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GordonL, etal. Br J Sports Med 2017;51:1295–1300. doi:10.1136/bjsports-2016-096964
ABSTRACT
Aim There are limited data on the negative effects
of exercise in athletes with acute infective illness. The
aim of this study was to determine whether a recently
diagnosed prerace acute illness in runners affects the
ability to finish a race.
Methods Runners were prospectively evaluated in the
3 days before the race for acute infective illness and then
received participation advice using clinical criteria based
on systemic or localised symptoms/signs. We compared
the did-not-start and the did-not-finish frequencies of
ill runners (Ill=172: localised=58.7%; systemic=41.3%)
with that of a control group of runners (Con=53 734).
Results Runners with a systemic illness were 10.4%
more likely not to start compared with controls (29.6%
vs 19.2%) (p=0.0073). The risk difference of not starting
the race in runners who were advised not to run the
race compared with controls was 37.3% (56.5% vs
19.2%, p<0.0001). Compared with controls, runners
with illness had a significantly (p<0.05) greater risk (any
illness (5.2% vs 1.6%), systemic illness (8.0% vs 1.6%),
illness <24 hours before the race (11.1% vs 1.6%))
and relative risk (prevalence risk ratio) (any illness=3.4,
systemic illness=4.9, systemic illness <24 hours before
the race=7.0) of not finishing the race.
Conclusions Runners with prerace acute systemic
illness, and particularly those diagnosed <24 hours
before race day, are less likely to finish the race,
indicating a reduction in race performance.
INTRODUCTION
Is it safe for an athlete with recent or current symp-
toms of an acute illness to train or compete? This
remains a challenging clinical decision for any Sport
and Exercise Medicine (SEM) physician. There are
only a small number of studies with evidence-based
return-to-play (RTP) guidelines to assist SEM physi-
cians in providing safe participation advice to an
athlete with an acute illness.1 2 This is surprising,
given that there are many studies showing that acute
illness, particularly respiratory tract (RT) illness,
is the most common reason for medical consul-
tations in SEM clinics,3 as well as in tournament
settings.4–14 RT symptoms may not always be due
to an infection and it is important to consider other
factors such as allergy.15–19 Risk factors for acute
illness, particularly RT illness in athletes, include
training load,19–23 environment,5 travel to a distant
country23 24 and allergy.15 25 26
The current RTP guidelines for athletes with
acute RT illness are an adaptation of a clinical
tool known as the ‘neck check,’ which was first
proposed in 199327 and subsequently adapted by
others.28–31 This tool is based on localised (above
the neck) versus systemic (below the neck) symp-
toms and signs, but limited research data support
its use.1 2 In particular, we are not aware of any
data where localised or systemic symptoms of acute
illness affect exercise performance. We showed in a
recent study that runners with self-reported symp-
toms of prerace acute illness, who started a race,
had a higher did-not-finish (DNS) frequency (2.1%)
compared with controls (1.3%) (p=0.0346), partic-
ularly runners with systemic symptoms (2.4%;
risk ratio=1.90).32 However, in this, and other
previous studies,15 20 32 33 the diagnosis of pre-event
acute illness was based on self-reported symptoms
only.
The aims of this study were to (1) document
the type of acute illness in runners presenting to a
Pre-Race acute Illness Medical Assessment (PRIMA)
facility in the 3 days before a race; (2) determine if
runners with acute illness advised to not start the
race, did start; and (3) determine if runners with
acute illness, who decided to start the race, finished
the race.
METHODS
Type of study
This was a prospective cohort study.
Study participants
All the runners who registered for the 56 km or
the 21.1 km races in the 2013 and/or the 2014
Old Mutual Two Oceans Marathon in Cape
Town, South Africa (n=53 976) were considered
as possible study participants. Runners who were
concerned about symptoms of acute illness in the 3
days before the race had the opportunity of a free
medical assessment at a PRIMA facility—part of the
‘Medical Village’ at the compulsory prerace regis-
tration venue. We advertised the PRIMA facility
in educational health emails sent out to all regis-
tered runners in the 3 months before the race, as
well as on the event website and magazine. In 2013,
a prerace email invited runners concerned about
acute illness to the medical facility before the race,
and in 2014 runners also received text messages
6 and 4 days before the race. The main sponsor’s
stall, providing complimentary wellness checks
(including blood pressure, cholesterol and glucose),
referred several runners with symptoms of acute
illness to the PRIMA medical facility. The PRIMA
Recent acute prerace systemic illness in runners
increases the risk of not finishing the race: SAFER
studyV
Leigh Gordon,1 Martin Schwellnus,2,3 Sonja Swanevelder,4 Esme Jordaan,4
Wayne Derman5
Original article
To cite: GordonL,
SchwellnusM, SwanevelderS,
etal. Br J Sports Med
2017;51:1295–1300.
►Additional material is
published online only. To view
please visit the journal online
(http:// dx. doi. org/ 10. 1136/
bjsports- 2016- 096964).
1Department of Human Biology,
UCT Research Unit for Exercise
Science and Sports Medicine,
Faculty of Health Sciences,
University of Cape Town, Cape
Town, South Africa
2Sport, Exercise Medicine and
Lifestyle Institute (SEMLI),
University of Pretoria, Faculty of
Health Sciences, Pretoria, South
Africa
3IOC Research Centre, Pretoria,
South Africa
4Biostatistics Unit, Medical
Research Council, Parow, South
Africa
5Institute of Sport and Exercise
Medicine, Stellenbosch
University, Stellenbosch, South
Africa
Correspondence to
Professor Martin Schwellnus,
Institute for Sport, Exercise
Medicine and Lifestyle Research,
University of Pretoria, Faculty
of Health Sciences, South
Street, Sports Campus, Hatfield,
Pretoria 0028, South Africa;
mschwell@ iafrica. com
Accepted 10 March 2017
Published Online First
12April2017
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Original article
facility was open for the duration of the Registration Expo in the
3 days prior to the race.
PRIMA: history and examination
We recorded all the data, including demographic informa-
tion (name, gender and unique race number) and the race for
which they were registered, on electronic tablets (Galaxy Tab
2 V.10.1; Samsung, Korea). PRIMA staff (SEM physicians in
2013 and either nurses or SEM physicians in 2014) obtained
a medical history, referring runners with any one (or more)
of the following symptoms of an acute illness for a physical
examination:
►any systemic symptoms of infection: fever, myalgia,
general body aches, excessive fatigue, malaise, arthralgia or
headaches;
►any lower RT symptoms of infection: productive or non-
productive cough, wheezing, ‘tight’ chest, chest pain or
shortness of breath;
►gastrointestinal symptoms: abdominal pain, cramps, nausea,
vomiting or diarrhoea;
►any symptoms suggestive of cardiac disease: chest pain,
shortness of breath or palpitations;
►a sore throat;
►any runners requesting a physical examination.
A SEM physician conducted the general and specific phys-
ical examination in a private cubicle after informed consent
by the runner. A nurse (in 2014) recorded vital sign investiga-
tions: tympanic thermometry (Braun Thermoscan, IRT 4520),
resting blood pressure and resting heart rate. The SEM physi-
cian conducted a general and specific systemic examination
of the following systems: ear, nose and throat; respiratory,
cardiac, abdominal, neurological or musculoskeletal systems. We
recorded and securely stored all clinical data, including the final
working diagnosis and secondary diagnoses.
Diagnostic groups
Two clinicians assessed the clinical data of all runners with any
upper or lower RT symptoms, gastrointestinal symptoms or
systemic symptoms of illness (fever, fatigue, malaise, myalgia,
arthralgia, general body aches, headaches) to identify possible
acute infection. Tympanic temperature and heart rate were
considered in cases where the diagnosis of an infection was
unclear. We considered a tympanic temperature ≥37.5°C in
men, and ≥37.1°C in women to be above normal,34 and we used
a resting HR of >75 beats/min as an indicator of possible infec-
tion, in the context of appropriate symptoms and clinical signs.
A sinus bradycardia (<60 beats/min) is seen in up to 80% of
trained endurance athletes35 and the resting HR can increase by
10–15 beats/min with infection.36
We assigned diagnostic codes to categorise illness in runners
as localised or systemic as follows. We defined a localised illness
as either a localised upper respiratory tract illness (URTI) that
included rhinitis (infected or not infected), pharyngitis, laryn-
gitis, sinusitis (congestion) or any other localised illness. In the
absence of an exudate or any systemic features, we classified
cervical lymphadenopathy with localised throat erythema as
a localised pharyngitis. In cases where clinicians recorded two
diagnoses of localised illness in a runner, we categorised the
illness as a localised illness.
We defined systemic infective illness as an URTI with systemic
features, other systemic infective illness (mostly ‘influenza’-like
illnesses), suspected myopericarditis, lower respiratory tract
illness (LRTI) and gastroenteritis. In the case where a runner
presented with symptoms and signs of both a ‘localised’ illness
and a systemic illness, we categorised the illness as systemic.
Advice given to runners reporting to the PRIMA facility
On completion of the medical assessment at the PRIMA facility,
medical staff gave runners advice regarding participation on race
day. In the illness group, we based advice on the current RTP
clinical guidelines using the differentiation between a localised
illness and a systemic illness (see online supplementary table 1).
Race day data: race starting and finishing
We tracked all runners during race day with an electronic ‘Cham-
pion-chip’ attached to one of the runner’s shoes. The runners
crossed mats at the starting line, along the route and at the finish
line, allowing the chip data to be identified and recorded. We
categorised runners as ‘non-starters’ (DNS; did-not-start) if any
of the course mats (at the start, on the course or at the finish)
captured no data, and ‘non-finishers’ if the mat at the finish line
captured no data.
Main measures of outcome
►the prevalence (%) of runners with symptoms, a clinical
diagnosis and the diagnostic category (localised vs systemic)
of runners in the illness group;
►the frequency (%) of runners who were given advice not to
run;
►the absolute and relative risk of runners with illness not
starting the race (DNS);
►the absolute and relative risk of runners with illness not
finishing the race (DNF).
Research ethics and informed consent
Research ethics approval for this study was obtained from the
Research Ethics Committee of the Faculty of Health Sciences of
the University of Cape Town prior to starting the study (REC:
441/2012). The Research Ethics Committee of the Faculty of
Health Science at the University of Pretoria (433/2015) also
approved the study.
Statistical analysis of data
We used a Poisson regression model using a robust error esti-
mator (log link function) to analyse each individual symptom
group and subgroups. This cohort consists of correlated data,
which we accounted for by using an unstructured correlation
matrix. We estimated the prevalence risk ratio (PRR), risk differ-
ence (RD) and 95% CI by a modified Poisson regression using
robust error variances and considered p values of <0.05 as
statistically significant. In addition, we report both absolute risk
(%) and RD (% difference) between groups.
RESULTS
Demographics of the study population
We assessed a total of 242 runners in the 2 years of the study
and excluded 70 runners diagnosed with a non-infective illness.
Therefore, a total of 172 runners had symptoms and signs sugges-
tive of acute infective illness and this comprised the illness study
cohort (0.3% of all race registrants). The remaining runners who
did respond to the PRIMA facility at registration (n=53 734)
were the control group of runners for this study. We compared
outcome variables for the illness group (main cohort) and that of
the control group.
The sex distribution in the illness group was similar to that
of the control group in both the 56 km and the 21.1 km races.
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Of the 66 runners in the 56 km illness cohort, 52 (78.8%) were
male and 14 were female (21.2%). Of the 21 343 runners in the
control group that registered for the 56 km race, 15 508 (72.7%)
were male and 5835 (27.3%) were female. Among the 106
runners in the 21.1 km illness cohort, 48 (45.3%) were male and
58 (54.7%) were female. Of the 32 391 runners in the control
group that registered for the 21.1 km race, 15 932 (49.2%) were
male and 16 459 (50.8%) were female.
Prevalence of symptoms, clinical diagnosis and diagnostic
category (localised vs systemic) of runners in the illness
group
Some of the 172 runners in the illness group reported up to
eight symptoms. Sinus congestion (40.1%) followed by cough
(38.4%, and divided evenly between productive and non-pro-
ductive types), sore throat (37.8%), runny nose (25.6%), fever
(13.4%) and fatigue (12.8%) were the most common symptoms
(suffered by >10% of runners in the illness group).
We based the final diagnosis on clinical assessment, and 11
runners were assessed by medical history only, while 161 were
assessed by medical history and physical examination. Of the
172 runners in the illness group, 101 (58.7%) had a localised
illness and 71 (41.3%) a systemic illness (table 1).
The proportions of runners in the illness subgroups varied
on the different days that runners were evaluated before the
race. Almost half (49.4%) of runners with illness (85 of the 172
runners with illness) were evaluated in the 24 hours before the
race started, during which the largest proportion of runners with
systemic illness was seen (46.5%) (33 of the 71 runners with
systemic illness).
Advice given to runners with acute illness
We provided educational information to 143 of the 172 runners
(83.1%) of the illness group, and 11 runners that we assessed
after a medical history only were in this group. We advised 23
runners (13.4%) with a suspected systemic illness not to run,
based on a clinical diagnosis (medical history and physical exam-
ination). Of these runners, 12 had a LRTI, 6 a generalised URTI,
4 a systemic illness and in 1, we suspected a myopericarditis.
Absolute and relative risk of not starting the race
Absolute and relative risk of not starting the race in all runners
Of all the 53 976 runners who registered for the race in 2013
and 2014, a total of 10 358 (19.2 %) did not start the race. In
the control group of 53 734 runners, 10 309 were non-starters
(19.2%). Within the illness group of 172 runners, 38 did not
start (22.1%). Runners in the illness group did not have a signifi-
cantly higher absolute risk (RD=−3.5%, 95% CI –9.7 to 2.7)
(p=0.2630) or relative risk (PRR=1.16, 95% CI 0.89 to 1.52)
(p=0.2693) of not starting the race (adjusted for the demo-
graphic variables of year of race, gender and race type (21.1 km
vs 56 km)).
Absolute and relative risk of not starting the race in the control and
illness groups and the illness subgroups based on advice given
The DNS frequencies, PRR and RD (adjusted for the demo-
graphic variables of year of race, gender and race type (21.1 km
vs 56 km)) in the control group and the illness group, based on
advice given, are depicted in table 2.
Within the illness group, 13 of the 23 runners (56.5%) who
were advised not to run did not start the race. The absolute
and relative risk of not starting the race was not different in
the subgroup of runners who received information only or
other advice, compared with the control group. However, the
absolute risk (PRR=3.1, 95% CI 2.2 to 4.3; p<0.0001) and
relative risk (RD=40.0%, 95% CI 19.7 to 60.3; p=0.0001) of
not starting the race were significantly higher in the subgroup
of runners who were advised not to run, compared with the
control group. With respect to athlete compliance, these data
indicate that 43.5% of runners in this group were non-adherent
to advice.
Table 1 The final clinical diagnosis in the illness group (n=172)
Clinical diagnosis n
% of
illness
group
Localised illness
(n=101)
Localised URTI All localised URTI 99 57.6
Sinusitis 36 20.9
Pharyngitis 30 17.4
Rhinitis (non-infective) 28 16.3
Laryngitis 3 1.7
Rhinitis (infective) 2 1.2
Other localised infective illness 2 1.2
Systemic illness
(n=71)
URTI with systemic symptoms 39 22.7
LRTI 18 10.5
Infective gastroenteritis 9 5.2
Other systemic infective illness 4 2.3
Suspected myopericarditis 1 0.6
LRTI,lower respiratory tract illness; URTI, upper respiratory tract illness.
Table 2 TheDNS frequencies, RD and PRR in the control and illness groups, based on advice given
Starters DNS RD (%) versus control* p Value†
PRR versus control‡
(95% CI) pValue§
N % N % %
Control group (n=53,734) 43425 80.8 10309 19.2 —
Illness group (n=172) 134 77.9 38 22.1 −3.5 (−9.5to2.7) 0.2630 1.16 (0.89 to 1.52) 0.2693
Information (n=143) 119 83.2 24 16.8 −1.9 (−8.1to4.3) 0.5493 0.88 (0.62 to 1.25) 0.4679
Advised not to run (n=23) 10 43.5 13 56.5 40.0 (19.7–60.3) 0.0001 3.07 (2.18 to 4.32) <0.0001
Other advice (n=6) 5 83.3 1 16.7 — — 0.94 (0.19 to 4.54) 0.9387
*RD—adjusted for demographic variables: year of race, race type (21.1 km and 56 km), gender.
†pvalue: pairwise versus control group for RD.
‡PRR—adjusted for demographic variables: year of race, race type (21.1 km and 56 km),gender.
§pValue: pairwise versus control group for PRR.
DNS, did-not-start; PRR, prevalence risk ratio; RD, risk difference.
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Absolute and relative risk of not starting the race in the control and
illness subgroups with either localised or systemic illness
Of the 172 runners in the illness group, 101 (58.7%) had
a localised illness and 71 (41.3%) had a systemic illness. The
absolute risk (RD) and relative risk (PRR) (adjusted for year
of race, race type and gender) of not starting the race in the
subgroup of runners with localised illness and systemic illness
reported >24 hours before the race were not different from that
in the control group (table 3).
The absolute and relative risk of not starting the race was
significantly higher in the subgroup of runners with systemic
illness, compared with the control group. Similarly, compared
with the control group, the absolute risk and relative risk of not
starting the race were significantly higher in the subgroup of
runners who reported systemic illness <24 hours before the race.
However, these data should be interpreted with some caution as
the numbers of non-starters in these subgroups were small.
Absolute and relative risk of not finishing the race
The DNF frequencies and PRR (adjusted for year of race,
race type and gender) in the control group, illness group and
subgroups of the illness group (localised or systemic illness) are
depicted in table 4. The absolute risk could not be calculated due
to small numbers of non-finishers and non-convergence.
In the 84 starters who had localised illness, 3 did not finish
(3.6%), 2 of whom were evaluated the day before the race. In
the 50 runners who started the race despite having a systemic
illness, 4 did not finish (8.0%). Two of these non-finishers were
among the 32 runners who were evaluated >24 hours before the
race (6.3%) and the remaining 2 non-finishers were among the
18 runners evaluated within 24 hours of the race start (11.1%).
The absolute risk (unadjusted DNF) (% runners) of not
finishing the race was 1.6% in the control group and 5.2% in the
illness group. In the systemic illness group, 8.0% of runners did
not finish the race, and this was 6.3% and 11.1%, respectively,
for runners with systemic symptoms >24 hours, and <24 hours
before the race. As a result of the small sample size in the illness
subgroups, the adjusted absolute risk (RD) for the DNF groups
could not be obtained.
The relative risk (PRR) of not finishing the race in the
subgroup of runners with localised illness was not different
from that in the control group, but was significantly higher in
the illness group and subgroup of runners with systemic illness
compared with the control group. Similarly, compared with the
control group, the relative risk of not finishing the race was
significantly higher in the subgroup of runners who reported
systemic illness >24 hours and <24 hours before the race. These
data should be interpreted with some caution as the numbers of
runners in these subgroups were small.
DISCUSSION
This study investigated the race outcomes (DNS, DNF) based
on diagnosis and adherence to advice given by healthcare prac-
titioners of runners presenting with acute illness in the 3 days
before an endurance race (21.1 km and 56 km). Our main find-
ings were: (1) 43.5% of the runners in the illness group were
non-adherent to advice given and started the race—including
29.6% of runners with systemic illness; (2) runners with
Table 3 The DNS frequencies, RD and PRR in the control and illness groups (and subgroups of localised vs systemic illness) diagnosed in two time
periods before the race
Starters DNS RD (%) versus control* p Value†
PRR versus control‡
(95% CI) pValue§
N % % % %
Control group (n=53,734) 43425 80.8 10309 19.2
Illness group (n=172) 134 77.9 38 22.1 −3.5 (−9.5to2.7) 0.2630 1.16 (0.89 to 1.52) 0.2693
Localised illness (n=101) 84 83.2 17 16.8 −2.0 (−9.4to5.4) 0.6046 0.87 (0.57 to 1.33) 0.5265
Systemic illness (n=71) 50 70.4 21 29.6 11.6 (1.1–22.2) 0.0309 1.59 (1.13 to 2.23) 0.0073
>24 hours before race (n=38) 32 84.2 6 15.8 −1.6 (−13.6to10.5) 0.8005 0.89 (0.46 to 1.74) 0.7403
<24 hours before race (n=33) 18 54.5 15 45.5 27.1 (10.4–43.8) 0.0015 2.38 (1.67 to 3.41) <0.0001
*RD—adjusted for demographic variables: year of race, race type (21.1 km and 56 km), gender.
†pValue: pairwise versus control group for RD.
‡PRR—adjusted for demographic variables: year of race, race type (21.1 km and 56 km), gender.
§pValue: pairwise versus control group for PRR.
DNS, did-not-start; PRR, prevalence risk ratio; RD, risk difference.
Table 4 TheDNF frequencies and PRR in the control and illness groups (and subgroups of localised vs systemic illness) diagnosed in two time
periods before the race
Starters
Finishers DNF
PRR versus control*
(95% CI) pValue†
N % N %
Control group (n=43,425) 42,750 98.4 675 1.6
Illness group (n=134) 127 94.8 7 5.2 3.40 (1.76 to 6.58) 0.0003
Localised illness (n=84) 81 96.4 3 3.6 2.45 (0.85 to 7.07) 0.0986
Systemic illness (n=50) 46 92.0 4 8.0 4.87 (2.20 to 10.75) <0.0001
>24 hours before race (n=32) 30 93.7 2 6.3 3.73 (1.20 to 11.65) 0.0233
<24 hours before race (n=18) 16 88.9 2 11.1 7.03 (2.37 to 20.83) 0.0004
*PRR —adjusted for demographic variables: year of race, race type (21.1 km and 56 km), gender.
†pValue: pairwise versus control group for PRR.
DNF, did-not-finish; PRR, prevalence risk ratio.
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localised illness started and finished the race in a similar propor-
tion to control runners; and (3) runners in the illness group had
a significantly higher risk of not finishing the race, and this was
highest in runners with systemic illness in the 24 hours preceding
the race start. This last finding needs to be interpreted with some
caution because of the small numbers.
In our study, the DNS frequency for the total race popula-
tion (19.2%) is lower than that previously reported in the
literature,37 38 but higher than our more recently reported
DNS frequency of 6.6%.32 We educated runners on the impor-
tance of monitoring symptoms as these could change over time
(particularly those that we saw >24 hours before the race). We
emphasised that runners can make an informed decision about
their fitness to compete on race day, based on their symptoms.
In our illness group, we used the frequency of not starting the
race as a measure of ‘adherence to advice’ given to the runners.
We do acknowledge that acute illness may not have been the
only reason for not starting the race and that a number of other
factors could affect the decision to start the race.
In our study, 43.5% of runners with acute illness were non-ad-
herent to our advice and started the race. Runners with systemic
illness were significantly less likely to start than runners in the
control group, or runners with localised illness. This difference
was even larger in runners we evaluated <24 hours before the
race, and we attribute this to the minimal time for improve-
ment of their clinical condition. Of interest was that some of
the 56 km runners we advised against running expressed a wish
to participate in the 21.1 km race instead, perceiving it as less
‘risky.’ This is in keeping with the observations reported during
the Aberdeen marathon, where a third of the ‘drop-out’ respon-
dents indicated they would have entered a half marathon if given
the option.38 Finally, we are not aware of any data exploring the
concept of adherence to advice by athletes who have evidence of
acute illness, and we suggest that further research be conducted
to explore this area.
In this study, not finishing the race is used as a proxy for the
impact of an acute illness on race performance. Our results show
that 3.6% of runners with localised illness did not finish the race
compared with 1.6% in the control group, and these data are
similar to the 1.9% runners with self-reported prerace local-
ised symptoms that we reported from our recently published
data.32 These two studies are, to the best of our knowledge,
the first clinical data from prospective studies to indicate that
the RTP criteria, if only localised symptoms and signs present,
are a useful and valid clinical tool to advise athletes with acute
illness on RTP. However, we encourage further research in this
area, particularly with more specific diagnoses and larger sample
sizes, and more accurate measures of performance (eg, split and
finishing times compared with previous or personal best running
times).
However, we also show that, compared with runners in the
control group, 5.2% of runners in the illness group, and 8% of
runners in the systemic illness group, did not finish the race (rela-
tive risks of 3.4 and 4.9, respectively). These findings are also
similar to the DNF frequencies we recently reported for runners
with any self-reported illness (2.1%) and self-reported systemic
symptoms (2.4%).32 However, a novel finding in this study was
that 11.1% of runners with clinically diagnosed systemic illness
in the 24 hours period just before the race did not finish the
race (relative risk of 7.03 higher than control; p=0.0004). This
finding has important clinical implications and suggests that
recent clinically diagnosed systemic illness (<24 hours before
exercise) significantly affects exercise performance. However, it
is important to note that these findings should be interpreted
with some caution due to the small numbers of participants in
these subgroups, and further studies with larger sample sizes are
needed.
Our study also has several limitations including: (1) runners
who presented to the PRIMA facility were self-selected; (2) the
prevalence of acute illness in the entire race population is not
known; (3) reasons for not starting or finishing are not known;
and (4) the sample sizes in subgroups of runners are too small
to conduct a detailed analysis. We suggest further investigations
to determine whether there is a link between acute illness and
medical complications during exercise.
CONCLUSION
Among runners with a clinically diagnosed prerace acute infec-
tive illness, symptoms are mostly localised to the upper RT, but
a significant number of runners have an URTI with generalised
symptoms. Of the runners with acute illness who were advised
not to run, 43.5% ran anyway. In runners with illness, and
subgroups of runners with systemic illness or systemic illness
less than 24 hours before the race, who ran anyway, the risk of
not finishing the race was 3.6%, 8.0% and 11.1%, respectively,
compared with controls (1.6%). Therefore, runners with systemic
illness, and particularly those diagnosed <24 hours before race
day, were less likely to finish the race, indicating a reduction
in race performance. These data are important to improve the
medical care of runners (and other athletes) presenting with
acute illness before training and competition.
What are the findings?
►43.5% of runners with an acute infective illness, clinically
diagnosed in the 3 days before a race, were non-adherent to
advice not to run the race.
►Runners with systemic illness who elected to start the race
despite being advised not to had an 8% chance of not
finishing the race, compared with runners in the control
group of 1.6% (relative risk of 4.9).
►If diagnosed with an acute systemic illness within
24 hours of the race, 11.1% of runners do not finish the
race compared with 1.6% of runners in the control group
(relative risk of 7.0).
How might itimpact on clinical practice in the future?
►Sport and Exercise Medicine physicians can expect that only
about 50% of recently diagnosed acutely ill runners will
adhere to advice about not participating in a race.
►Runners with systemic symptoms and signs of acute prerace
illness have an increased risk of not completing the race—
more so if systemic symptoms and signs are present in the
24 hours before a race.
Acknowledgements The authors would like to thank the Two Oceans
organising committee for permission to conduct the research study, the athletes for
participating in the study and Dr Jill Borresen for edits and preparation of the final
manuscript.
Contributors LG: study planning, data collection, data interpretation,
manuscript drafting and editing. MS: responsible for the overall content as
guarantor, study concept, study planning, data collection, data interpretation,
manuscript (first draft), manuscript editing, facilitating funding. WD: study
planning, data collection, data interpretation, manuscript editing. SS: study
planning, data analysis including statistical analysis, data interpretation,
manuscript editing. EJ: study planning, data analysis including statistical analysis,
data interpretation, manuscript editing.
group.bmj.com on August 22, 2017 - Published by http://bjsm.bmj.com/Downloaded from
6 of 6 GordonL, etal. Br J Sports Med 2017;51:1295–1300. doi:10.1136/bjsports-2016-096964
Original article
Competing interests None declared.
Patient consent Obtained.
Ethics approval Research Ethics Committee of the Faculty of Health Sciences
of the University of Cape Town prior to starting the study (REC: 441/2012). The
Research Ethics Committee of the Faculty of Health Science at the University of
Pretoria (433/2015) also approved the study.
Provenance and peer review Not commissioned; externally peer reviewed.
© Article author(s) (or their employer(s) unless otherwise stated in the text of the
article) 2017. All rights reserved. No commercial use is permitted unless otherwise
expressly granted.
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race: SAFER study V therunners increases the risk of not finishing
Recent acute prerace systemic illness in
and Wayne Derman
Leigh Gordon, Martin Schwellnus, Sonja Swanevelder, Esme Jordaan
doi: 10.1136/bjsports-2016-096964
2017 2017 51: 1295-1300 originally published online April 12,Br J Sports Med
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