Transcript BTEC National Sport

BTEC National Sport
Key Learning Points
for Unit 2
© Hodder Education 2010
BTEC National Sport
The Physiology of Fitness
Exercise & the Body Systems 1
• At the onset of exercise, the various systems respond to try
to increase oxygen delivery, energy production and carbon
dioxide removal.
© Hodder Education 2010
BTEC National Sport
The Physiology of Fitness
Exercise & the Body Systems 2
• The short-term effects of exercise on the body systems are
as follows:
– Musculoskeletal system: increased joint range of movement; micro-tears in
muscle fibres from resistance exercises
– Energy system: ATP is produced by anaerobic energy systems – the
phosphocreatine energy system, the lactic acid energy system and the
aerobic energy system
– Cardiovascular system: increase in heart rate; increase in blood pressure;
redirection of blood flow to working skeletal muscles and skin surface
– Respiratory system: increase in breathing rate; increase in tidal volume.
© Hodder Education 2010
BTEC National Sport
The Physiology of Fitness
Energy System Adaptations to Aerobic Exercise
• Adaptations to aerobic exercise are:
– Cardiovascular system: cardiac hypertrophy; increased stroke volume;
decreased resting heart rate; increased number of capillaries; increased number
of red blood cells; decreased haematocrit.
– Respiratory system: decreased resting breathing rate; increased lung volume;
increased vital capacity; increased tidal volume (in maximal exercise); increased
strength of respiratory muscles; increased capillarisation around alveoli.
– Neuromuscular system: increased myoglobin content; increased number of
capillaries; increased number of mitochondria; hypertrophy of slow-twitch
muscle fibres; increased stores of glycogen; increased stores of fat.
– Energy systems: increased number of aerobic enzymes; increased breakdown
of fat.
© Hodder Education 2010
BTEC National Sport
The Physiology of Fitness
Energy System Adaptations to Anaerobic Exercise
• Adaptations to anaerobic exercise are:
– Cardiovascular system: no significant adaptations.
– Respiratory system: no significant adaptations.
– Neuromuscular: hypertrophy of fast-twitch muscle fibres; increased content
of ATP; increased content of PC; increased tolerance to lactic acid.
– Energy systems: increased number of anaerobic enzymes.
– Skeletal system: increased strength of bones; increased strength of
tendons; increased stretch of ligaments.
© Hodder Education 2010
BTEC National Sport
The Physiology of Fitness
Reviewing the Effects of Exercise on the Body Systems
• Methods of investigation include comparison of pre-exercise,
during-exercise and post-exercise physiological readings.
• Physiological readings include heart rate, blood pressure,
flexibility tests, tidal volume rating of perceived exertion.
• Both acute and long-term adaptations to the body systems
need to be examined.
© Hodder Education 2010