dcf.cymru stimulus sheet · PE · Year 10

Afon Harriers: the training zones model pack

The club, the coach, the athletes and their heart rates are invented. The science is real: the formula, the zones and the energy systems are the ones in the WJEC GCSE Physical Education and Health specification, Unit 1, section 1.2.4.

1. The problem

Coach Mari Lloyd runs a junior running club in the Cynon Valley. She wants every athlete to train in the right heart rate zone for each session. She built a spreadsheet model: you type in an athlete’s age, and it works out their maximum heart rate and the heart rates that mark the edges of each training zone. Several athletes now wear heart rate watches, so she can check whether each session hit the zone she planned.

Mari is not sure her spreadsheet is right. Some of the numbers “look odd”.

2. Fact card: training zones and thresholds

Maximum heart rate (MHR) = 220 − age. It is an estimate, measured in beats per minute (bpm).
Aerobic training zone: 60% to 80% of MHR. Training here improves cardiovascular fitness.
Aerobic threshold: 60% of MHR, the point where you enter the aerobic zone. Below it, exercise still helps health but gives little training improvement.
Anaerobic training zone: 80% to 90% of MHR. Much higher intensity, so it can only be kept up for short periods.
Anaerobic threshold: 80% of MHR, the point where you enter the anaerobic zone.
Above 90% of MHR is close to maximal effort.

3. Fact card: the three energy systems

All three systems work all the time. In any activity one of them is predominant (does most of the work), depending mainly on how hard and how long the effort is.

	Creatine phosphate (CP) system	Lactic acid system	Aerobic system
Intensity	Highest	High	Low to moderate
Duration	Up to 10 seconds	10 seconds to about 3 minutes	Long periods
Oxygen?	No	No	Yes
Fuel and waste	Creatine phosphate stored in the muscles. No waste products.	Carbohydrate (glycogen) stored in the muscles. Makes lactic acid, which causes tiredness.	Carbohydrates and fats. Slower, but can last a long time.
Examples	100 m sprint, shot put, a jump	400 m run, a long attacking move	Jogging, long-distance running and cycling

4. Mari’s spreadsheet, version 1

Values view, what Mari sees. The sheet shows each result rounded to the nearest whole number.

	A	B	C	D	E	F	G
1	Name	Age	Resting HR	Max HR	Aerobic threshold (60%)	Anaerobic threshold (80%)	Top of anaerobic zone (90%)
2	Nia	16	64	204	122	163	184
3	Owain	17	58	237	142	190	213
4	Priya	14	70	206	12	165	185
5	Dafydd	13	72	207	124	166	185
6	Mari (coach)	42	60	180	108	144	162

Formula view, what is really in each cell. Columns A, B and C are typed in.

	D	E	F	G
2	`=220-B2`	`=D2*0.6`	`=D2*0.8`	`=D2*0.9`
3	`=220+B3`	`=D3*0.6`	`=D3*0.8`	`=D3*0.9`
4	`=220-B4`	`=D4*0.06`	`=D4*0.8`	`=D4*0.9`
5	`=220-B5`	`=D5*0.6`	`=D5*0.8`	`=D4*0.9`
6	`180`	`=D6*0.6`	`=D6*0.8`	`=D6*0.9`

5. Last week’s sessions, from the heart rate watches

Athlete	Session	Heart rate recorded
Nia (16)	Sunday steady run: 40 minutes at a pace where she could still talk in short sentences.	Average 150 bpm
Owain (17)	6 hard repeats of 300 m. Each repeat took about 50 seconds, with 3 minutes’ walk between.	174 bpm at the end of each repeat (average)
Priya (14)	8 flat-out 30 m sprints from a crouch start. Each took about 5 seconds, with 2 minutes’ rest between.	140 bpm at the end of each sprint (average)
Dafydd (13)	800 m race at the county schools meeting, finished in 2 minutes 40 seconds.	190 bpm as he crossed the line
Mari (42)	30 minutes of walk-jog while coaching the youngest group.	Average 107 bpm

Mari’s note: “My sheet says my aerobic threshold is 108, so 107 means I did not even get into the aerobic zone. Priya’s 140 is in her aerobic zone, so her sprint session was an aerobic session. Is that right?”