DISCUSSION
The changes in tension state after an acute
bout of exercise found in the current study
are consistent with previous research
demonstrating the psychological boost
exercise can provide. Surprisingly, while
acute exercise typically reduces stress, in
our study it increased feelings of tension
post-exercise. Further exploration showed
that this change was associated by an
interaction of gender by experimental
environment condition. Women felt the
more tense post-exercise, although they
exercised the most intensely, in the mirror +
poster condition. Men felt the more tense
after exercising in front of a mirror alone,
and the fitness poster images did not
impact their mood. This is consistent with
research showing that ideal body image
exposure may put females at a unique risk
(6, 8). These results indicate that the
presence of a mirror and ideal media
images may be detrimental to the potential
tension reduction that acute exercise has to
offer, especially for females.
The gender differences in tension by
condition are noteworthy. Women felt less
tense than men in the mirror only
condition; it was only when the presence of
an ideally fit female body was placed
alongside the mirror reflection that women
felt most tense. It is plausible that the poster
primed self-comparison, a phenomenon
women are especially vulnerable to (10).
Future studies should include a measure of
self-comparison. One possibility is asking
participants to indicate the position of their
perceived actual self and perceived ideal
self on a fitness scale. We would
hypothesize the gap would be greater for
men in the mirror only condition, and
greater for females in the mirror + poster
condition.
We do not have an explanation for why
exercise exertion is not correlated with
feelings of tension. There may be a
personality variable explaining why the
mirror + poster condition may be inspiring
for some women, but tension inducing for
others. Future studies should investigate
what personality traits may buffer
potentially detrimental characteristics of
exercise environments.
There are several limitations of the current
work. The study was conducted at a
private, West Coast university where the
culture is generally one of fitness and high
physical activity. However, this is
conservative to the hypotheses; it is
possible the effects would be more
pronounced in a population where regular
exercise and fitness was not the norm. Also,
the study was conducted in a laboratory
setting; in a gym there are arguably many
other types of stimuli in view during
aerobic activity. It could be argued,
however, that only a mirror and two
posters is conservative compared to a gym
environment; there would be not only more
mirrors and more fitness images (on TVs
and in magazines), but also actual fit others,
which could amplify the mood and
physical outcomes we found in the present
laboratory based study environment.
Finally, a limitation of the current design is
that baseline emotions were assessed in the
lab room, where participants could see a