exam 4

A high H+ concentration can contribute to fatigue by a) interfering with Ca++ binding to troponin. b) All of these answers are correct. c) inhibiting Ca++ release from the sarcoplasmic reticulum. d) reducing the force generated per cross-bridge.

b

Cross-sectional studies demonstrate that the physiological variable responsible for the large variation in VO2 max across the normal (untrained) population is maximal A) heart rate. B) stroke volume. C) arteriovenous O2 difference. D) systolic blood pressure.

b

Endurance training has been shown to reduce the oxygen deficit in subjects performing a bout of submaximal exercise. This is likely due to A) an increased maximal cardiac output. B) increases in the number of mitochondria and capillaries. C) a decreased resting heart rate. D)a greater anaerobic capacity.

b

Studies suggest that elevating the levels of _____________ in the brain can contribute to "central" fatigue during prolonged endurance events A) norepinephrine B) serotonin (5-hydroxytryptamine) C) epinephrine D) acetylcholine

b

Which of the following training adaptations does NOT occur in skeletal muscles following 4-10 weeks of anaerobic exercise training? A) increased muscle buffer capacity B) increased activities of myokinase and creatine phosphokinase C) increased activities of key glycolytic enzymes D) None of these answers is correct

D

Endurance exercise training results in an increase in mitochondria volume within skeletal muscle fibers. The process of synthesizing mitochondria in cells is called ______.

Mitochondrial biogenesis

In examining the mechanisms for exercise-induced fatigue, the vast majority of the evidence points to the a) periphery (i.e., peripheral fatigue) b) central nervous system c) alpha motor neuron in the spinal cord d) Both central nervous system and the alpha motor neuron in the spinal cord are correct

a

Which of the following are essential factors in the successful completion of an ultra-endurance event? A) having trained the body to markedly shift to fat oxidation to fuel the work performed during the ultra-endurance competition B) All of these are essential C) having a superior VO2 max and high lactate threshold D) avoiding carbohydrate intake during the event

a

Which of the following endurance training adaptations assist in maintaining acid-base balance during exercise? A) increased mitochondrial volume in skeletal muscle B) increased M4 form of LDH C) increased glycolytic capacity D)decreased beta oxidation capacity

a

Which of the following endurance training adaptations does NOT result in lower lactate production in the contracting muscles? a) increased glycogen utilization b) increased mitochondrial uptake of pyruvate c) decreased pyruvate formation d) increased H4 form of LDH

a

Which of the following factors DO NOT contribute to the decline in VO2 observed during 84 days of detraining? A) A decrease in maximal heart rate B)A decrease in the maximal arterial-venous O2 difference C) A decrease in maximal stroke volume D) None of these is correct

a

in theory, concurrent resistance and endurance exercise training can impair muscle protein synthesis following a bout of resistance exercise. The proposed mechanism to explain this inhibition is _____________________________________ .a. AMP kinase activation of TSC2 b. AMP kinase activation of mTOR c. AMP kinase activation of PGC-1α d. p38 activation of TSC2

a

Four-to-ten weeks of anaerobic training (high intensity exercise lasting 10-30 seconds) can increase the peak anaerobic capacity by ______ across individuals.

3-25%

Heritability (i.e., genetics) determines approximately _____% of VO2 max variability in sedentary adults.

50

High responders to endurance exercise training (i.e., individuals that achieve large increases in VO2 max) can achieve up to ______% improvement in VO2 max following a prolonged and intense training program.

50

A single bout of resistance exercise training increases muscle protein synthesis by as much as ______% above resting levels?

50-150

It is estimated that _______% of the differences in muscle mass between individuals can be explained by genetic variation

80

Several hormones have the potential to increase muscle protein synthesis. These include: a. testosterone, insulin-like growth factor-1 (IGF-1), and growth hormone b. testosterone, cortisol, and growth hormone c. insulin-like growth factor-1 (IGF-1), glucocorticoids, and growth hormone d. testosterone, insulin-like growth factor-1 (IGF-1), and parathyroid hormone

A

Which of the following endurance training adaptations does NOT result in lower lactate production in the contracting muscles? A) increased glycogen utilization B) increased H4 form of LDH C) increased mitochondrial uptake of pyruvate D) decreased pyruvate formation

A

training only one limb can result in an increase in strength in the untrained limb

cross education

A single bout of resistance exercise training results in an increase in skeletal muscle protein synthesis. This exercise-induced increase in muscle protein synthesis can occur within _____ following the exercise session. a) seconds b) minutes c) days d) hours

d

Carbohydrate supplementation during exercise is most important in performances lasting a) 30 to 180 seconds. b) less than 10 seconds. c) 3 to 20 minutes. d) longer than 60 minutes.

d

During the first four months of an endurance exercise training program, the initial increase in VO2 max is primarily due to A) neural adaptations. B) increases in stroke volume. C) increases in maximal cardiac output. D)Both increases in stroke volume and increases in maximal cardiac output are correct.

d

The addition of myonuclei to growing muscle fibers ______________. a. appears to be essential for optimal muscle hypertrophy in response to resistance training b. is clearly NOT essential for optimal muscle hypertrophy in response to resistance training c, is likely required to maintain the high level of transcriptional capacity needed to synthesize muscle proteins and allow muscle fibers to grow during resistance training d. Both appears to be essential for optimal muscle hypertrophy in response to resistance training and is likely required to maintain the high level of transcriptional capacity needed to synthesize muscle proteins and allow muscle fibers to grow during resistance training are correct

d

The enhanced capacity of the trained muscle to use fatty acids as a fuel results in A) increased uptake of fatty acids. B) decreased utilization of muscle glycogen. C) sparing of blood glucose. D) all of these answers are correct.

d

The increase in VO2 max that occurs following 16 months of endurance exercise training results from A) an increase in the maximal a-vO2 difference. B) an increase in maximal cardiac output. C) an increase in the maximal heart rate. D) both an increase in the maximal a-vO2 difference and an increase in maximal cardiac output are correct.

d

The phenomenon that previous strength training accelerates the re-acquisition of both muscular strength and hypertrophy is commonly referred to as _________. a. motor learning b. the boomerang effect c. satellite cell phenomenon d. muscle memory

d

The principle of specificity of training refers to the fact that exercise training is specific to A) the muscles involved in the activity. B) the fiber types recruited. C) the principal energy system (i.e., aerobic vs. anaerobic) involved in the activity. D) all of these are correct

d

Which of the following has been shown to interfere with cross-bridge "cycling" during exercise? a) an accumulation of ATP b) a decrease in Pi (inorganic phosphate) c) a decrease in Na+ d) an accumulation of H+

d

Which of the following statements are true about the effect of endurance training or detraining on mitochondria volume in human skeletal muscle? A) Five weeks of endurance training can increase skeletal muscle mitochondrial volume by two times about normal. B) Seven days of detraining can reduce mitochondrial volume by 50% below the trained level. C) After a period of detraining, approximately 4 weeks of retraining is required to regain the lost mitochondrial volume. D) All of these are true.

d

Which of the following statements are true about the effect of endurance training or detraining on mitochondria volume in human skeletal muscle? A) Five weeks of endurance training can increase skeletal muscle mitochondrial volume by two times about normal. B) Seven days of detraining can reduce mitochondrial volume by 50% below the trained level. C) After a period of detraining, approximately 4 weeks of retraining is required to regain the lost mitochondrial volume. D)All of these are true.

d

an inability to maintain power output during repeated contractions.

fatigue

An important physiological factor that may contribute to the inhibition of motor unit activation during resistance training is ____________.

golgi tendon organ

Following an acute bout of endurance exercise training, the increase in mitochondrial biogenesis occurs within _____ following the completion of the exercise session.

hours

an increase in the total number of muscle fibers

hyperplasia

Following an acute bout of endurance exercise training, the rise in the activity of calcinuneurin, calmodulin kinase, and AMP kinases occurs within _____ following the exercise session.

minutes

the magnitude of the efferent neural output from the central nervous system to the motor units and the muscle fibers that they activate

neural drive

Several mechanisms have been proposed to explain why concurrent endurance and resistance (strength) training impedes strength development compared to strength training alone. Which of the following mechanisms have NOT been proposed to explain why concurrent training impedes strength development? Neural factors Overtraining Depressed muscle protein synthesis none of these is correct

none are correct

Aging is associated with a decline in strength, with most of the decline occurring after age 50. The loss of strength is due, in part, to a loss of muscle mass; this age-related loss of muscle mass is termed

sarcopenia

By comparison to the rate of detraining following endurance training, the rate of detraining (i.e., loss of muscular strength) following a resistance training program is _________.

slower

Endurance training results in increased mitochondrial and capillary density in muscle but has no effect on muscle glycolytic capacity. This is an example of what training principle?

specificity

The heart rate and ventilatory responses to constant load submaximal exercise are lower (i.e., lower heart rate and lower minute ventilation) following an endurance training program. This training-induced adaptation is primarily due to changes in the

trained skeletal muscles

Endurance exercise training programs (e.g., 3 days/week @ 60% VO2 max for 12 weeks) typically results in a ______. A) 1-5% improvement in VO2 max B) 5-10% improvement in VO2 max C) 15-25% improvement in VO2 max D)40-60% improvement in VO2 max

c

One disadvantage of studying muscle fatigue in vivo is that ________________. a) these studies only allow the study of fatigue during endurance events b) these studies are not physiological c) these studies often produce correlative data and it is difficult to identify mechanisms d) None of these.

c

Prolonged inactivity of skeletal muscle leads to rapid muscle atrophy; this occurs due to :a. a decrease in muscle protein synthesis b. increased protein breakdown in muscle fibers c. both a decrease in muscle protein synthesis and increased protein breakdown in muscle fibers are correct d. None of these is correct

c

The average VO2 max value for the young (e.g., 21 years old) male sedentary population is approximately A) 22 ml • kg-1 • min-1. B) 35 ml • kg-1 • min-1. C) 45 ml • kg-1 • min-1. D) 83 ml • kg-1 • min-1.

c

Which of the following durations of exercise would environmental factors play the largest role in determining performance? a) events lasting 3-20 minutes duration b) events <10 seconds duration c) events lasting 1-4 hours d) events 10-180 seconds duration

c

Which of the following factors do not contribute to the endurance exercise training-induced improvement in VO2 max? A) increased maximal cardiac output B) increased maximal stroke volume C) increased maximal heart rate

c

Which of the following physiological factors does NOT contribute to the endurance exercise training-induced increase in the maximal a-vO2 difference? A) increased mitochondria volume in the muscle B) increased capillaries in the muscle C) increased hemoglobin in the blood D) increased muscle blood flow

c

The removal of damaged mitochondria in skeletal muscle and other cells is called A) mitogenesis. B) mitophagy. C) mitochondria endocytosis. D) mitochondrial exocytosis.

B

Which of the following factors DO NOT contribute to the endurance exercise training-induced increases in fat metabolism during exercise? A) slower blood flow in muscle B) increased fat storage in the liver C)increased FFA transporters D) increased beta oxidation enzymes

B