2007, Piran, Slovenia

Cognitive and Psycophysiological Function
eliciting 80% HRR (Run 1), a brief pause for blood sampling, then a 30-min running
distance trial (Run 2, blood sample at end), and finally another 15-min cycle as per
Cycle 1. Participants returned to the lab five hours post-exercise to do a final
cognitive assessment. Ratings of perceived exertion (RPE), thermal discomfort
(TDC), thermal sensation, (TSen) and heart rate (HR) were recorded throughout the
exercise protocol.
Integrity of the BBB was estimated from plasma concentration of S100β, assayed
using ELISA. Cognitive function was assessed using the Stroop colour and word test
at baseline, Cycle 1, Cycle 2 and 5-hr post exercise. The Stroop test assesses cognitive
executive function by presenting coloured stimulus words which are the names of
colours, thus generating conflict between naming recognition and colour recognition.
The test had four levels of increasing complexity, with 20 trials per level. It was
completed on a computer with a black background; participants were asked to respond
to stimuli as quickly and accurately as possible by pushing the left or right arrow key
according to their selection. Levels One and Two represented simple responses
because participants read a word (either “red”, “green”, “yellow” or “blue”) written in
white (Level One, simple task), or named the colour of a bar (Level Two). Levels
Three (Figure 1) and Four involved recognition conflict; responding to the colour (not
name) of the word. Level Four was the most complex because each of the two
response words were themselves written in different colours. Performance was
recorded as mean speed for the last 19 of 20 trials in a
block, accuracy of response, and variability of
response time within a block as a potential index of
attention. Because response times contain central and
peripheral components, the difference in response
time between Level One and Level Four was
calculated and assumed to represent central processing
time. Participants completed a minimum of 5 practice
Figure 1- Example of a
Stroop colour-word test
screen (Level Three).
tests in their familiarisation trial.
Because data from both trials were pooled, a mixedmodel
analysis of variance with one within-subjects
factor (time; 5 levels) and one between-subjects factor
(fitness) was used (with Sidak post-hoc analysis;
P