HIIT Flashcards
Describe HIIT
High-Intensity Interval Training
- Near maximal effort
- Elicits 80% max HR
- Rest Periods
Define MICT
Moderate Intensity Continuous Training:
- Exercise performed continuous manner
- Lower intensity than HIIT
Describe SIT
Sprint Interval Training
- VO2max Intensity
- All-out effort
- REst periods
Which skeletal muscle adaptations occur from interval training?
- Mitochondrial response: enzyme levels; electron transport chain complexes
- Changes each fiber type
- Muscle capillary density
What regulates substrate metabolism during submaximal exercise?
- skeletal muscle mitochondrial density
What does an increase in mitochondrial content promote?
- Increase reliance on fat oxidation
- Proportional decrease in carb oxidation
Which techniques are used for investigating the effects of exercise on skeletal muscle mitochondria?
- Changes in signaling proteins
- Gene Expression
- Mitochondrial protein synthesis rate
- Enzyme content
- Volume of mitochondria (microscope)
- Oxidative Phosphorylation Capacity
How quickly can Citrate Synthase Activity increase after HIIT or SIT sessions?
- 24hr after 1 session
How much does Citrate Synthase and Cytochrome C Oxidase increase by following 6-7 sessions of HIIT or SIT?
- 25-35%
What happens when exercise duration and intensity are held constant regarding mitochondrial content?
- Plateau after 5 days of training
What happens to mitochondrial content when intensity continues to increase progressively?
- Rises for at least several weeks
What does evidence suggest about exercise intensity?
Cellular stress occurs in proportion to exercise intensity:
- Greater metabolic response to high-intensity exercise compared to moderate
Explain the study that shows superior mitochondrial adaptation from interval compared to continuous
- Counterweighted, single-leg cycling
- study adaptations in same subject
- 10 young men
- 6 sessions HIIT 1 leg
- 6 session MICT other leg
- Matched total work
- 2 weeks
Describe the differences between MICT and HIIT when matched for work
- Skeletal muscle capillarization greater in MICT
- Skeletal mitochondrial density greater for HIIT
- VO2max greater for HIIT
What can exercise training do for individuals with type 2 diabetes? What is not known about it?
- Improve glycaemic control
- Unknown optimal training regimen
What is the acute response of the pancreas to exercise bouts?
- Decrease Insulin Secretion
- Increase Glucagon Secretion
What is the acute response of the liver to exercise bouts?
- Increase in Glucose Release
What is the acute response of adipose tissue to exercise bouts?
- Increase in Triacylglycerol Breakdown
- Increase in NEFA Release
How does HIT compare to MICT with glycaemic improvement?
HIT
- Confer superior glycaemic improvement with lower time commitment
How do athletes achieve training in a low carbohydrate state?
- Fast overnight: reduce glycogen content/lowers carb available
- Training 2/day: depletes muscle glycogen from first bout
- Sleep Low: both above; reduced muscle glycogen by training, reduced liver glycogen by fasting
Why would someone train in low carb availability?
Type 2 Diabetes
- Superior Glycaemic improvements
- High-intensity after meal
- low-intensity fasted conditions
what are the benefits of strength training for glycemic control?
- promotes skeletal muscle hypertrophy and increases strength,
- more powerful contractions fuelled by glycolysis and supported by higher lactate dehydrogenase content
what are the benefits of aerobic training for glycemic control?
- enhances cardiovascular function
- promotes skeletal muscle mitochondrial biogenesis
- improving exercise endurance
