Photo AI

The heart rate and stroke volume of a 40 year old cyclist were monitored as he used an exercise bike - Scottish Highers Human Biology - Question 8 - 2015

Question icon

Question 8

The-heart-rate-and-stroke-volume-of-a-40-year-old-cyclist-were-monitored-as-he-used-an-exercise-bike-Scottish Highers Human Biology-Question 8-2015.png

The heart rate and stroke volume of a 40 year old cyclist were monitored as he used an exercise bike. The cyclist was told to pedal at a constant rate as his work l... show full transcript

Worked Solution & Example Answer:The heart rate and stroke volume of a 40 year old cyclist were monitored as he used an exercise bike - Scottish Highers Human Biology - Question 8 - 2015

Step 1

Use data from the graph to describe the changes that occurred in the cyclist's stroke volume when the work level increased from 1 to 7 units.

96%

114 rated

Answer

Between work levels 1 to 5, the stroke volume increased steadily. It went from 88 cm³ to 140 cm³ by work level 5, indicating that as the cyclist pedaled harder, his stroke volume increased. Beyond work level 5, it remained constant at 140 cm³.

Step 2

State what the cyclist's heart rate was when his stroke volume was 120 cm³.

99%

104 rated

Answer

At a stroke volume of 120 cm³, the cyclist's heart rate was 102 beats/min.

Step 3

Calculate the cyclist's cardiac output when his work level was 6 units.

96%

101 rated

Answer

Using the formula for cardiac output:

extcardiacoutput=extheartrateimesextstrokevolume ext{cardiac output} = ext{heart rate} imes ext{stroke volume}

From the graph, at work level 6, the heart rate is 120 beats/min and the stroke volume is 140 cm³:

extcardiacoutput=120extbeats/minimes140extcm3=16800extcm3/extmin ext{cardiac output} = 120 ext{ beats/min} imes 140 ext{ cm}^3 = 16800 ext{ cm}^3/ ext{min}

Step 4

Use information from the table and the graph to determine the work level that the cyclist should maintain in order to metabolise fat.

98%

120 rated

Answer

To metabolise fat, the cyclist should maintain a heart rate of at least 123 beats/min, corresponding to work level 3.

Step 5

Use information from the table to predict the minimum heart rate for improving the fitness of a 70 year old.

97%

117 rated

Answer

For a 70 year old, the minimum heart rate for improving fitness is estimated to be 120 beats/min.

Step 6

Use the table to calculate the percentage decrease that occurs between the ages of 10 and 60 years.

97%

121 rated

Answer

The minimum heart rate for improving fitness decreases from 168 beats/min at age 10 to 124 beats/min at age 60. The percentage decrease can be calculated as follows:

ext{Percentage decrease} = rac{168 - 124}{168} imes 100 = 26.19 ext{%}

Join the Scottish Highers students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;