77 exam-style questions on Transport — topic A.1.3 of Exercise physiology and nutrition of the human body in the IB Sports, Exercise and Health Science syllabus — with answers and explanations. Samples below; the full set is free with an account.
A cyclist's cardiac output rises from 5.0 L min-1 at rest to 25.0 L min-1 at maximal effort. Which pair of changes accounts for this rise?
Answer: Increases in both heart rate and stroke volume
Cardiac output is the product of heart rate and stroke volume and both rise with intensity, although stroke volume plateaus well below maximum. The a-v oxygen difference widens as well, but that changes extraction by the muscle, not the volume pumped.
Which mechanism makes the largest contribution to venous return during steady running?
Answer: The skeletal muscle pump squeezing the deep veins
Rhythmic contraction of the leg muscles compresses the deep veins while one-way valves keep the blood moving towards the heart. This is why a runner who stops dead after a race may feel faint as venous return collapses.
In the capillaries of a marathon runner's working muscle the oxyhaemoglobin dissociation curve shifts to the right. What is the effect of this shift?
Answer: Oxygen is unloaded more readily at the muscle
The higher temperature, carbon dioxide and hydrogen ion concentration of exercising muscle lower haemoglobin's affinity for oxygen, the Bohr effect, so more oxygen is released where it is needed. The quantity of haemoglobin, and therefore carrying capacity, is unchanged.
A rower breathes 32 times per minute with a tidal volume of 2.5 L during a 2000 m test. What is her minute ventilation?
Answer: 80.0 L min-1
Minute ventilation = tidal volume x breathing frequency = 2.5 x 32 = 80 L min-1. Dividing instead of multiplying gives 12.8, adding the two figures gives 34.5, and 8.0 is the same product with the decimal point misplaced.
At the same submaximal power output on a cycle ergometer, a rider has a stroke volume 25 % higher and a heart rate 20 % lower than a training partner of the same body size. Which statement about her cardiac output at that power output is correct?
Answer: It is the same as her partner's, because 1.25 x 0.80 = 1.00.
Cardiac output is a product, not a sum, so percentage changes multiply: a factor of 1.25 for stroke volume and 0.80 for heart rate returns exactly 1.00. The common error is to add or subtract the percentages.
A student calculates the cardiac output of a swimmer whose heart rate is 168 bpm and whose stroke volume is 125 ml, and writes the result as 21 000 L min-1. Identify the error in that piece of work.
Answer: She left the product in millilitres per minute and labelled it litres per minute.
The arithmetic is right but the units are not: 168 x 125 = 21 000 ml min-1, which is 21.0 L min-1. Any cardiac output far outside roughly 4 to 40 L min-1 should prompt a check of the units before the answer is written down.
That was 6 of 77 Transport questions.
Practise all 77 freeOutlineAO2 · 1–4 marks
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Give a detailed account of what it is or how it happens — steps, features, pattern — without saying why.
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A labelled, accurate drawing with a ruler where lines are straight; axes and units on a graph.
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77 Transport questions — free with an account. Spaced repetition, streaks and full exam simulations included.
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