HSE304 Lecture Notes - Lecture 3: Glycolysis, Phosphofructokinase, Phosphorylase
Topic 3: Physiological bases for performance and training in sprint sports 1
Limitations to high intensity exercise
- DFN: Exercise intensity greater than 100% VO2max, rapid onset
of fatigue
- Capable of performing 250-300% above VO2max
- Peak power: highest power in the test, early on
- End power: power at end of test
- Mean power output: average power over test
- Fatigue index: % fall in PPO to EPO
Determinants of sprint
- Psychological domain: motivation/arousal
- Biomechanics: skill/technique
- Physiological mechanisms: muscular power, fibre type/distribution/recruitmentfatigue
resistance, CrP glycolysis & aerobic metabolism, muscle mass, gender, training, genetic
potential, enviro
- Sprint athletes: heavier/taller than endurance
→ Muscle mass & Fibre composition
- Muscle mass: larger mass = more powerful
- Power = muscular force x shortening velocity
- Fibre type composition: FT more powerful & more fatigable
- FT fibre area: larger = more powerful, < shortening velocity
- Power – weight ratio
- Anaerobic performance increases with age during growth
- Maximal performance reached in twenties
- Decline is linear with age ~ 6%/decade
- Decline is similar in males/females
→ Genetics and sprint potential
- Monocarboxylate (lactate/pyruvate) transporter 1 gene (MCT1) A1470T
polymorphism. The MCTI TT genotype is positively associated with elite sprint/power
atehletic status
- A-actinin 3 deficiency (ACTN3 577XX) is under-represented in sprint/power athletes
→ Substrate availability
- Initial short duration sprints rely predominantly on glycolysis and CrP degradation
- As increase duration of sprint exercise, increase contribution from glycolysis
- Reduction in creatine phosphate over time as sprint continues as less CP left in fibres,
depleted and no more fuel developed of CP
- After 30s sprint high rely on aerobic sources
Document Summary
Topic 3: physiological bases for performance and training in sprint sports 1. Dfn: exercise intensity greater than 100% vo2max, rapid onset of fatigue. Peak power: highest power in the test, early on. End power: power at end of test. Mean power output: average power over test. Fatigue index: % fall in ppo to epo. Physiological mechanisms: muscular power, fibre type/distribution/recruitmentfatigue resistance, crp glycolysis & aerobic metabolism, muscle mass, gender, training, genetic potential, enviro. Muscle mass: larger mass = more powerful. Power = muscular force x shortening velocity. Fibre type composition: ft more powerful & more fatigable. Ft fibre area: larger = more powerful, < shortening velocity. Anaerobic performance increases with age during growth. Decline is linear with age ~ 6%/decade. Monocarboxylate (lactate/pyruvate) transporter 1 gene (mct1) a1470t polymorphism. The mcti tt genotype is positively associated with elite sprint/power atehletic status. A-actinin 3 deficiency (actn3 577xx) is under-represented in sprint/power athletes.
