Responses to exercise

Responses to exercise

1. Responses to Exercise

2. Acute responses to exercise

3. Acute responses Immediate/Short term responses Last only for the duration of the training or exercise session and for a short time afterwards (recovery)

4. Cardiovascular responses Increased Heart Rate (HR) Resting HR is usually around 60-80bpm Increases O2 delivery to working muscles Aids removal waste products Will increase until point of exhaustion Maximum HR (MHR) is the highest heart rate value achieved in an all-out effort to the point of exhaustion

5. Increased Stroke Volume (SV) In untrained individuals at rest 60-80mL per beat During exercise this can increase to 110-130mL Females have smaller SV than males Will increase with exercise intensity but may plateau until exhaustion Cardiovascular responses

6. Cardiovascular responses Increased Cardiac Output (Q) Increases as a result of HR and SV increases Delivers O2 to working muscles During max exercise 20-25L/min up to 35-40L/min in highly trained individuals

7. Increased Blood Pressure (BP) Pressure exerted against arterial walls Systolic BP: pressure during heart contraction Diastolic BP: pressure during heart relaxation Normal resting BP is 120/80 during exercise this might increase to 180 or 200/80 or 90 Cardiovascular responses

8. Cardiovascular responses Redistribution of blood flow More toward working muscles up to 80-90% compared to 15-20% during rest Capillaries and arterioles to the muscles vasodilate Capillaries and arterioles to the organs vasoconstrict

9. Cardiovascular responses Increased Arteriovenous Oxygen Difference (AVO2) Difference in oxygen concentration between arterial blood and venous blood The amount of oxygen extracted by the working muscles Can increase from 5mL/100mL blood at rest to 15-18mL during max exercise

10. Respiratory Responses Increased Respiratory Rate (RR) From 12 per min up to 35-50 per min Increased Tidal Volume From 0.5L per breath to 3-5L per breath Increased Ventilation From 5-6L per min to 130-180L per min

11. Increased Oxygen Uptake (VO2) Rest 0.25L/min to 2-3.5L/min Increases with exercise intensity VO2 MAX is the maximum amount of oxygen transported, taken up and used by the body Takes into consideration per kg body weight Generally lower for females Aerobic training can greatly increase VO2 max Respiratory Responses

12. Oxygen Deficit Oxygen supply does not meet oxygen demand Anaerobic pathways used to supply energy Transition from rest to exercise or an increase in exercise intensity

13. Steady State Oxygen supply equals oxygen demand Aerobic pathways used to supply energy Plateau in HR and ventilation

14. Excess Post-Exercise Oxygen Consumption EPOC Also referred to as oxygen debt Oxygen consumed during recovery period Above resting levels Role is to: Replenish PC stores Removal lactic acid and CO2

15. Muscular Responses Increased motor unit and muscle fibre recruitment Increased blood flow to muscles Increased muscle temperature Increased muscle enzyme activity Increased oxygen supply and use Depleted muscle energy stores

16. Chronic Adaptations to Training

17. Body’s long term responses of the cardiovascular, respiratory and muscular systems Three times per week for at least 6-8 weeks Changes can be evident at rest or exercise (sub-max or max) Adaptations remain until training ceases (reversibility or detraining) Depend on type/method, frequency/duration/intensity of training and individual capacities/genetics Chronic Adaptations

18. Aerobic vs Anaerobic Min 6 weeks but more effective after 12 weeks Changes improve efficiency of O2 delivery to muscles in cardiovascular & respiratory systems Can decrease the risk of lifestyle diseases Aerobic Min 6 weeks Greatest change in muscular system Changes enable greater strength, power & speed Anaerobic

19. Aerobic Cardiovascular Changes Increase left ventricle size & volume Increased capillarisation of heart & skeletal muscle Increased SV Decreased resting HR Decreased HR sub-max exercise Increased HR during recovery Increased Q during max exercise Decreased BP Increased AVO2 Increased blood volume & haemoglobin Decreased blood cholesterol & triglycerides

20. Aerobic Respiratory Changes Increased ventilation max exercise Increased VO2 max Increased LIP

21. Aerobic Muscular Changes Increased oxygen utilisation Increased muscular fuel stores Increased oxidisation of glucose & fat Decreased use anaerobic glycolysis system Adaptation muscle fibre type

22. Anaerobic Changes Skeletal and cardiac muscle hypertrophy Increased ATP & PC stores Increased glycolytic capacity Increased strength & size of connective tissues Increase in number motor units recruited Increase speed of nerve impulse transmission Increase speed of muscle contraction