Short Answer Questions Flashcards
Describe 3 characteristics that are different between Type I, IIA, & IIX muscle fibers.
Mitochondrial volume/density is highest in type I, then type II, & then IIX. Capillary density is highest in type I, then type IIA, & lastly IIX. Contractile speed is fastest in type IIX, then type IIA, then type I.
Name 3 Track & Field sports in which ATP-PCr energy system is predominant.
High jump, shot put, javelin
Name 3 sports in which the Lactic Acid energy system predominates.
400m dash, wrestling, MMA
Name 3 sports in which the Aerobic system predominates.
Running any distance over 1500m
Describe the role of satellite cells in skeletal muscle.
Repair damaged skeletal muscle, promotion of hypertrophy & hyperplasia
According to the work of Macnaughton et al., describe the response of muscle protein synthesis following a 40 vs 20 gram bolus of ingested whey protein.
40g whey promotes greater muscle protein synthesis following whole body resistance training in young trained men than 20g of whey
According to the work of Antonion et al., what changes are seen with a high protein diet combined with a periodized resistance training program?
Increase in LBM, decrease in fat mass. Lower protein group saw no changes in fat mass.
What is the difference between protein spread theory & protein change theory?
Protein spread theory: there must be sufficient change in protein intake (g/kg/d) between groups to see a difference in LBM &/or strength. Protein change theory: there must be a sufficient change from baseline in protein intake to see changes in LBM &/or strength.
According to Moore et. al., what are the differences in myofibrillar protein synthesis in older vs younger individuals after consuming protein.
Older individuals are less sensitive to protein intake vis a vis MPS than younger
What amino acid is most important to determining protein quality?
Leucine
List the essential amino acids
PVT TIM HALL: Phenylalanine, valine, threonine, tryptophan, isoleucine, methionine, histidine, arginine (conditionally essential), lysine, & leucine
Describe the classic method of carbohydrate loading
Deplete skeletal muscle glycogen over a 3 day period via carbohydrate restriction & exhaustive exercise. Then perform 3 days of exhaustive exercise with a high carbohydrate diet
Describe the acute effects of carbohydrate supplementation on intermittent sports performance.
Intake pre & during a game/race will improve performance generally
Give a brief summary of the effects of oral carbohydrate rinsing & its effects on performance.
Carb. mouth rinses may improve performance by 2-3% during exercise lasting one hour in duration, when compared to a placebo.
Summarize briefly the amount of carbohydrate needed to enhance endurance exercise capacity.
Classic advice says to consume 30-60g/hr. Newer work shows that oxidation rates can reach higher values when multiple transportable carbohydrates are consumed (up to 105g/hr0, (ex. glucose:fructose)
Describe a myth about carbohydrate feeding pre-exercise,
That you shouldn’t consume carbohydrate in the hour pre-exercise due to rebound hypoglycemia. Symptoms of hypoglycemia may occur, but they do not seem to affect performance.
According to the work of Randell et al., describe the range of maximal fat oxidation in athletes, any sex differences, & differences in sports.
Mean MFO=.59 g/min, MFO is higher in females when expressed per unit FFM (11 vs 10 mg/kg/min). Soccer players were highest in this group (10.8 mg/kg/min), American football players were lowest (9.2 mg/kg/min).
Explain the differences in fat oxidation between rowing & cycling across a range of exercise intensities.
Higher in rowing across a range of intensities matched for energy expenditure. Possible due to larger muscles being recruited in rowing.
Explain briefly the effects of omega-3 fatty acid supplementation for 12 weeks on a group of healthy older females.
Resulted in lower triglycerides, increased energy expenditure during exercise, & increased LBM.
What does the scientific literature indicate regarding the effects of CLA supplementation on measures of body composition?
Inconsistent with regards to weight loss, possible adverse effects on glucose metabolism & lipid profile
Describe the body composition alterations that occur in a fed vs fasted state after aerobic exercise training.,
There is no difference
Describe the typical loading protocol for creatine.
20g/d for 1 week (in divided doses)
Which amino acids make up creatine?
methionine, arginine, & glycine
How does creatine supplementation affect meat eaters vs vegetarians vis a vis brain function.
Creatine has a more profound affect on vegetarians with regards to memory
Describe the effect of creatine supplementation on post exercise skeletal muscle glycogen storage.
Can augment skeletal muscle glycogen storage when combined with carbohydrate
List 7 track & field events that would benefit from creatine supplementation.
discus, shot put, javelin, pole vault, high jump, long jump, hammer
Describe the effects of creatine monohydrate vs creatine ethyl ester.
Creatine ethyl ester is not as effective at increasing serum & muscle creatine levels, or in improving body composition, muscle mass, strength, nor power
Describe the effects of creatine monohydrate on myosin heavy chain expression.
Increases type 1, type 11A, & type IIX myosin heavy chain mRNA expression, & MHC protein
Is there a benefit for creatine supplementation vis a vis muscle disorders?
Yes- on muscular dystrophy & idiopathic inflammatory myopathies
Is there a timing effect (pre vs post exercise) regarding creatine supplementation in healthy older adults?
Similar in older adults with regards to muscle mass changes.
What is the genotype that will most likely benefit the most from caffeine supplementation?
Those that are homozygous for the A allele of the polymorphism CYP1A2 gene respond best.
Describe the dose response of an energy drink containing caffeine on muscle performance.
1mg/kg had no effect, while 3mg/kg improved half-squat & bench press maximal power.
Describe the effects of combining caffeine with p-synephrine on resistance exercise performance.
Supplementation of 100 mg of p-synephrine alone & with 100mg of caffeine significantly augmented resistance exercise performance.
List 5 sports in which caffeine may exert an ergogenic effect.
Distance running, rowing, rugby, powerlifting, soccer
Describe briefly the difference in caffeine-habituated vs. caffeine-naïve individuals with regards to the ergogenic effect of the drug.
Caffeine-habituated will respond better.
List some of the possible mechanisms by which caffeine exerts an ergogenic effect.
Increased CNS alertness, enhanced lipolysis, increased pain threshold, enhanced thermic effect
What is the recommended dosage of caffeine needed to exert an ergogenic effect?
3-6mg/kg
What are some possible side effects from too much caffeine?
headaches, dizziness, restlessness, anxiety, insomina
Discuss the differences between coffee & caffeine in terms of their ergogenic effect.
They can both enhance performance, caffeine in supplemental form having a higher intensity.
Provide a brief list of sports/activities in which consuming protein + carbohydrate during the peri-workout window may be beneficial.
2-a day workouts, 90min+ endurance exercise, high intensity resistance training, competition lasting several days
Describe which nutrient timing strategy was superior (Pulse, Intermediate, or Bolus) in the paper by Areta elt al.
Four feedings of 20g of whey protein every 3 hours (intermediate) was better than Pulse feeding (8 feedings of 10g of whey every 1.5hrs) & Bolus feeding (2 feedings of 40g every 6 hrs), in terms of MPS stimulation
In the paper by Kanda et al., describe the differences between casein, whey, & soy vis a vis MPS & the initial peak in plasma amino acids.
Whey was fastest, followed by milk proteins, & lastly casein. Milk proteins are more effective than soy vis a vis protein synthesis.
List some of the benefits of post workout supplementation found in US Marine Recruits.
Compared to the placebo & control groups, the protein-supplemented group saw an average of 33% fewer total medical visits, 28% fewer visits due to bacterial/viral infections, 37% fewer visits due to muscle/joint problems, & 83% fewer visits due to heat exhaustion.
Discuss briefly if consuming a high or low protein diet for 2 months modifies the thermic response to a standard meal.
There is no metabolic adaptation to consuming a high protein diet.
Discuss briefly how meal timing/pattern impacts TEF.
There is a reduced TEF with an irregular (vs regular)
Describe briefly what happens regarding an isocaloric low-carbohydrate ketogenic diet vs a high carbohydrate diet on changes in body composition.
An isocaloric ketogenic diet did not confer a increased reduction in body fat.
What are the differences in dietary protein requirements between young & old individuals?
Older individuals are less sensitive to low protein intakes & require more relative protein intake in a single meal to maximally stimulate postprandial rates of MPS.
Describe the effects of breakfasts higher in protein on appetite, energy expenditure, & fat oxidation.
Increases postprandial energy expenditure, & fat oxidation, reduces hunger, & increases satiety when compared to a carbohydrate-based breakfast
Regarding the most often used measures of body composition in sports science labs (underwater weighing, DEXA, Bod Pod), which are two-vs-three compartment models?
2-compartment (fat & lean body mass): underwater weighing & Bod Pod
3-compartment (fat, bone, bone-free lean tissue mass): DEXA
Describe the basic theory behind beet root juice.
May increase nitric oxide availability, which may improve performance by lowering the oxygen cost of exercise.
Describe the role of whole grain intake regarding mortality, CVD, CHD, stroke, & diabetes based on observational study.
Observational study suggests an inverse relationship between whole grain consumption & risk of mortality from CVD, CHD.
Describe the role of fish oil + aerobic exercise on CVD risk factors & body composition.
Reduction in body fat levels & CVD risk
Describe briefly the effect of coffee consumption on overall & cause-specific mortality.
Lowers the risk of heart disease, diabetes, chronic respiratory diseases..