will contract and relax against each other which will result in microscopic tears to the fibres.
When you rest after the activity your body will heal and then uses protein to fill the gaps in the tears, resulting in extra strength, depending on the exercise type there could be an increase in muscle size.
Blood Flow To Working Muscles
The body will send blood to where it is needed. This redistribution of blood is achieved primarily by vasoconstriction (reduction in the diameter of blood vessels) and vasodialation (expansion in the diameter of blood vessels) which are regulated by hormones or chemicals also known as vascular shunting.
Temperature
During exercise all muscles require energy which is gained from fuels such as carbohydrates and fats.
One of the products is heat. As the muscles warm up the blood circulating through the muscles is also warmed which will result in a rise in the body's temperature.
The amount of heat your muscles produce is related to the amount of work they perform- the more intense the exercise the more heat they will produce.
Respiratory System
Breathing Rate
A minor increase in breathing rate before exercise is known as an anticipatory rise. However when exercise begins there is an immediate and greater increase in breathing rate due to receptors in the muscles and joints.
After several minutes of aerobic exercise breathing continues to rise at a slower rate levelling off until exercise ends.
Respiratory Muscles
During exercise, forced breathing is used. This differs from normal breathing because during expiration the internal intercostal muscles contract moving the ribs and sternum upwards and outwards forcibly.
The abdominal muscles also contract increasing the pressure of the abdominal cavity, helping the diaphragm to rise more forcibly. During exercise the muscles involved in the breathing process can use up to 10% of the bodys total oxygen uptake.
Tidal Volume
This increases dramatically during exercise due to the body's demand for more oxygen and/or the need to offload increased levels of carbon dioxide.
Trained athletes achieve the required alveolar ventilation by increasing tidal volume and only minimally increasing breathing rate.
Minute Volume
At a low to moderate exercise intensity, tidal volume and breathing rate increase proportionally. However at a high exercise intensity tidal volume reaches a peak so any further increase in minute volume requires an increase in breathing rate.
Minute volume is measure in litres per minute and is calculated by multiplying tidal volume by breathing rate.
Factors Affecting Dissociation (Respiratory)
Carbon Dioxide Concentration- The higher C02 concentration in tissue the less the affinity of haemoglobin for 02 so the harder the tissue is working the more 02 is released.
Energy Systems
ATP-PC
ATP and Creatine Phosphate make up the ATP-PC system. PC is broken down, releasing both energy and a phosphate molecule (which is then used to rebuild ATP). The enzyme that controls the breakdown of PC is called creatine kinase.
The ATP-PC system can operate with or without oxygen, but because it does not rely on the presence of oxygen it is anaerobic. During the first five seconds of exercise regardless of intensity the ATP-PC system is relied on almost exclusively.
The ATP-PC system can sustain all out exercise for 3-15 seconds. If the activity continues beyond this period the body must rely on an additional energy system to re synthesise ATP.
Aerobic
The aerobic energy system uses carbohydrates, fats and proteins extracted from the diet to re synthesise ATP. This system produces more ATP than the ATP-PC or the lactate system, but does so at a slower rate and is therefore less suitable for intense exercise. The aerobic system consists of three stages, each of which produce ATP.
Lactate
Glycolysis is the term used to describe the breakdown of glucose. It consists of a series of enzymatic reactions. The end product of glycolysis is pyruvic acid which is used in a process called the Krebs cycle or converted into lactic acid.
Skeletal System
Osteoclast Activity
Bone is a dynamic tissue. It is constantly reshaped by osteoblasts. In return osteoclasts break down the tissue which will allow new growth.
During midlife, osteoblast and osteoclast activity is in balance, however as the body ages osteoclast activity increases which breaks down bone tissue to release calcium and other minerals into the blood stream.
Research suggests weight bearing exercise stimulates the activity of osteoblasts and suppresses osteoclast activity which will maintain a healthy bone density.
Synovial Fluid
Synovial fluid is thick, straw- coloured liquid that acts as a lubricant and is found primarily in the cavities of synovial joints.
Exercise increases the amount of synovial fluid, decreasing its viscosity keeping joints healthy while stopping cartilage from drying out.
Research suggests exercise also increases the range of movement at the joints as more synovial fluid is released into them.