1. Active vs. Passive Recovery Recovery after exercise is associated with reduction of blood lactate concentration Active recovery (low intensity aerobic exercise) reduces recovery time compared to passive recovery During active recovery, blood flow to the active muscles remains high Since the energy consumption during active recovery remains high, the use of lactate as an energy source is higher compared to passive recovery

2. Active vs. Passive Recovery Recovery after exercise is associated with reduction of blood lactate concentration Active recovery (low intensity aerobic exercise) reduces recovery time compared to passive recovery During active recovery, blood flow to the active muscles remains high Since the energy consumption during active recovery remains high, the use of lactate as an energy source is higher compared to passive recovery

3. Economy of Movement and Mechanical Efficiency in Exercise Efficiency- the relation between input and resulting output The quantity of energy required to perform a particular task in relation to the actual work accomplished Economy of physical effort

4. Economy Mechanical / biomechanical efficiencyEnvironmental factors

5. Mechanical Efficiency Actual mechanical work accomplished Mechanical efficiency (%) Input of energy =x 100 = kgm VO 2 x 100 = השקעה תפוקה

6. Mechanical Efficiency Example: - 13,300 kgm of work were generated during 15 minute ride on a stationary bicycle. - Total oxygen consumption 25 liters. Mechanical efficiency calculation: Energy input: 25 liter of oxygen x 5kcal = 125 kcal 1 kcal = 426 kgm 125 x 426 = 53,250 kgm Mechanical efficiency = 13,300 kgm 53,250 kgm X 100= 24.9 %

7. Efficiency of the Human Body The efficiency of human locomotion in walking, running and cycling ranges between 20-30% 20-30% of energy consumption is converted to mechanical work and 70-80% is converted directly to heat During rest 97% of energy consumption is converted directly to heat

8. Muscle Profile

9. Muscle Fiber Types

10. Motor Units Number of muscle fibers Types of muscle fibers

11. Muscle Fiber Types Characteristics of the Three Muscle Fiber Types Fast Twitch B (FT-B(Fast Twitch A (FT-A(Slow Twitch (ST(Fiber Type Very fastFastSlowContraction time Very largeLargeSmallSize of motor neuron LowIntermediateHighResistance to fatigue Short term anaerobicLong term anaerobicAerobicActivity used for Very highHighLowForce production LowIntermediateHigh Mitochondrial density LowIntermediateHighCapillary density LowIntermediateHighOxidative capacity High LowGlycolytic capacity CP, GlycogenGlycogenTriglyceridesMajor storage fuel

12. Distribution of Muscle Fiber Types Genetic association In none active population 40- 50% ST Long distance runners 50-90% ST Short distance runners 30-55% ST Weight lifters 40-60% ST Muscle fiber type has only a moderate effect on maximal performance

13. Can training Change Fiber Type? Training a FT -fibered muscle for endurance will not increase the number of ST fibers, nor will training a ST- fibered muscle for strength and power increase the number of FT fibers. With the proper training, FT -B fibers can take on some of the endurance characteristics of FT -A fibers and FT -A fibers can take on some of the strength and power qualities of FT-B fibers. However, there is no inter- conversion of fibers. FT fibers cannot become ST fibers, or vice versa. What an athlete is born with is what he or she must live with.

14. Economy of Movement and Mechanical Efficiency in Exercise Efficiency- the relation between input and resulting output The quantity of energy required to perform a particular task in relation to the actual work accomplished Economy of physical effort

15. Economy Mechanical / biomechanical efficiencyEnvironmental factors

16. Mechanical Efficiency Actual mechanical work accomplished Mechanical efficiency (%) Input of energy =x 100 = kgm VO 2 x 100 = השקעה תפוקה

17. Mechanical Efficiency Example: - 13,300 kgm of work were generated during 15 minute ride on a stationary bicycle. - Total oxygen consumption 25 liters. Mechanical efficiency calculation: Energy input: 25 liter of oxygen x 5kcal = 125 kcal 1 kcal = 426 kgm 125 x 426 = 53,250 kgm Mechanical efficiency = 13,300 kgm 53,250 kgm X 100= 24.9 %

18. Efficiency of the Human Body The efficiency of human locomotion in walking, running and cycling ranges between 20-30% 20-30% of energy consumption is converted to mechanical work and 70-80% is converted directly to heat During rest 97% of energy consumption is converted directly to heat

19. Muscle Profile

20. Muscle Fiber Types

21. Motor Units Number of muscle fibers Types of muscle fibers

22. Muscle Fiber Types Characteristics of the Three Muscle Fiber Types Fast Twitch B (FT-B(Fast Twitch A (FT-A(Slow Twitch (ST(Fiber Type Very fastFastSlowContraction time Very largeLargeSmallSize of motor neuron LowIntermediateHighResistance to fatigue Short term anaerobicLong term anaerobicAerobicActivity used for Very highHighLowForce production LowIntermediateHigh Mitochondrial density LowIntermediateHighCapillary density LowIntermediateHighOxidative capacity High LowGlycolytic capacity CP, GlycogenGlycogenTriglyceridesMajor storage fuel

23. Distribution of Muscle Fiber Types Genetic association In none active population 40- 50% ST Long distance runners 50-90% ST Short distance runners 30-55% ST Weight lifters 40-60% ST Muscle fiber type has only a moderate effect on maximal performance

24. Can training Change Fiber Type? Training a FT -fibered muscle for endurance will not increase the number of ST fibers, nor will training a ST- fibered muscle for strength and power increase the number of FT fibers. With the proper training, FT -B fibers can take on some of the endurance characteristics of FT -A fibers and FT -A fibers can take on some of the strength and power qualities of FT-B fibers. However, there is no inter- conversion of fibers. FT fibers cannot become ST fibers, or vice versa. What an athlete is born with is what he or she must live with.