Anaerobic and Aerobic exercise

Anaerobic exercise is when a larger amount of oxygen is used for a shorter duration, for example, sprinting. In anaerobic exercises, no oxygen is used. Because of this, the glucose isn't fully broken down to carbon dioxide and water. Instead it is converted into lactic acid while producing the energy needed for the activity. The equation for anaerobic exercise is 'glucose = energy + lactic acid'. 

Aerobic exercise is when a constant amount of oxygen is used for a longer duration, for example, marathon. Aerobic exercise involves the performer using oxygen to break down foods such as glucose. This reaction provides the energy needed for the activity and produces water and carbon dioxide as waste products. The equation for aerobic exercise is 'glucose + oxygen = energy + carbon dioxide + water'.

The main difference between aerobic and anaerobic exercises is the intensity and the duration of the exercise involved. Aerobic activities involve relatively gentle exercises that can be maintained for a longer period of time. Anaerobic activities are those where normal breathing can be used to supply the oxygen needed to the working muscles.

Exercising has various effects on the body. Some of these effects are immediate and occur within the first few minutes of exercise. The first immediate effect of exercise is an increased heart rate. This is because the working muscles need more oxygenated blood delivered to them, so the heart has to work harder at pumping more blood around the body. The average resting heart rate is between 60-80bpm. During exercise the average is 130bpm. This varies depending on the intensity of the exercise.

Another immediate effect on the body is an increase in depth and frequency of breathing. In order to produce energy, the body requires oxygen. Your breathing quickens to increase the amount of oxygen being taken in by the lungs and is distributed to your working muscles.

As you exercise, your body begins to heat up. This is another immediate effect. You often can tell if someone has been exercising by their face; their skin may be red and they may be sweating. When you overheat, your body releases sweat and blood rushes to the surface of your skin. This allows you to cool down quicker. 

Within a day or two, you will see the short term effects of exercise. A performer may feel tired or fatigued. Your muscles may ache and feel quite heavy. Over exertion (working too hard) can cause dehydration that leads to light-headedness.  It can also cause nausea, a feeling of sickness. Depending on the intensity of the exercise, the performer might experience 'delayed onset of muscle soreness' (DOMS). This is when the lactic acid builds up in the muscles as a result of intense, anaerobic exercise. It causes the muscles to ache for up to 48 hours.

Cramping is another short-term effect of exercise. This is when all the muscles tighten and fail to relax, causing pain. All of these short-term effects are relatively common. They will reduce in frequency and possibly stop altogether once you’ve established a regular exercise routine.

o   The increase of adrenaline, often even before exercise has begun, causes the heart rate to rise. That then increases Cardiac Output, the volume of blood that the heart is able to pump out per minute.

o   Increases in lactic acid, carbon dioxide and temperature all cause further increase to the heart rate.

o   Oxygen levels within the blood decrease which causes increased diffusion at the lungs.

o   Blood pressure increases, therefore increasing flow rate and the speed of delivery of oxygen and nutrients to the working muscles.

o   Vasodilation and vasoconstriction ensure blood is directed to areas that need it (muscles, lungs, heart) and away from inactive organs. 

o   Changes in the concentration of carbon dioxide and oxygen in the blood are detected by the respiratory centre which increases the rate of breathing.

o   The intercostal muscles help the expansion of the thoracic cavity work harder to further increase the expansion during inhalation, to draw in more air.

o   The higher rate of muscle contraction reduces energy stores and so increases a higher rate of energy metabolism.

o   The body’s energy stores are slowly depleted.

o   Myoglobin releases its stored oxygen to use in aerobic exercise. Oxygen can now be diffused into the muscles from the capillaries more quickly due to the increased oxygen concentration in the muscles. 

In order to make physical changes to the body, exercise must be built into a daily routine. Developing fitness takes a long time and it can take months or even years to see the long-term effects of exercise on the body. The first noticeable change you may see following long-term exercise is a change in body shape. You may become more muscular, lose weight or become more toned. Specific changes will depend on the training, for example, a weight lifter may develop larger bicep muscles.

Another long-term effects is that there will be an increase in the size of the heart. This is known as hypertrophy. The heart is a muscle and once it starts to be used, it will grow in size like any other muscle. If the heart is bigger and stronger, it is more efficient and it will be able to eject more blood with each contraction. This means it can beat less for the same volume of blood to the working muscles.

Another long-term effects is a reduced resting heart rate, otherwise known as bradycardia. Performers may find their resting heart rate drops to around 50bpm or even lower if they’re extremely fit. This means their stamina will increase as their cardiovascular endurance has been improved. They will be able to exercise longer at a faster pace.

Muscular endurance will increase, meaning that a muscle can be worked for longer. Muscular strength will also increase. Speed is also improved with exercise. This is helpful for a range of sports, such as basketball. Suppleness can also be acquired through long-term exercise. This enables greater ranges of movement around a joint. 

o   The cardiac muscle surrounding the heart increases in size, resulting in thicker, stronger walls and therefore increases in heart volumes. The more blood pumped around the body per minute, the faster oxygen is delivered to the working muscles.

o   The number of red blood cells increases, improving the body’s ability to transport oxygen to the muscles for aerobic energy production.

o   The density of the capillary beds surrounding the muscles and lungs and heart increases as more branches develop. This makes gaseous exchange more efficient.

o   Arterial walls become more elastic which allows greater tolerance of changes in blood pressure.

o   The amount of lactic acid is much lower during high-intensity activities, due to the circulatory system providing more oxygen and removing waster products faster.

o   The respiratory muscles (intercostal) increase in strength. This results in larger respiratory volumes, which allows more oxygen to be diffused into the blood flow.

o   An increase in the number and diameter of capillaries surrounding the alveoli leads to making gaseous exchange more efficient.

o   Increased number of mitochondria means an increase in the rate of energy production.

o   The muscles, bones and ligaments become stronger to cope with the additional impact put through them.

o   Muscles are capable of storing a larger amount of glycogen for energy.