Practice Quizzes Flashcards
Glucose regulation during moderate intensity exercise is maintained through primarily…
a decrease in insulin and an increase in epinephrine and norepinephine
What is the usual advice for CHO intake postexercise to optimise muscle glycogen resynthesis?
Immediately post exercise (0-4 hrs) consume 1.0-1.2 g of CHO / kg / hr
Oxidative metabolism predominates in the presence of…?
adequate oxygen
The primary role of CHO in the days prior to competitions is to replenish the liver glycogen stores completely (t/f)?
False
Which of the following may occur after ingesting CHO 45 minutes before exercise?
rebound hypoglycemia
ATP has a greater capacity to release energy (or contains more free energy) than creatine phosphate (PCr) (T/F)?
False
CHO have an energy content of around ….?
4.2 kcals/gram
The lower the insulin concentration observed during moderate intensity exercise is a result of what?
Increased catecholamines (epinephrine and norepinephrine) levels
When glucose enters the cell it is immediately phosphorylated by….?
hexokinase
Approx what % of adult body is water (by weight)?
60-70%
Whereabouts does glycolysis occur within the cell?
Cytosol
The rate of muscle glycogen resynthesis post exercise is highest….?
2 hours post exercise
Aerobic resynthesis of ATP occurs in the….
mitochondria in a process called oxidative phosphorylation
What is the metabolic rationale consuming CHO within 4 hours of completing a strenuous, endurance-based session?
GLUT-4 receptors remain at the cell membrane for approx 4 hours post exercise and allow for more glucose to be taken up and stored as muscle glycogen
Do vitamins provide energy?
No
In general, the higher the intensity of exercise, the greater the proportional contribution of…..
anaerobic energy production is
Post exercise ingestion of glucose-fructose (sucrose) results in….
Similar muscle glycogen synthesis and greater liver glycogen synthesis compared to isocaloric glucose ingestion
The energy released from the breakdown of high-energy phosphates, ATP and phosphocreatine, can sustain maximal exertion exercise for about…?
5-10 seconds
Muscle protein synthesis increases after resistance training (T/F)?
True
Ketone body production will increase if…?
CHO intake is restricted to less than 20g/day
Removal of the AA group from an AA to form ammonia is a process called?
Deamination
Following lipolysis, what happens to the glycerol freed from triglycerides?
Travels directly to the liver where it acts as a gluconeogenic substrate
Leucine is the essential AA known to rapidly stimulate muscle protein synthesis (T/F)?
True
The capacity of the aerobically trained muscle to use fatty acids as fuel results in…..?
reduction in lactate formation
sparing of muscle glycogen
sparing of blood glucose
(all of the above)
Muscle mass may be gained during resistance training only when protein intake exceeds 2.0g/day (T/F)?
False, can still see progress
Hormone sensitive lipase (HSL) activity is regulated by….?
epinephrine and insulin
What factors stimulate lipolysis?
AMP and leptin
Muscle protein synthesis will be maximised during conditions of…?
exercise + amino acids
Contemporary recommendations suggest strength athletes require >3.0 grams / kg / BW of protein to increase muscle protein synthesis (T/F)?
False (recommendations is 1.6-1.7g/kg/day)
What is a known risk of sodium bicarbonate loading?
GI disturbances
Examples of phytonutrients are carotenoids found in carrots, broccoli, leafy greens and yellow veges, spinach and polyphenols found in berries, fruits, and wine
True
The dual-energy x-ray absorptiometry (DEXA) can be used to….?
estimate bone density as well as body composition (FM and FFM)
What component contributes the most to total body mass (protein, fat, CHO, minerals)?
Protein
Current densitometry calculations assume fat tissue to have density of…?
0.9 g/cubic cm
What is the clinical standard for measuring bone density?
Dual-energy x-ray absorptiometry (DEXA)
Both hydrostatic weighing and air displacement plethysmography (bodpod) use the principle of densitometry. Density =
mass / volume
Is there strict regulation regarding testing, advertising and promotion of nutritional supplements?
No
During blood buffering, H+ ions combine with bicarbonate to form water (T/F)?
FALSE
Creatine supplementation enhances both performance of high intensity exercise and recovery bouts (T/F)?
TRUE
Which of the following is NOT considered a macronutrient?
- sulfur
- Ca
- magnesium
- iron
iron
What % of creatine in the body is stored within phosphocreatine (PCr)?
67%
Which of the following it NOT a known factor in increasing the likelihood of vitamin D deficiency?
Excess sodium intake (dark skin DOES affect it)
In general, the greatest difference between men and women in terms of % body fat most likely comes from…?
essential fat
Which vitamin is the precursor of Coenzyme A, an essential compound in CHO and fat oxidation?
Vitamin B5 (pantothenic acid)
Creatine is a non essential or essential AA?
non essential (can be synthesised)
What minimum level of hydration % has been shown to impair performance?
1-2%
Potential negative effects of rapid weight loss through fasting or crash dieting include:
- glycogen depletion
- substantial loss of body water
- reduction in body proteins stores
Which of the following is NOT an important factor in the conversion of Pyruvate to Acetyl CoA within the preparatory phase of aerobic glycolysis:
- Thiamine
- Lactate dehydrogenase
- Coenzyme A
- Pyruvate dehydrogenate complex
- Lactate dehydrogenase
not important
Ingredients on food labels are listed from most to least nutritious (T/F)?
FALSE
Which hormone is responsible for monitoring fat storage?
leptin
Which if the following is NOT a process involved in the secretion of renin?:
- Direct release through granular cells within the nephron
- indirect release through macula densa activation
- increased SNS activation
- upregulation of NaCl reabsorption within eccrine sweat glands
upregulation of NaCl reabsorption within eccrine sweat glands
Hyponatreima is…?
low plasma sodium concentrations
REE closely correlates with FFM (T/F)?
True
What water compartment contains the most fluid?
intracellular
Which hormone is responsible for sodium retention ?
aldosterone (NOT sodium retention hormone (SRH))
Sweat rates during strenuous exercise in the heat can be up to….
2-3L/hr
De novo lipogenesis refers to….
the biochemical process of synthesising glucose from non-CHO carbon substrates
Thyroid hormone regulates the gene expression important proteins that influence resting metabolic rate?
Na+/K+ ATPases
Substantial changes in skeletal muscle mass should be reflected in changes in resting metabolic rates (T/F)?
True
The suppression of both appetite and post exercise energy intake depends on which of the following combinations?
Intensity of exercise >70% VO2max; duration of exercise longer than 60 mins
RQ =
VCo2/VO2
Female athletes suffering from bulemia nervosa regularly present with very low body weight (T/F)?
False
Anti-diuretic hormone (ADH) acts on principal cells in the collecting duct of nephrons to initiate the synthesis of what proteins that increase water reabsorption?
Aquaporins
The rate of muscle glycogen synthesis after endurance exercise is influenced by(3):
- amount CHO consumed
- timing CHO intake
- type CHO eaten
Ingestion of 90grams / hr of multiple transportable CHO during prolonged exercise can result in…
- higher exogenous CHO oxidation rates
- better performance
The lower the insulin concentration observed during moderate intensity exercise is a result of what?
increased catecholamines (epinephrine and norepinephrine)
Glycemic index is…
an indicator of the blood glucose response to the ingestion of a particular food
In general, the higher the intensity of exercise, the greater the proportional contribution of…
anaerobic energy production
A smaller amount of the energy is available to the body from a food item high in fibre than from a food item with identical energy content but low in fibre (T/F)?
False
Intramuscular triacylclycerol (IMTG) oxidation is greatest at approx. …. VO2 max
65%VO2 max
Muscle protein synthesis is optimised at which intensity?
MPS does not depend on intensity
Intramuscular triglycerides (IMTG) are preferentially used as an energy source over muscle glycogen during intense exercise (T/F)?
False
Rates of lipolysis are different between trained and untrained individuals (T/F)?
False
IMTG stores are higher in trained people than untrained counterparts (T/F)
True
Chronic high fat diets improve endurance capacity but not time trial performance in humans (T/F)
True