2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
Measurement: Ambient temperature
was measured every 30 min, between
13:30 and 17:45. Wet-bulb, black-bulb,
and dry-bulb temperatures and WBGT
were measured using a WBGT meter
(Kyoto Electronics Manufacturing Co.,
Ltd.). The water intake was estimated
using the amounts of water in a
measuring cup marked with a scale of
50 g before and after drinking. Sweat
rate was determined using the equation:
Sweating = (body weight before
practice + water intake) - body weight
after practice.
Among components of the collected blood samples, red blood cells (RBC) were examined by
the sheath flow DC detection method, white blood cells (WBC) by the DC detection method,
the concentration of hemoglobin (Hb) by the SLS hemoglobin method, MCV, MCH, and
MCHC by calculation, hematocrit by the RBC pulse wave detection method, GOT and GPT
by the JSCC method, urea nitrogen by the urease GLDH method, uric acid by the uricase
POD method, myoglobin by the RIA solid-phase method, and creatinine by Jaffe’s method.
Statistics: Results are expressed as mean ±S.D. Student's t-test was used for statistical
treatment of the data. The acceptance level for significance was p < 0.05.
RESULTS
Figure 1 shows the
environmental conditions
during the practice period.
The WBGT at a height of
about 1.2 m in the
playground was 32.8°C at
13:30, when the practice was
started, reached 36.5°C at
15:00, and was 29.8°C even
at 17:45, when the practice
was terminated.
260
Temperature( )
60
50
40
30
Table 1: Characteristics of subjects and resting
values of body temperature
subjects grade height cm weight (kg) body temp
A
B
C
D
E
F
G
H
5
6
5
6
6
6
6
6
137
143
140
140
165
135
135
150
29.6
38.6
32.7
32.2
54.1
30.5
26.7
40.7
37.7
37.5
37.4
37.5
37.4
37.2
37.7
37.7
mean
SD
5.75
0.46
143.13
10.11
35.66
8.77
37.51
0.18
40
20
0
Ta Tg Tw WBGT
20
13:3014:0014:3015:0015:3016:0016:3017:0017:45
Time
Table 2 summarizes the
Figure 1: Environmental conditions in the ground during
baseball practice
hematological
variables before
and after baseball
Table 2: Levels of hematological parameters before and after baseball
practice
practice. The
number of WBC
was significantly
larger after than
before practice (p
< 0.01). However,
there were no
significant
WBC(10 MCHA(g/100m -1RC)
Subjects Before After before after before after before after before after
A 12.3 13.1 465 465 12.5 12.6 38.3 37.7 32.6 33.4
B 6.3 8.1 475 516 13.6 14.8 40.7 43.5 33.4 34.0
C 7.1 10.6 500 502 13.8 14.0 42.1 41.7 32.8 33.6
D 9.0 10.7 499 485 14.1 13.7 43.1 41.4 32.7 33.1
E 6.6 9.7 464 484 13.9 14.6 41.5 42.5 33.5 34.4
F 7.2 8.1 451 465 13.5 13.7 39.4 40.5 34.3 33.8
G 4.7 7.0 457 467 13.6 14.0 40.2 40.5 33.8 34.6
H 7.3 7.3 441 439 13.0 13.0 40.5 39.7 32.2 32.7
Mean 7.56 9.33 469.0 477.9 13.50 13.80 40.71 40.94 33.16 33.70
SD 2.26 2.08 21.40 24.20 0.52 0.74 1.52 1.78 0.70 0.64
4 /μ ) RBC(10 4 /μ ) Hb(g/ ) Ht(%)
Relative humidity(%)