Identify the time and condition with the highest mean sprint speed.

Calculate the difference in mean sprint speed, in m s^–1, between baseline and at 4 minutes for the plyometric condition.

Using the data, discuss the hypothesis that plyometric exercise can improve sprint performance.

Explain the reason for using a control condition in this study design.

8 minutes
AND
plyometric ✔

[1]

6.75 – 6.55 ✔
= 0.20 «m s^–1» ✔

Accept calculations in the reverse.
Consider ECF 

[2]

plyometric exercise improved performance / hypothesis is supported ✔
The t-test supports the hypothesis that plyometric exercise improves performance with p<0.05 «at 4 minutes» ✔
plyometric exercise did not improve performance prior to 4 minutes ✔
plyometric exercise was less effective after 8 minutes / plyometric condition speed increased/was better than the control up to the 12-minute test period ✔

For mark point 1, accept the use of the actual data for discussion. Also the reason for the judgement needs to relate to the data.

[2 max]

the control condition allows for a comparison point for the experimenter to compare the subjects speed with
OR
shows if there is an effect of the plyometric condition compared to walking only ✔

a control allows one factor to be investigated while all others are kept constant
OR
there are confounding variables in comparing outcomes with baseline data ✔

the control condition allows the researcher to determine warm-up / fatigue effects ✔

control condition increases «internal» validity ✔

[2 max]

The calculations and interpretation of the graph was generally very well done. 

The calculations and interpretation of the graph was generally very well done. 

Discussion of the hypothesis and use of control was adequate with most students earning at least one of the two marks on offer. However, candidates often supported the hypothesis without using the paired t-test p value given, suggesting that they did not understand this statistical concept. Many proposed the hypothesis describing generalities of plyometric muscular contraction without providing supporting data – indicating that they did not read the question properly.