Effects of Exercise on the Muscular System

Question 1

What are the positive Long term effects of exercise on the body?

Answer 1

• Increased thickness of each muscle fibre (hypertrophy) which improves strength and contractile speed.
• Increases number of muscle fibres (fibre hyperplasia), increased strength of contraction and potentially increased neuron size = stronger contraction
• Increased availability of the fuel source required - increased metabolism of triglycerides (fats).
• Increase in myoglobin = more oxygen transportation in muscle cells
• Increase in glycogen = readily available source of fuel
• Increased tendon strength = decreased risk of overuse tendon injury
• Increase capillarisation = increased delivery of o2
• Slow oxidative and Fast Oxidative fibres develop bigger and more capillary beds, increasing mitochondrial density = increase production of energy aerobically.

Question 2

What are the long term negative effects of exercise on the muscular system?

Answer 2

• Repeated bouts of physical activity without suitable rest periods can cause overuse injuries in muscles.
• Possible injuries such as fasciitis (inflammation of the sheath around a muscle) can occur, particularly in the tibialis anterior muscle.
• Tendonitis - inflammation of the muscle tendon from overuse.

Question 3

What are the short term positive effects of exercise on the muscular system?

Answer 3

• Increased blood flow to your muscles (changes from 5% of available blood in muscles at rest to 80% during exercise). This increases oxygen and energy available to your muscles.
• Energy during muscle contraction is lost as heat, our muscle temperature rising by 1-2°, enables muscles to become more flexible and apply greater forces over a longer joint range = reduced risk of injury

Question 4

What are the short term negative effects of exercise on the muscular system?

Answer 4

• Increased chance of muscle soreness (however, repeated bouts of activity reduce this effect).
• High intensity exercise can cause fatigue and affect other sessions if not appropriately moderated.
• Energy stores and myoglobin levels within the muscle can become depleted.
• Lactic Acid Build up

Question 5

What are the positives of a warm up?

Answer 5

• Increased Flexibility and range of movement (at joint)
• Increased speed of delivery of oxygen to muscles
• Increased muscle temperature
• Increased elasticity/extensibility of muscle tissue so can stretch further
• Increased speed/force of contraction or muscles work faster
• Increased speed of nerve impulses
• Increased enzyme activity
• Reduced muscle soreness/DOMS/Lactic Acid build up

Question 6

Why is a cooldown needed?

Answer 6

• Keeps capillaries dilated maintains blood flow to the muscles after physical activity
• provides an opportunity to replenish glycogen and creatine phosphate
• Refreshes level of oxygen stored in myoglobin and more o2 to muscles
• Refreshes level of oxygen stored in myoglobin and more o2 to muscles
• Prevents blood pooling in muscles
• Increased flexibility and elasticity
• Reduces muscle soreness