cardiovascularrespiratorydiet & healtheffect of exercise backcontentsnext musculo-skeletal the...
TRANSCRIPT
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
The effects of exercise on the body
EFFECTS OF EXERCISE
main listing enterquit © Copyright Ali Clarke Design 2003
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Contents – Effect of exercise
When you exercise…Exercise & respiratory system
Exercise & cardiovascular system
Exercise & musculo-skeletal system
Preventing overheating
Food & drink requirements
Smoking & fitness
Summary
main listingquit
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
When you start to exercise…
The muscles must be kept supplied with oxygen to fuel muscle contractions & allow movement
This involves taking more oxygen into the body by breathing more quickly
The heart also beats faster to pump oxygenated blood around the body more rapidly
Muscle contractions generate a lot of heat, which must be removed to prevent the body from overheating
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
When you train regularly…
Changes occur in your heart, lungs, muscles & bones as you becomes fitter
They allow your body to adapt more quickly to exercise & to make a faster recovery when you finish a training period
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Respiratory
Breathing rate
Air inhaled
Blood flow through Lungs
O2 collected
CO2 removed
Musculo-skeletal
O2 demand of muscles
Heat is generated - removed by sweating & flushing of skin
Pulse rate
Blood Pressure
Volume of blood pumped
keeps muscles supplied with O2
removes waste CO2 from muscles
Cardiovascular
Immediate effect of exercise
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Cardiovascular
Heart enlarges slightly
Red blood cells number
Artery walls elasticity
Muscles, tendons grow strength
growth of capillaries around muscles
Muscles more efficient at using O2
Ligaments strength
Range of movement in joints
Bones strength
Musculo-skeletalRespiratory
Respiratory muscles stronger & more efficient
vital capacity
growth of capillaries around alveoli
Allow you to train harder & longer
Effect of regular exercise over time
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Exercise & respiratory system
Breathing rate increases
Depth of breathing increases; i.e. volume of each breath increases (maximum possible = vital capacity)
More blood flows through the lungs
These changes allow Increased amounts of oxygen to be collected to power the
exercising muscles Increased amounts of waste carbon dioxide to be removed
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Exercise & respiratory system
With regular exercise, the respiratory muscles (diaphragm + intercostals) become stronger & more efficient at opening up the chest cavity
The vital capacity increases, so more oxygen can be taken in per breath (& more carbon dioxide can be removed)
New capillaries grow around the alveoli, allowing greater oxygenation of the blood (& faster removal of carbon dioxide)
These changes allow you to exercise more vigorously for a longer time
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Exercise & cardiovascular system
Heart beats faster; pulse rate increases
Greater volume of blood is pumped per heart beat
Blood pressure rises transiently during exercise BP drops back to pre-exercise levels when physical activity ceases
Blood is diverted away from the major body organs, except the heart & brain
Blood flow into the muscles is increased Around 20% of blood volume goes to muscles when body is at rest This rises to around 90% during vigorous exercise
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
The body produces more oxygen-carrying red blood cells
Exercise & cardiovascular system
With regular exercise, the heart grows slightly larger & its walls become thicker
This allows the heart to hold more blood & to contract with greater force
The artery walls become more elastic & prevent blood pressure rising too far during exercise
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Exercise & musculo-skeletal system
The amount of oxygen consumed by the muscles during exercise increases x70 above resting levels
As the muscles work they generate heat, warming the blood
Contracting muscles squeeze the veins & force blood back to the heart
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Exercise & musculo-skeletal system
With regular exercise, the muscles (& tendons) get bigger, allowing them to contract with greater strength
Increased numbers of capillaries grow around the muscles, so more blood can reach them with oxygen & nutrients
Muscles become more efficient at using oxygen & can work harder for longer without tiring
The body’s maximum oxygen consumption (VO2max) increases
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Exercise & musculo-skeletal system
Regular exercise also strengthens the ligaments around a joint, making the joint stronger & more stable
Stretching movements will also increase the range of movement of a joint
The articular cartilage pads that line synovial joints become thicker, & protect the underlying bones from mechanical stress
Bones become stronger
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Preventing overheating
Repeated muscle contractions release a large amount of heat energy & this must be removed quickly to prevent the body from becoming overheated
Thermal sensors in the brain monitor body temperature; when it rises too high, heat loss mechanisms are put into operation
Heat loss is achieved using two main methods; Radiation Evaporation
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Heat generated by the muscles is used to warm up the blood
Blood is then shunted through vessels close to the skin surface, which dilate to maximise the volume of blood passing through them
The skin appears flushed & feels hot
Heat radiates from the skin surface into the surrounding colder air, allowing the body to cool down
Preventing overheating: radiation
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Heat can also be lost by using heat energy to convert liquid into vapour, i.e. evaporation
This is more commonly known as sweating
Sweat is produced by sweat glands present throughout the skin, it contains mostly water plus a few salts
Rising body temperature simulates sweat glands to secrete sweat onto the skin surface, it is then evaporated using body heat energy & helps to cool the body
Excessive sweating can lead to loss of body fluid & salt, causing dehydration & cramping
Preventing overheating: evaporation
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
If the external environment is either hotter than the body or is humid, heat loss by radiation & evaporation will be severely impaired
Heat exhaustion can occur if an athlete overheats & collapses following vigorous exercise; it is often caused by dehydration
Heat stroke is a potentially fatal condition caused by prolonged overheating; it is a medical emergency
Overheating
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Food & drink requirements: water
A lot of water can be lost from the body during exercise; Increased body heat water lost as sweat Increased breathing rate water vapour lost via lungs
Dehydration can result in Thirst Headache Dizziness Muscle cramps
To avoid dehydration, it is important to take on adequate fluids during exercise
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Food & drink requirements: food
Energy for muscle activity during exercise needs to be available quickly to avoid muscle fatigue
The main source of this energy is the carbohydrate storage molecule glycogen
Body glycogen stores are limited & are depleted during exercise; they can take up to 48 hours to be replenished
Extra carbohydrate must be eaten to replace glycogen stocks during endurance events, such as football or tennis matches, distance running, etc. e.g. bananas, biscuits, jam sandwiches, dextrose tablets
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Smoking & fitness: lung function
Smoking cigarettes damages health & reduces fitness
It impairs lung function by
- Reducing alveolar function- Damaging the lining of the airways & increasing mucus production- Increasing the risk of lung infection, emphysema, bronchitis, asthma, & lung cancer
Smoking reduces vital capacity
Smoking reduces aerobic fitness
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Smoking & fitness: cardiac function
Smoking cigarettes damages health & reduces fitness
It impairs cardiac & vascular function by
Smoking reduces cardiac fitness
- Damaging the blood supply to the heart muscle- Damaging artery walls- Reducing the amount of oxygen that can be carried in the blood- Increasing the risk of angina, heart attack, & stroke- Increasing the risk of arterial disease - Increasing the risk of blood clots forming in the veins
cardiovascular respiratory diet & health effect of exercise
backcontents next
musculo-skeletal
Summary
There are many benefits of regular vigorous exercise…
Enhanced stamina & fitness
Relief of mental stress & better relaxation
Weight control
Strengthened bones & joints
Improved lung function
Reduced risk of heart & vascular diseases
Better quality of life!
end