A company has developed a drink to improve the performance of athletes during endurance events, such as the Tour de France cycling race.

Describe four study design features which could be used in an experiment to test if the sports drink is beneficial to endurance performance.

Discuss how you would use the key principles of training to help you prepare for a long-distance cycle race.

Outline six cardiovascular changes that would be expected as a result of an endurance cycling training programme.

Explain the physiological changes which contribute to a person experiencing cardiovascular drift during an endurance event such as the Tour de France.

control groups:
they will need to have a group that does not receive the condition/sports drink <and a group that will receive the condition> ✔

randomization:
subjects will be randomly allocated to receive the drink condition and the control ✔

placebos:
the experimenter will try to ensure that a placebo effect is avoided by using a drink which in all ways matches the real drink they are testing so that subjects cannot tell the difference ✔

blinding:
the subjects will not know that they are receiving the real drink or the placebo/blinding eliminates subjects being affected by the placebo effect ✔

double-blinding:
the experimenter will not know which drink each subject is consuming so that they are not unduly influencing the subjects behaviour / performance ✔

statistical analysis:
once they have collected the data the experimenter will use statistical tests/t-tests/anova/to help establish whether the effect from the drink is statistically significantly different from the control/placebo ✔

Award [1 max] for each feature.

progression:
gradually build up the distances ridden over time ✔

gradually build up the pace ridden over time ✔

overload:
cycling further than previously done to put strain on the body ✔

frequency:
build up the frequency of rides so that you may be riding every other day ✔

ensure that there is a good balance between training days and rest days to allow recovery ✔

duration:
gradually build up the duration/time cycling so that the body is used to the distance needed ✔

push the training time beyond what you are normally training/beyond the event time so that you will cope on the day ✔

intensity:
gradually build up the riding speed over the distances so that you are maximizing this aspect ✔

train on hills/have periods of high intensity effort and periods of recovery on a training ride ✔

variety:
train/cycle in a variety of different environments e.g.: hills, flat; spinning (gym) ✔

periodization:
plan the programme to develop endurance for the first few weeks followed by speed endurance ✔

specificity:
training should mimic performance / movement / muscle groups / energy systems / etc. ✔

reversibility:
be conscious that if no training occurs for whatever reason then training effects will slowly diminish ✔

Award [2 max] for each principle.

Note: principle doesn’t need to be named; description of principle is sufficient.

increased left ventricular volume/an increase in stroke volume ✔

lower resting heart rate ✔

lower exercising heart rate <when completing the same submaximal task> ✔

increased maximal level cardiac output ✔

increased capillarization to lungs and trained muscles ✔

increased red blood cell count ✔

increased myoglobin in muscle cells ✔

increased mitochondrial density ✔

increased arterio-venous O₂ difference ✔

increased plasma volume ✔

a rise in body temperature which causes blood flow to be diverted to the skin ✔

this increased blood flow away from working muscles puts increased strain on the heart to pump harder / faster ✔

loss of blood plasma due to the sweat process which reduces blood volume / stroke volume ✔

therefore increases heart rate to maintain cardiac output ✔

this reduced blood volume makes the heart work harder due to there being less blood and increased viscosity ✔

5(a), (b) and (d) The knowledge in each of these questions was quite poor. Sometimes candidates could name the features but not describe or apply them to a situation.

5(a), (b) and (d) The knowledge in each of these questions was quite poor. Sometimes candidates could name the features but not describe or apply them to a situation.

Candidates gained marks for aspects which revolved around the heart but they were less likely to mention deeper aspects such as red blood cell or mitochondrial changes.

5(a), (b) and (d) The knowledge in each of these questions was quite poor. Sometimes candidates could name the features but not describe or apply them to a situation.