I’ve got the power

How does the body respond to changing energy needs?

Lesson 1

Experiment A: How much power do my muscles generate?

Each group will need:

Equipment / Comments
From school
1 stopclock
1 gym bench/aerobic step/ sturdy box/stair / height 0.25–0.3 m
bathroom scales / in case students forget to measure their mass at home
1 ruler, metre / to measure step height
metronome / optional – to help keep time
music / optional – to help keep time
tally counter / optional – to keep a tally of repetitions completed

Lesson 2 – Carousel of experiments

The tables below show the equipment required for one station for each experiment withinthe carousel. Depending upon the equipment available to each class and the number ofstudents in the class, you may wish to provide more stations for one or more of the carouselexperiments.

Experiment B: What does being fit mean?

Each carousel workstation will need:

Equipment / Comments
From kit box
1 pulse oximeter / requires 2 × AAA cells. Do not use lithium cells and avoidmixing different types, e.g. zinc chloride and alkalinerefer to page 7 ‘How to use the equipment in the box’ in thisguide for instructions
1 tape measure / stadiometers could be used for measuring standing heightinstead
From school
1 stopclock
1 gym bench/aerobic step/ sturdy box/stair / height 0.25–0.3 m, and higher if possible
stadiometer / optional – tape measures could be used instead
metronome / optional – to help keep time

I’ve got the power

Experiment C: Does carbon dioxide increase in my breath after exercise?

Each carousel workstation will need:

Equipment / Comments
From kit box
1 respirometer pack (1 plastic 2-litre bottle, bung, piece of plastic tubing, piece of flexible tubing, one-way valve) / refer to the diagram on page 89 of this guide for assemblyinstructions
one piece of flexible tubing in the kit box has the valve fittedfor extra stations, the flexible tubing will need to be cut inhalf (2 × 12.5 cm lengths) and rejoined with the valve in themiddle of them; the ends screw in
bromothymol blue indicator solution (low hazard) / 5 g provided in kit as a solid
prepare a stock solution of 0.1% bromothymol blue:
●0.3 g bromothymol blue dissolved in 150 ml deionised water.
●To obtain 1 litre of working solution, dilute 30 ml of stock solution to 1000 ml with deionised water.
●The solution may appear blue or green depending on the pH of the stock water. To adjust the colour to just green (neutral) add 0.1 M sodium hydroxide drop wise but do not add to excess.
●Each group will require 1500 cm3 of working solution. The quantity of stock solution above will produce 10 litres of working solution, enough for six groups.
0.1 M sodium hydroxide solution / each group needs less than 20 cm3
add a label to each bottle, before giving to students to use, indicating that it is an irritant
1 indicator chart / for colour comparison of bromothymol blue
pipette, 3 ml / for measuring the volume of sodium hydroxide solution added (5 cm3 is required, so students will have to refill the pipette)
From school
1 stopclock
safety goggles (1 per student)
disinfectant or sterilising solution / to sterilise flexible tubing before and after each usedisinfectant must always be freshly prepared prior to use andmust be active against viruses e.g. chlorine-based such as adiluted bleach solution or a persulphate compound such asVirkon™
tubes should remain in the disinfectant for 24 hours and wellrinsed prior to next use
2 test tubes
1 test tube rack
1 measuring cylinder / to measure out 500 cm3 of bromothymol blue solution
empty, washed, 2 litre plastic bottle / the kit box includes 1 plastic 2-litre bottle; depending onhow many stations you set up for Experiment C you will need more cola-type drink bottles
1 skipping rope / optional
1 gym bench/aerobic step/ step stool/sturdy box/chair / height 0.25–0.3 m, optional
video clip of Zumba® or CD
of fast dance music / optional

Experiment D: What happens to my heart rate and blood pressure when I exercise?

Each carousel workstation will need:

Equipment / Comments
From kit box
1 pulse oximeter / requires 2 × AAA cells. Do not use lithium cells; avoid mixing different types, e.g. zinc chloride and alkaline
refer to page 7 ‘How to use the equipment in the box’ in this guide for instructions
1 blood pressure monitor / requires 1 × AA 1.5 V cell
refer to page 10–11 ‘How to use the equipment in the box’ in this guide for instructions
From school
1 stopclock