| Date | May 2013 | Marks available | 1 | Reference code | 13M.3.SL.TZ2.4 |
| Level | Standard level | Paper | Paper 3 | Time zone | Time zone 2 |
| Command term | Calculate | Question number | 4 | Adapted from | N/A |
Question
An investigation was conducted among competitive swimmers to determine the effects of two different training programmes.
Swimmers were encouraged to maintain an even pace throughout the programmes. The pace was slightly slower in the 3000 m programme than in the 6000 m programme.
Tissue samples were taken from the shoulder muscle of each swimmer, before and after each session. Glycogen levels were analysed in slow (type I) muscle fibres.
Calculate the percentage of slow (type I) muscle fibres that contain low levels of glycogen after the 3000m programme.
State the effect of the 3000 m programme on glycogen levels in slow (type I) muscle fibres.
Compare the effects of the 3000 m programme with the 6000 m programme on muscle glycogen levels.
Suggest reasons for the differences between the 3000 m programme and the 6000m programme in their effects on muscle glycogen levels.
Suggest one limitation of the data.
Markscheme
50 (%)
reduces glycogen levels
a. both lower the glycogen level;
b. much greater reduction with 6000 m programme;
c. no moderate (glycogen) levels exist after 6000 m programme / far more with no glycogen;
a. lower levels after 6000 m programme because more energy needed for longer swim;
b. lower levels after 6000 m programme because the pace of swimming was faster;
c. blood systems cannot supply glucose as fast as it is used during intense exercise;
d. slow (type I) muscle fibres only have moderate stamina so are not ideal for faster swimming;
e. less aerobic in 6000 m programme / vice versa;
a. no measurement of glycogen levels in fast/type II muscle fibres;
b. no mention of sample number/sex;
c. data shows no SD or SE;
Examiners report
Almost all could state 50% for a.
In b, the command term was state, but many tried to explain at length, usually on extension sheets.
In c i and ii most were able to obtain 1 mark, with only the better candidates obtaining both.
In c i and ii most were able to obtain 1 mark, with only the better candidates obtaining both.
Many were able to obtain the mark in d for stating that there was no mention of the sex of the swimmers or comparison of fitness.
