Exercise Physiology Questions and Answers

Answer: B

The valve is the tricuspid valve.

The tricuspid valve lies between the right atrium and the right ventricle. When the right ventricle contracts, the rising pressure closes it, so blood cannot flow back into the atrium and is driven instead through the pulmonary valve into the pulmonary artery.

The bicuspid (mitral) valve does the same job on the left side, between the left atrium and left ventricle. The pulmonary valve opens, not closes, when the right ventricle contracts, and the vena cava is a vein, not a valve.

Answer: C

The key gives 6 times normal.

In extremely hot weather an active person loses large amounts of water as sweat, so fluid intake must rise well above the ordinary daily need. The keyed multiple is six.

I could not confirm the figure of six times normal in any source I could reach; sports-nutrition sources give absolute losses instead (a litre or more of sweat an hour in the heat, and several litres a day), which depend on the person and the conditions and are not stated as a multiple. Nothing found shows the key wrong, so it is kept. A rise of only two or three times looks too small for extreme heat and ten times looks too large.

Answer: A

The temperature interval is 14.5°C to 15.5°C.

The heat needed to warm water varies slightly with temperature, so the calorie was defined precisely as the heat required to raise one gram of water from 14.5°C to 15.5°C, the '15-degree calorie', equal to about 4.186 joules. The kilocalorie (1,000 calories) is the 'Calorie' used for food energy.

Other definitions exist, for example the mean calorie from 0°C to 100°C, but 0°C to 1°C, 20.5°C to 21.5°C and body temperature, 37°C to 38°C, are not the reference interval.

Answer: C

The one that is not a fatty acid is ascorbic acid.

Ascorbic acid is vitamin C, a water-soluble vitamin with a sugar-like ring structure, needed for collagen formation; its deficiency causes scurvy. It is not a fatty acid.

The other three are fatty acids, long hydrocarbon chains with a carboxyl group, found in fats and oils. Stearic acid and palmitic acid are saturated fatty acids, and oleic acid is a monounsaturated fatty acid, the main fatty acid of olive oil.

Answer: B

Laboured breathing is called dyspnea.

Dyspnoea is difficult or laboured breathing, the feeling of breathlessness. It is normal during hard exercise but abnormal at rest, where it can signal heart or lung disease or poor fitness.

VO2 max is the maximum rate of oxygen uptake, a measure of aerobic capacity. Vital capacity is the largest volume of air that can be breathed out after a maximal breath in. Second wind is the sudden relief from breathlessness and fatigue that can come during prolonged exercise, the opposite of laboured breathing.

Answer: C

FTa fibres are oxidative-glycolytic.

Skeletal muscle fibres are classified as slow-twitch (type I), which are oxidative, and fast-twitch (type II). The fast-twitch type IIa (FTa) fibres are fast oxidative-glycolytic: they contract quickly and can produce energy both aerobically and anaerobically, so they are fairly resistant to fatigue.

The fast-twitch type IIx (or IIb) fibres, FTb, are the purely glycolytic ones, powerful but quick to tire. Purely oxidative describes slow-twitch fibres, and FTa fibres are a well-defined type, so 'unclassified' does not fit them.

Answer: C

The BMR is about 5 to 10 percent lower in women than in men.

Basal metabolic rate depends largely on the amount of lean, metabolically active tissue. Women on average have a higher proportion of body fat and less muscle mass than men of the same body weight, so their BMR is roughly 5 to 10 percent lower, even when expressed per kilogram of body weight.

The options saying 'higher' reverse the direction, and a difference of 40 to 60 percent is far larger than the real gap between the sexes.

Answer: C

The one that is not an effect of anabolic androgenic steroids is weight loss.

Anabolic androgenic steroids are synthetic derivatives of testosterone. Their anabolic action increases protein synthesis and muscle mass, so they cause weight gain, not weight loss.

Their androgenic side effects include acne from increased sebum production, growth of facial and body hair (especially in women), and male-pattern scalp hair loss. Other effects include liver damage, adverse changes in blood cholesterol, testicular atrophy and mood changes.

Answer: D

Pangamic acid is called Vitamin B-15.

Pangamic acid was promoted from the 1950s, especially in the Soviet Union, as 'vitamin B15' and claimed to improve oxygen use and endurance in athletes. It is not a true vitamin: no deficiency disease is known and its composition varies between products, but in sports nutrition texts it is listed under that name.

Vitamin B-1 is thiamine, Vitamin B-6 is pyridoxine and Vitamin B-12 is cobalamin; none of them is pangamic acid.

Answer: B

The compound is cholesterol.

Cholesterol is a fat-like sterol found in all animal tissues and made by the liver. It is needed for cell membranes and for making steroid hormones and bile acids. High levels of LDL cholesterol in the blood lead to deposits (plaques) in the walls of arteries, the process of atherosclerosis, which narrows them and raises the risk of heart attack and stroke.

Glucagon is a pancreatic hormone that raises blood sugar, cortisol is an adrenal stress hormone and glucose is a simple sugar. None of them is fat-like or the substance deposited in atherosclerotic plaques.