Energy Concepts
November 2010 paper 32
1 (a) (i) Outline the alactic energy system which is predominantly used by an athlete during a 100
m sprint. [6]
(ii) Describe both the advantages and disadvantages of the alactic energy system. [4]
(iii) Describe a method of performance enhancement that is used to increase the threshold of the
alactic energy system. Give reasons why this method of performance enhancement is used. [4]
1 (a) (i) 6 marks in total sub max 1
1 ATP / PC system / PC system
sub max 5 marks from
2 Anaerobic pathway / without O2
3 Uses phosphocreatine as a fuel / high energy phosphate compound
4 Creatine kinase is the controlling enzyme
5 PC is broken down to P + C + E
6 This is an exothermic reaction / energy is released
7 Energy is used in an endothermic reaction
8 To re-synthesise ADP + P + E ATP
9 The reaction takes place in the sarcoplasm
(ii) 4 marks in total
sub max 2 marks from
1 Very fast / simple reaction / PC small compound found in cell
2 Reaction does not require the presence of oxygen
3 No by-products are produced
sub max 2 marks
4 Only small amounts of PC so limited threshold
5 Only one ATP re-synthesised for each PC / small energy yield
(iii) 4 marks in total
sub max 2 marks from
1 Creatine supplementation
2 Ingesting 20 g / 25 g of creatine per day for 5 to 7 days
3 Better to take creatine combined with glucose
4 Creatine is naturally found in the diet but only in small quantities
sub max 2 marks from
5 Helps maintain ATP concentrations more during maximum effort
6 Improves high intensity performance and repetitive bouts of high intensity work even
more
7 Does appear to promote gains in lean body mass during training
November 2012 paper 31
1 (a) (i) During a 100 m sprint the predominant energy system used is the ATP/PC (alactic)
system.
Describe how energy is released by this system. [5]
(ii) Why is the ATP/PC (alactic) system effective in providing energy during a 100 m sprint?[3]
1 (a) (i) 5 marks in total from:
1 Anaerobic (system) / does not require oxygen
2 Reaction takes place in the sarcoplasm
3 PC is a high energy phosphate compound in the cell
4 PC broken down to release energy
5 Energy then used to resynthesise (ADP to) ATP
6 Reaction controlled by creatine kinase
7 Yield approx 1:1 / 1 ATP produced
8 No fatiguing by-products
9 PC can be resynthesised when exercise intensity drops allowing recovery [5]
(ii)
1
2
3
3 marks in total:
Very fast reaction / energy released (as PC only small compound) / short metabolic pathway
Reaction doesn’t require presence of oxygen
PC readily available (in the muscle / cell for breakdown) [3]
(ii) How can a performer use their knowledge of the alactacid component to their advantage
when training or performing? [3]
(ii) 3 marks from:
1 useful when planning interval sessions / reps and sets
2 for max speed work need to allow enough time for full recovery
3 for endurance work need to allow time for only partial recovery
4 50% of PC stores can be replenished in 30 secs
5 therefore making good use of time-outs / substitutions / full time allocation between games,
etc. is important
6 during stoppage of play taking time e.g. injury / throw in / corner kick
7 changing tactics to lower intensity and gain recovery time
November 2010 paper 3
1 (a) Knowledge of the three energy systems underpins exercise and sport physiology.
(i) Name an energy system and identify the missing information A, B and C for this system. [3]
3 marks in total (from one energy system only)
(ATP/PC system)
1 A = PC
2 B = sarcoplasm/cytoplasm
3 C = creatine kinase
(lactic acid system)
4 A = glycogen/glucose/carbohydrate
5 B = sarcoplasm/cytoplasm
6 C = glycogen phosphorylase/phosphofructokinase/PFK/lactate dehydrogenase/LDH (aerobic
system)
7 A = glycogen/glucose/fats/carbohydrate
8 B = sarcoplasm/mitochondria
9 C = glycogen phosphorylase/phosphofructokinase/PFK/lipase
(ii) Sketch a graph of energy supplied against time to show when each of the three energy systems
is predominant in relation to duration of exercise. [3]
3 marks in total
1 ATP-PC system/alactic system correctly sketched and labelled
2 lactic acid system correctly sketched and labelled
3 aerobic system correctly sketched and labelled
November 2013 paper 31
1 (a) The 2012 Olympic Men's 400 metre title was won with a time of 43.94 seconds.
Describe how the energy is provided to run a 400 metre race.
6 marks for 6 of:
1. Anaerobic / without oxygen / sarcoplasm
2. (Initially in first few seconds) stored ATP splits/breaks down
3. ATP breaks down to ADP + P + energy
4. ATP-PC system / phosphocreatine system / alactic system
5. PC = C + P(i) + energy/creatine + phosphate/PC broken down;
6. Energyused for ATP resynthesis / ADP + P + energy = ATP/ADP + PC = ATP + C
7. Lasts 5–10 seconds / first 80-100 metres of race
8. Lactic acid system / Lactate anaerobic system /anaerobic glycolysis
9. Glycogen/glucose breakdown
10. …by enzyme phosphofructokinase / PFK / glycogen phosphorylase / GPP
11. Forms pyruvate / pyruvic acid
12. Lactate / lactic acid formed