I__. - International Military Testing Association

each item on the SSQ was read to the group by a medical NCO. Each
subject’s ratings were sensed by a lapel microphone and recorded
on a separate audio channel for subsequent data encoding and
analysis. The last (fifth) administration was immediately after
an experimental session. Subjects removed their un i forms and
monitoring equipment and were tested in a room (at normal ambient
temperature) 5 min after they finished walking on the treadmill.
All data were analyzed with SPSS/PC+, V3.0. Results were
significant if ~~0.05 (l-tailed). Data were frequently missing
during a daily test session and often involved different subjects
from administration to administration of an item. Paired T-tests
were used in evaluating uniform ensembles rather than more traditional
repeated-measures, analysis of variance statistics, since . .
this statistic was not affected by missing values which occurred
during another administration in a session,
RESULTS
These data demonstrate responsiveness of the SSQ to heat
strain induced by metabolic heat production from exercise and
high environmental temperatures. These data reflect average sub-
ject responses under conditions of increasing heat storage
induced by walk-rest activities.
Activity-time changes on individual SSQ items dluring
experi-
mental sessions suggested three trends: decreased capabilities
during the session with rapid recovery afterwards (Fig. 1).
decreased capabilities, without rapid recovery (Fig. 2), and no
apparent changes for some capabilities (Fig. 3). Each bar in Fig.
l-3 has a “+I’ symbol above i t ; the hor i zontal bar on each symbol
is the standard error of the mean for that data point. This
report only shows illustrative data because of space limitations.
Analysis of these data for other purposes required use of
multiple comparisons to evaluate various configurations of the
firefighting ensemble for different activities-times during the
session. Table II shows i terns which appear most frequently
affected by these conditions since these i terns were more often
statistically significant for these comparisons.
On some items, perceived capabilities are least during exercise,
e.g. Item 24: “I would have trouble running 2 miles in
anything near my normal t ime”. On other i terns, perceived capabilities
are least during rest following exercise, e.g. Item 35:
“I feel as good as I usually feel”. Most capabi I ities recover
rapidly following exercise and heat exposure since values obtained
5-10 min after the end of the experimental challenge are
simi lar to base1 ine values. A few capabilities recover more
slowly since they are still
tion.
impaired during the last administra-
Missing data were evident for al I conditions but were more
frequent during exercise or when subjects were approaching medical
safety limits or feeling i I I. Although some data were lost
because of equipment and procedural shortcomings, most missing
data were caused by failures of the subjects to respond when they
were uncomfortable or preoccupied with other activities.
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