1. Effects of Exercise on Skeletal Muscle A little Background Information

2. Benefits Improved muscle tone Better posture More efficient heart & lung function Less fatigue Looking & feeling better

3. Changes in Muscle Mass NOT an INCREASE or DECREASE in Muscle Fiber number

4. Atrophy Shrinking in mass Due to prolonged inactivity & disuse

5. Hypertrophy Increase in muscle mass & size Due to exercise & use of the muscle

6. Changes to Muscle Strength TrainingStrength Training –Contracting against resistance –Enhances hypertrophy –This is anaerobic –Increases the number of myofilaments in each muscle fiber –The number of muscle fibers does NOT change

7. Changes to Muscle Endurance trainingEndurance training –Increases the muscle’s ability to sustain exercise over a long period of time & is aerobic –Usually does not result in hypertrophy Increases the number of blood vessels & mitochondria This allows for more efficient delivery of O 2 & glucose and greater production of ATP

8. Exercise and Muscle Tissue

9. What are the 4 physiological effects of exercise? Improved muscle tone Improved Posture Better Heart and Lung function Less Fatigue

10. What is are the psychological effects of exercise? Improved Looks Improved Self Image

11. What happens when a muscle is not used? They Atrophy –Shrink or get smaller

12. Identify a “legitimate” reason for inactivity Disease Injury

13. Identify a “bogus” reason for inactivity Laziness –Couch Potato

14. What happens to muscle mass with repeated exercise? Muscle increases in mass –Hypertrophy

15. What happens physiologically to muscle during strength training? Increased myofilaments which… Increases muscle fibers which… Increases muscle mass which… Increases strength

16. What is the difference between strength training and endurance training? Strength training increases overall skeletal muscle –strength and bulk Endurance training is aerobic –increases muscle endurance

17. What types of muscle contractions are typically associated with strength training? Endurance training? ST = Isometric ET = Isotonic

18. What happens physiologically to muscle tissue with aerobic training? Increases blood vessels which… Increases blood flow which… Increases nutrients / oxygen / waste removal which… Increases efficiency

19. What type of muscle(s) is/are improved with strength training? Skeletal

20. What type of muscle(s) is/are improved with aerobic training? Cardiac, Smooth