Training prescription for Anaerobic Adaptations Flashcards
Where can we find creatine kinase within a skeletal muscle fibre?
Mitochondria
M line of the sarcomere
What is creatine kinase important for?
Resynthesizing phosphocreatine
How else may a sprinter synthesize ATP?
If breakdown of ATP is high, there will be increased levels of ADP.
Adenylane kinase is an enzyme which catalyses the reaction of 2 ADP’s to ATP and AMP.
Why is AMP important?
AMP is important at signalling events within the muscle fibre. Certain key metabolic enzymes are sensitive to small changes to AMP.
What is the role of glycogen phosphorlyase?
Glycogen phosphorylase breaks down glycogen (muscle, liver brain). Activated via several pathways. AMP can activate glycogen phosphorylase. Increasing cellular levels of AMP = high breakdown rate of ATP = activate glycogen phosphorlyase.
B form - inactive state
A form - active state
Activated through epinephrine (hormone)
Activated through calcium, calcium released through muscle contraction = the more calcium released the more substrate signaled via glycogen phosphorylase.
AMP and Calcium are the main two, Epinephrine amplifies the response.
What is the role of Phosphofructokinase?
PFK is the rate limiting enzyme in glycolysis.
PFK is activated through AMP, it binds directly to PFK.
Why is there a reduction between sprint 1 and sprint 10 in terms of power output?
Glycogenolytic rate reduced by 91% - rate of breakdown of glycogen - suggesting impaired enzyme activity of glycogen phosphorylase
Glycolytic rate reduced by 87% - rate of glycolysis
Glycogen degradation reduced by 53% - measures from the glycogen molecule all the way down to lactate
Reduced PCr
Increase H+
Impaired enzyme function
Why does the contribution of energy systems differ in sprint 10 compared with sprint 1?
The the contribution of glycolysis lower on sprint 10
Impaired function of glycogen phosphorylase. and PFK.
Glucose-6-phosphate accumulation inhibits the glycogen phosphorlyase.
If glycogen levels are lower, glycolysis system won’t be able to operate to a high rate.
Why would having more mitochondria change the rate at which you can resytnthesize Pcr?
The more mitochondria you gave, the more ATP is available and therefore you can resynthesize PCr.
What are the affects of repeated sprint training on glycogen phosphorylase activity?
Glycogen phophorylase activity did not change significantly
PFK enzyme activity significantly increased. = slightly lower accumulation of G-6-P as glycolysis is working quicker. = Ability to generate ATP anaerobically at a quicker rate
Hexokinase enzyme activity significantly increased
Training Prescription for Anaerobic Adaptation conclusions
- Contribution of PCr, glycogenolysis and gloycolytic rate to ATP production are high in short (6s) sprints.
- Contribution of glycolysis decreases with increasing number of sprints
- Aerobic system contributes ~60% to energy production after 3 repeated 30s maximal efforts
- Repeated sprint interval training increases several markers of glycolytic metabolism.
Adaptations to long term sprint training?
Increase in PFK and hexokinase
No change in glycogen phosphorylase and lactate dehydrogenase
Peripheral adaptations - increased buffering capacity
In terms of dry weight. What is the breakdown of a muscle?
AT REST
24% - ATP 3% - ADP 0.1% - AMP 76.5% - PCr 43.5% - Cr AT REST
What physiological impacts does a 6 second sprint have?
Reduced glycogen concentration 14% Reduced ATP concentration 15% ADP concentration remained the same AMP no change - measures not sensitive PCr dropped significantly 50% reduction
