Exam Questions Flashcards
What are the five stages, termed kinases, in the insulin stimulated translocation of GLUT-4 for glucose disposal?
- Insulin receptor triggers → phosphorylation of downstream kinases
- IRS-1
- Pi3K
- Akt - Central regulator of cellular processes responsible for anabolism → Activated by Pi3K
- AS160 phosphorylates → activate RAB = GLUT-4 vesicles releasing GLUT-4 proteins
Why do People with Obesity free IMTG at a lower rate? (4 points*)
Insulin resistance = ↑ adipose tissue release
↑ lipoprotein lipase activity and FFA availability
Direct IMTG inhibition
Exacerbated by IMTG ↓ turnover
FFA entry to energy stores
Name the three main energy systems involved in ATP production during maximal team sport exercise (e.g. repeated sprint exercise), and identify the changing contribution of one system from the 1st to the 10th sprint (4 points*)
- ATP PCr
- Anaerobic Glycolysis
- Aerobic Glycolysis
ATP PCr is the main system used in maximal sprints for 5-6 seconds
↓
Responsible for 50% of ATP production.
↓
Contribution largely determined by extent in which they are replenished during recovery.
↓
PCr recovery kinetics are extremely complex, reflected by large individual and between protocol differences
Define and outline 4 health implications of low energy availability
↓ Bone health → Lack of energy intake/calcium intake = brittle/low-density bone complexity & reduced estrogenic (Result in osteoporosis)
Haematological defects → Deficiency in iron = anaemia, low blood pressure, change in stool colour, heart palpitations etc
Cardiovascular effects → Low blood pressure and bradycardia
↓ Growth and development = ↓ insulin and growth hormone
What are four potential nutritional problems facing the travelling international athlete?
- Stress
- Avoiding dehydration
- Weight management
- Immune suppression
Outline the four key components of a fad diet
- Promote quick weight loss
- Recommend expensive supplements
- Claim to impact appetite
- Claims to work for everyone
State two proposed mechanisms and explain the effects of beetroot juice on submaximal exercise metabolism and exercise performance (3 points*)
Contractile efficiency
Mitochondrial efficiency
Nitrate ↑ efficiency of muscle contractions → less ATP hydrolysis for contractions = ↓ rate of fatigue
Reductions in PCr = continued production of ATP + ↓ time to fatigue.
Mitochondrial efficiency ↑ with nitrate intake = ↑ ATP from the same amount of oxygen
List 3 of the most popular fad diets and evaluate one of them in relation to its effectiveness as a weight loss strategy (provide a for and against)
Dunkan deit
Paleo deit
5: 2 diet
- Consists of a normal diet for 5 days and a fast for 2 days. Claims to improve life span, brain function and protect against dementia and Alzheimer’s.
- Pros- Only requires 2 diet days allowing potential for greater success in weight loss and perseverance
- Cons- Diet days result in skipping meals which can result in dizziness, headaches, difficulty concentrating and making you irritable
Describe the proposed link between the gut microbiota activity and development of insulin resistance with a fat/energy rich diet (3 points*)
Fat/energy rich = cause common organisms in human gut balance to change result in ↑ LPS production after digestion
LPS protein binding occurs → surge of immune responses = pro-inflammatory enzymes
Enzymes migrate into the cell and interfere with the insulin signalling surge = insulin resistance
How does obesity induce low-grade adipose tissue inflammation and promote insulin resistance? (4 points*)
Obesity = hypertrophic (Large) adipocytes release pro-inflammatory cytokines
MCP-1 attracts M1 macrophages also releasing pro-inflammatory cytokines
⟲ of low-grade chronic inflammation occurs
Cytokines signaling pathways ↑
Insulin receptor pathways ↓ = insulin resistance
State and describe the 4 R’s associated with innate immunity
Recognition → Receptors recognising damaged cells, once detected cytokines released
Recruitment → Cytokines release protein molecules which recruit leukocytes from blood-stream
Removal → Neutrophils and Macrophages remove pathogens by engulfing damaged cells
Repair → Cytokine release initiates tissue repair cells
List four nutritional strategies which are suggested to reduce inflammation
- Mediterranean diet
- Vitamin D
- Omega 3
- Anthocyanins
Explain the difference between pro and pre-biotics
Pre-biotics
↓
Gut cannot digest
Encourages beneficial gut microbes
Maintains suitable levels of inflammation
Intestinal peptide secretion, increasing satiety
Pro-biotics
↓
Capable gut bacteria administered orally
Lactobilicus ↑ lipoprotein lipase inhibitor FIAF
Define Sarcopenia
Sarcopenia ↑ progressive and generalized loss of skeletal muscle mass and strength with age
EWGSOP recommend the use of low muscle mass and low muscle function for the diagnosis of sarcopenia
Diagnosis requires documentation of low muscle mass PLUS documentations of either low muscle strength or low physical performance
Outline typical sodium bicarbonate supplementation protocols for a rugby match with special reference to timing and dosage. Briefly describe the advantages and disadvantages of each supplementation protocol and justify their potential use before a rugby match
Dose of 0.2-0.4g/kg of body mass
60-150 mins before exercise
or
Split doses over 30-180min period
or
Serial loading: 3-4 smaller doses per day for 2-4 consecutive days before event
Advantages?
Disadvantages?
