334
Journal of the Royal-Society of Medicine Volume 85 June 1992
Health of
a
team competing in the 1990 World Solar Car Challenge
R G Moorhead ERCGP DCM C Laurence BA Smart Road, Modbury SA 5092, Australia
General Practice Teaching Unit, Modbury Hospital,
Keywords: solar car; Nottingham Health Profile; International Classification of Primary Care
Summary The health of a team participating in the 1990 World Solar Car Challenge was recorde for 10 of the 11 race days. Morbidity was collected during daily consultations with the team doctor and the diagnoses were later converted to the ICPC code. Team members' self-perceived health status was also recorded daily, using the Nottingham Health Profile. Team drivers consulted the doctor more often than the support staff and the three full-time drivers had significantly more diagnoses than the support staff. The Nottingham Health Profile scores on sleep, energy and emotional reactions showed correlations between higher minimum temperatures and sleep for all team members and for the three full-time drivers, there were significant correlions bet-ween increasig maximum temperatures and emotional reaction sores. The morbidity records and perceived health scores reflect the conditions ofthe race. Twenty-five per cent offull-time driver consultations dealt with skin, eyelid or finger infections probably caused by the lack of washing water. The scores on sleep and emotional reactions were affected by temperature and previous research reports degradation in concentration and dual tasks with increasing temperature. This may account for the difficulty some drivers had in continuing their shifts. Close supervision of the drivers and the recording of their perceived health status helped reduce the health problems ofthe team. Introduction The World Solar Car Challenge was held in Australia in November 1990 and attracted competitors from many countries. Solar vehicles raced 3000 kilometres from Darwin to Adelaide through harsh conditions (Figure 1). The climates encountered on the race trip were initially tropic humid savannah, dry steppe and for most of the journey dry desert. Crews had to contend with approaching and overtaking road trains (three unit semi-trailers), small tornado-like dust storms (which completely destroyed one solar car) and temperatures at road level of over 50°C. In this hot environment they planned and executed their racing tactics. High temperature has been linked to such psychological parameters as irritability, outbursts of temper, negativity of reactions to others1-3, reduced performance, social attraction and helping4. It has historically been associated with collective violence in American cities5'6. Archival data has suggested an association between ambient temperature of around 30°C and such violence. However, increments of temperature beyond this were associated with decreasing incidence of violent events and a duration of 7 days high temperature preceded violence. The ability to perform
Figure 1. The 1990 World Solar Car Challenge showing the distance travelled by the team each day
in hot environments has also attracted industrial7
and military interest8. The health of one solar car team in this race was studied and a correlation made between temperature and self perceived health. The aim of the study was to assess the perceived health of team members, record the morbidity at the doctor patient consultation on a daily basis and also to correlate members' sleep, energy and emotional scores against temperature. Method Car 18, 'Eos' had a team of 18 people, one of whom 0141-0768/92/ was an author in the capacity of medical officer. Eight 060334-04/$02.00/0 students (mean age 17 years) from an Adelaide girls i 1992 school, Annesley College, drove the vehicle for 12 The Royal days. Power of 1100 watts from the solar array via Society of lead acid batteries drove a one horse power electric Medicine
Journal of the Royal Society of Medicine Volume 85 June 1992
motor to give an average speed of 35 km/h (maximum 73) and an average distance of 270 km a day. Because of the need for lightness the vehicle carried no airconditioning. Racing rules demanded a stop every evening at 17.00 h and a morning start at 08.00 h. This left the team in non-racing time in the desert under canvas and hence created long periods of exposure to high temperature. Every team member filled out part one of the Nottingham Health Profile9 (often with the aid of a torch) each evening after eating. Sleep, energy and emotion scores from this profile were correlated with the dry bulb temperatures taken at the weather station of the Northern Territory and South Australia Bureau of Meteorology closest to the team each 24 h. The morbidity at the morning and evening surgery (conducted around the open boot of the lead vehicle of the convoy) was recorded and coded according to the International Classification of Primary Care'0.
29 26
T E m P E R A T U R E
I
x
x
x
x
x
x
r,
x
Is
lo
20
soT o S 70 S 40 SLEEP DISTURBANCE SCORE
3
o
Figure 2. All team members - sleep and temperature
x
Results The team took 12 days to complete the journey and in all but the last 2 days the maximum temperature ranged from 320C to 430C. Health data were recorded for every day except the last one. There were eight drivers (three full-time and five relief) and 10 support staff (nine full-time and one relief). The relief personnel were flown in 4-7 days after the race had started to ease the drivers' workload. Sixty-three per cent of all drivers consulted the doctor on the trip compared with 50% of the support staff (not significant). All drivers generated 26 consultations as compared with six for the support staff (not significant). The diagnoses at these consultations fitted the rubrics in the classification ICHPPC-2-Defined" and were converted to ICPC code'0 (Table 1). There were 35 diagnoses made at consultation for all drivers and eight for all support staff (not significant). Most of the consultations came from the three fulltime drivers who had the longest exposure to driving the solar car. They had 24 consultations compared with six from the nine full-time support staff and there was a significant difference (Mann-Whitney U=0, P=0.01) in whether they consulted or did not consult compared with the full-time support staff. There were 32 full-time driver diagnoses compared Table 1. Diagnoses made at doctor-patient contact
ICPC code Diagnoses A04 Tiredness D93 Irritable bowel syndrome S10 Boils L79 Sprained foot R06 Epistaxis N02 Tension headache N89 Migraine F72 Stye S17 Abrasion S18 Laceration S92 Heat rash S12 Insect bite Other
Total
x T
E
24
-
x
x
-
M
x E
na
R A U
R E Is
is
14
O
tO
2
30
40
70
s
80
I00
itO
11 0
SLEEP DISTUR13ANCE SCORE
Figure 3. All drivers sleep and temperature -
with seven support staff diagnoses from these consultations, which was significant (Mann-Whitney U=0, P=0.01). The Nottingham Health Profile generated perceived health data on sleep, emotional reactions and energy. There was a correlation between higher minimum temperature and perceived sleep disturbance for all team members (r=0.179, n=157, P< 0.05) (Figure 2) from day 1 to day 11. This also applied to all drivers (r=0.319, n=58, P
Journal of the Royal-Society of Medicine Volume 85 June 1992
Health of
a
team competing in the 1990 World Solar Car Challenge
R G Moorhead ERCGP DCM C Laurence BA Smart Road, Modbury SA 5092, Australia
General Practice Teaching Unit, Modbury Hospital,
Keywords: solar car; Nottingham Health Profile; International Classification of Primary Care
Summary The health of a team participating in the 1990 World Solar Car Challenge was recorde for 10 of the 11 race days. Morbidity was collected during daily consultations with the team doctor and the diagnoses were later converted to the ICPC code. Team members' self-perceived health status was also recorded daily, using the Nottingham Health Profile. Team drivers consulted the doctor more often than the support staff and the three full-time drivers had significantly more diagnoses than the support staff. The Nottingham Health Profile scores on sleep, energy and emotional reactions showed correlations between higher minimum temperatures and sleep for all team members and for the three full-time drivers, there were significant correlions bet-ween increasig maximum temperatures and emotional reaction sores. The morbidity records and perceived health scores reflect the conditions ofthe race. Twenty-five per cent offull-time driver consultations dealt with skin, eyelid or finger infections probably caused by the lack of washing water. The scores on sleep and emotional reactions were affected by temperature and previous research reports degradation in concentration and dual tasks with increasing temperature. This may account for the difficulty some drivers had in continuing their shifts. Close supervision of the drivers and the recording of their perceived health status helped reduce the health problems ofthe team. Introduction The World Solar Car Challenge was held in Australia in November 1990 and attracted competitors from many countries. Solar vehicles raced 3000 kilometres from Darwin to Adelaide through harsh conditions (Figure 1). The climates encountered on the race trip were initially tropic humid savannah, dry steppe and for most of the journey dry desert. Crews had to contend with approaching and overtaking road trains (three unit semi-trailers), small tornado-like dust storms (which completely destroyed one solar car) and temperatures at road level of over 50°C. In this hot environment they planned and executed their racing tactics. High temperature has been linked to such psychological parameters as irritability, outbursts of temper, negativity of reactions to others1-3, reduced performance, social attraction and helping4. It has historically been associated with collective violence in American cities5'6. Archival data has suggested an association between ambient temperature of around 30°C and such violence. However, increments of temperature beyond this were associated with decreasing incidence of violent events and a duration of 7 days high temperature preceded violence. The ability to perform
Figure 1. The 1990 World Solar Car Challenge showing the distance travelled by the team each day
in hot environments has also attracted industrial7
and military interest8. The health of one solar car team in this race was studied and a correlation made between temperature and self perceived health. The aim of the study was to assess the perceived health of team members, record the morbidity at the doctor patient consultation on a daily basis and also to correlate members' sleep, energy and emotional scores against temperature. Method Car 18, 'Eos' had a team of 18 people, one of whom 0141-0768/92/ was an author in the capacity of medical officer. Eight 060334-04/$02.00/0 students (mean age 17 years) from an Adelaide girls i 1992 school, Annesley College, drove the vehicle for 12 The Royal days. Power of 1100 watts from the solar array via Society of lead acid batteries drove a one horse power electric Medicine
Journal of the Royal Society of Medicine Volume 85 June 1992
motor to give an average speed of 35 km/h (maximum 73) and an average distance of 270 km a day. Because of the need for lightness the vehicle carried no airconditioning. Racing rules demanded a stop every evening at 17.00 h and a morning start at 08.00 h. This left the team in non-racing time in the desert under canvas and hence created long periods of exposure to high temperature. Every team member filled out part one of the Nottingham Health Profile9 (often with the aid of a torch) each evening after eating. Sleep, energy and emotion scores from this profile were correlated with the dry bulb temperatures taken at the weather station of the Northern Territory and South Australia Bureau of Meteorology closest to the team each 24 h. The morbidity at the morning and evening surgery (conducted around the open boot of the lead vehicle of the convoy) was recorded and coded according to the International Classification of Primary Care'0.
29 26
T E m P E R A T U R E
I
x
x
x
x
x
x
r,
x
Is
lo
20
soT o S 70 S 40 SLEEP DISTURBANCE SCORE
3
o
Figure 2. All team members - sleep and temperature
x
Results The team took 12 days to complete the journey and in all but the last 2 days the maximum temperature ranged from 320C to 430C. Health data were recorded for every day except the last one. There were eight drivers (three full-time and five relief) and 10 support staff (nine full-time and one relief). The relief personnel were flown in 4-7 days after the race had started to ease the drivers' workload. Sixty-three per cent of all drivers consulted the doctor on the trip compared with 50% of the support staff (not significant). All drivers generated 26 consultations as compared with six for the support staff (not significant). The diagnoses at these consultations fitted the rubrics in the classification ICHPPC-2-Defined" and were converted to ICPC code'0 (Table 1). There were 35 diagnoses made at consultation for all drivers and eight for all support staff (not significant). Most of the consultations came from the three fulltime drivers who had the longest exposure to driving the solar car. They had 24 consultations compared with six from the nine full-time support staff and there was a significant difference (Mann-Whitney U=0, P=0.01) in whether they consulted or did not consult compared with the full-time support staff. There were 32 full-time driver diagnoses compared Table 1. Diagnoses made at doctor-patient contact
ICPC code Diagnoses A04 Tiredness D93 Irritable bowel syndrome S10 Boils L79 Sprained foot R06 Epistaxis N02 Tension headache N89 Migraine F72 Stye S17 Abrasion S18 Laceration S92 Heat rash S12 Insect bite Other
Total
x T
E
24
-
x
x
-
M
x E
na
R A U
R E Is
is
14
O
tO
2
30
40
70
s
80
I00
itO
11 0
SLEEP DISTUR13ANCE SCORE
Figure 3. All drivers sleep and temperature -
with seven support staff diagnoses from these consultations, which was significant (Mann-Whitney U=0, P=0.01). The Nottingham Health Profile generated perceived health data on sleep, emotional reactions and energy. There was a correlation between higher minimum temperature and perceived sleep disturbance for all team members (r=0.179, n=157, P< 0.05) (Figure 2) from day 1 to day 11. This also applied to all drivers (r=0.319, n=58, P
