Exercise-induced dyspnea is a problem among the general adolescent population
Rationale Respiratory symptoms during exercise are common and might limit adolescents' ability to take part in physical activity. Objective To estimate the prevalence, determinants and consequences of exercise- induced dyspnea (EID) on daily life in a general population of 12-13 year old adolescents. Methods A letter was sent to the parents of all 12–13 year old adolescents in the city of Uppsala (n=3838). Parents were asked to complete a questionnaire together with their child on EID, asthma and allergy, consequences for daily life (wheeze, day time- and nocturnal dyspnea) and physical activity.The response rate was 60% (n=2309). Results Fourteen percent (n=330) reported EID, i.e. had experienced an attack of shortness of breath that occurred after strenuous activity within the last 12 months. Female gender, ever-asthma and rhinitis were independently associated with an increased risk of EID. Ever-asthma was reported by 14.6% (n=338), and 5.4% (n=128) had both EID and ever-asthma. Sixty-one percent (n=202) of the participants with EID did not have a diagnosis of asthma. In addition to rhinitis, participants with EID reported current wheeze and day-time as well as nocturnal dyspnea more often than the group without EID. No difference was found in the level of physical activity between participants with and without EID. Conclusion Adolescents with undiagnosed exercise-induced dyspnea have respiratory symptoms and are affected in daily life but have the same level of physical activity as adolescents without exercise-induced respiratory symptoms.
Exercise-induced dyspnea is a problem
among the general adolescent population
, K. Norlander
, H. Hedenstro
, C. Janson
, L. Nordvall
, M. Emtner
Physiotherapy, Department of Neuroscience, Uppsala University, Uppsala, Sweden
Otolaryngology and Head & Neck Surgery, Department of Surgical Science, Uppsala University,
Clinical Physiology, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
Respiratory Medicine and Allergology, Department of Medical Sciences, Uppsala University, Uppsala,
Pediatrics, Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden
Received 5 November 2013; accepted 17 March 2014
Available online 27 March 2014
Rationale: Respiratory symptoms during exercise are common and might limit adolescents’
ability to take part in physical activity.
Objective: To estimate the prevalence, determinants and consequences of exercise-induced
dyspnea (EID) on daily life in a general population of 12e13 year old adolescents.
Methods: A letter was sent to the parents of all 12e13 year old adolescents in the city of Up-
psala (n Z 3838). Parents were asked to complete a questionnaire together with their child on
EID, asthma and allergy, co nsequences for daily life (wheeze, day time- and nocturnal dys-
pnea) and physical activity. The response rate was 60% (n Z 2309).
Results: F ourt een pe rcen t (n Z 330) reported EID, i.e. had experienced an attack of short-
ness of br eath that occurred after strenuous activity within the last 12 months. Female
gender, ever- asthma and rhinitis were independently assoc iated with an increased risk
of EID. Ever-asthma was reported by 14.6% (n Z 338), and 5.4% (n Z 128) had both
EID and ever-asthma. Six ty-one percent (n Z 202) of the participants with EID did not
have a diagnosis of asthma. In add ition to rhinitis, participants with EID reported current
wheeze and day-time as well as noctu rnal dyspnea more often than the group withou t
EID. No difference was found in the level of physical activity between participants with
and without EID.
* Corresponding author. Neuroscience, Physiotherapy, Uppsala University, Box 593 BMC, 751 24 Uppsala, Sweden. Tel.: þ46 18 4714767,
þ46 736 99 53 67; fax: þ46 18 51154.
E-mail address: firstname.lastname@example.org (H. Johansson).
0954-6111/ª 2014 Elsevier Ltd. All rights reserved.
Available online at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/rmed
Respiratory Medicine (2014) 108, 852e858
Conclusion: Adolescents with undiagnosed exercise-induced dyspnea have respiratory
symptoms and are affected in daily life but have the same level of physical activity as ad-
olescents without exercise-induced respiratory symptoms.
ª 2014 Elsevier Ltd. All rights reserved.
Respiratory problems in connection with physical activity
are common in adolescents. The prevalence of self-
reported exercise-wheeze in the International Study of
Asthma and Allergy in Childhood (ISAAC) among 13e14 year
old adolescents was 19% . Apart from exercise-induced
bronchoconstriction seen in asthma there are several
other disorders that may cause respiratory problems in
connection with exercise. Among these are exercise-
induced laryngeal obstruction, vocal cord dysfunction,
exercise-induced hyperventilation, chronic lung diseases
other than asthma, cardiac disease, congenital malforma-
tions and unexpectedly poor physical ﬁtness [2e7].
Exercise-induced respiratory symptoms may limit a
subject’s ability to be physically active, which may have
negative health effects as physical exercise is associated
with numerous health beneﬁts . It is not known to what
extent exercise-induced respiratory symptoms limit phys-
ical activity, but in one study investigating children 12e14
years of age, 25% of the subjects reporting undiagnosed
respiratory symptoms also reported activity limitations .
Besides activity limitations they also reported substantial
negative effects on daily life such as sleep disturbances,
absence from school and hospitalization.
The aim of this study was to estimate the prevalence,
determinants and consequences of exercise-induced dys-
pnea (EID) on daily life and physical activity in a general
population of 12e13 year old adolescents.
Materials and methods
Study design and study population
In this descriptive cross sectional study all 12e13 year old
adolescents in the city of Uppsala (n Z 3838) were invited
In December 2010, addresses for all the subjects were
collected from the Swedish Population Register. In
JanuaryeFebruary 2011 a letter was sent to adolescents
and parents with an offer to participate in the study. Par-
ents were asked to complete an online self-administered
questionnaire together with their child. A reminder was
sent to subjects who did not respond within four weeks. If
necessary a reminder together with a paper copy of the
questionnaire and an enclosed stamped, self-addressed
return envelope was sent a month later. All data were
collected from JanuaryeMay 2011. Out of the 3838 ques-
tionnaires, 23 were returned unopened due to incorrect
addresses. The response rate was 64.7% leaving a total of
2468 questionnaires for analysis. One hundred and ﬁfty-
nine subjects declared that they did not want to participate
in the study, thus the ﬁnal study population comprised 2309
subjects (1136 females) (Table 1). A total of 1399 subjects
answered the questionnaire on line and the rest (n Z 910)
ﬁlled out and returned a paper copy.
The study was approved by the Regional Ethics Com-
mittee, Uppsala (Dnr. 2011:413).
The questionnaire contained 37 questions comprising items
about EID, asthma and allergy, physical activity and back-
ground. Questions about EID, asthma and allergy were
based on the International Study of Asthma and Allergy in
Childhood Questionnaire  and the European Community
Respiratory Health Survey . Questions about level of
physical activity were based on the Health Behavior of
School-aged Adolescents (HBSC), WHO Collaborative Cross-
National Study [12,13].
Exercise-induced dyspnea (EID): “Have you had an attack of
shortness of breath that happened after strenuous activity
at any time during the last 12 months?” .
Table 1 Characteristics for the total study population
(n Z 2309) and participants with (n Z 330) and without
exercise-induced dyspnea (EID) (n Z 1979).
EID No EID p
N (%) N (%) N (%)
330 (14.3) eee
Ever-asthma 338 (14.6) 128 (38.7) 210 (10.6) <0.001
346 (15.0) 58 (17.6) 288 (15.0) 0.19
Rhinitis 399 (17.2) 100 (30.3) 299 (15.1) <0.001
274 (11.8) 158 (47.9) 116 (5.9) <0.001
73 (3.2) 42 (12.7) 31 (1.6) <0.001
160 (6.9) 81 (24.5) 79 (4.0) <0.001
p-Value: EID versus No EID.
Overweight and obesity is deﬁned as body mass index kg/m
Exercise-induced dyspnea is a problem among the adolescent population 853
Ever-asthma: Having ever been diagnosed by a physician
as having asthma.
Overweight and obesity: Body mass index kg/m
Rhinitis: “Have you ever had hay fever?”  .
Current wheeze: “Have you had wheezing or whistling in
the chest during the last 12 months?” .
Daytime dyspnea: “Have you had an attack of shortness
of breath that came on during the day when you were at
rest at any time during the last 12 months?” .
Nocturnal dyspnea: “Have you woken up with a feeling
of tightness in the chest at any time during the last
12 months?” and/or “Have you been woken by an attack
of shortness of breath at any time during the last 12
Absence from school : Having missed 10 school days the
last semester (i.e. ﬁve months period) because of infections
or symptoms of the airways.
Asthma medication: Reporting use of short acting
bronchodilators more than twice last week, and/or use of
inhaled corticosteroids the last six months and/or use of
combination of inhaled corticosteroids and long acting
bronchodilators the last six months.
Exercise-induced respiratory symptoms “Have you had
any of the following symptoms more than once during or
after physical exercise during the last 12 months; wheeze,
chest tightness, cough, throat tightness, choking sensation,
hoarseness or inspiratory stridor?”
Physical activity: “During a typical or usual week, on
how many days were you physically active for a total of at
least 60 min per day? Physical activity is deﬁned as all ac-
tivities (school activities, transport to and from school and
leisure activities) that raises your heart rate and makes you
breath hard” [12,13]. Participants that reported physical
activity on at least a moderate level 60 min per day 7 days
per week were deﬁned as being physically active according
to international guidelines regarding physical activity for
children and adolescents [16e18].
Data were analyzed using the Statistical Package for Social
Science (SPSS) software version 19 (SPSS Inc. Chicago, IL,
USA). Differences in percentage between groups were
calculated using a two-sided chi-squared test. Continuous
data were compared using two-sided unpaired t-tests. A p-
value <0.05 was considered statistically signiﬁcant. A lo-
gistic regression analysis (odds ratios (OR) and 95% conﬁ-
dence intervals (CI)) was performed with exercise-induced
dyspnea as the dependent variable and gender, ever-
asthma, rhinitis and overweight and obesity as indepen-
There was no difference regarding age, gender and postal
area codes (namely cities, towns and semi rural areas)
between responders and non-responders.
Total study population
Participant characteristics are presented in Table 1. EID
was reported by 14.3% (n Z 330), ever-asthma by 14.6%
(n Z 338) and both EID and ever-asthma by 5.4% (n Z 128)
(Fig. 1). Sixty-one percent (n Z 202) of the participants
with EID did not have asthma. Female participants reported
EID to a greater extent than males (Fig. 2). Participants
with EID reported rhinitis, current wheeze and day-time as
well as nocturnal dyspnea more often than the group
without EID. Ever-asthma (OR 5.00, CI 3.77e6.62), female
gender (OR 1.80, CI 1.40e2.33) and rhinitis (OR 1.73, CI
1.29e2.32) were independently associated with an
increased risk of EID. Overweight and obesity were not
associated with an increased risk of EID.
EID in participants without ever-asthma
Data for participants without ever-asthma are presented in
Table 2. EID was reported by 10.2%. Participants with EID
reported more rhinitis, current wheeze, day time- as well
Figure 1 Number, n (%) of participants with exercise-
induced dyspnea, exercise-induced dyspnea and ever-asthma
and only ever-asthma out of the total population n Z 2309.
Figure 2 Percentage of female and male subjects reporting
exercise-induced dyspnea in the total population (n Z 2309),
no asthma group (n Z 1971) and ever-asthma group (n Z 338).
854 H. Johansson et al.
as nocturnal dyspnea and absence from school than those
without EID. In the group with EID, more participants re-
ported use of asthma medication compared to the group
without EID (12.4% vs. 1.6% p < 0.001). No differences be-
tween groups were found regarding overweight and obesity.
EID in participants with ever-asthma
Data for participants with ever-asthma are presented in
Table 3. EID was reported by 36.9%. Participants with EID
reported more current wheeze and day-time and nocturnal
dyspnea than those without EID. More participants with EID
reported use of asthma medication than participants in the
group without EID (59.4% vs. 29% p < 0.001). There were no
differences between groups regarding overweight and
Other exercise-induced symptoms in participants
The reported occurrence of other respiratory symptoms
during or following exercise in participants with EID is
presented in Table 4. The most common symptoms were
cough, chest- and throat tightness and exercise-wheeze.
These symptoms were more commonly reported in partic-
ipants with ever-asthma than those without asthma. No
difference was found in the prevalence of chest tightness,
hoarseness and choking sensation between participants
with EID with or without ever-asthma.
On average the participants were physically active 4.1 days
per week for a total of at least 60 min per day. Only 12% of
the total population was physically active 60 min per day
seven days per week according to guidelines. A greater
proportion of the males were physically active according to
guidelines compared to females (13.9 vs. 10.7%, p Z 0.02),
and males also reported more active days per week
compared to females (4.3 vs. 4.0 days p Z 0.01). The group
of participants with EID were physically active on average
4.3 days per week compared to 4.1 days in the group
without EID (p Z 0.045). Females with EID were physically
active on average 4.3 compared to 3.9 days in females
without EID (p Z 0.006). In males, both the group with and
without EID were physically active 4.3 days per week.
Regarding the proportion of participants being physically
active according to guidelines, no difference was found,
neither between the groups with and without EID nor be-
tween groups with and without ever-asthma (Fig. 3).
In participants with EID a greater proportion of the
normal-weight participants was physically active according
to guidelines compared to the group of overweight and
obese participants (15 vs.5.2% p Z 0.046). In the subgroup
of participants with EID without ever-asthma 13.2% of the
normal-weight participants were physically active
compared to none in the group of overweight and obese
participants (p Z 0.029).
The prevalence of EID among adolescents in this study was
14%, and the prevalence was higher in girls than boys. Of
the participants reporting EID over 60% did not have an
asthma diagnosis. Non-asthmatic participants with EID re-
ported signiﬁcantly more respiratory problems and negative
consequences in daily life than adolescents without EID. No
Table 2 Characteristics of participants without ever-
asthma with (n Z 202) and without exercise-induced dys-
pnea (EID) (n Z 1769).
With EID Without EID p
N (%) N (%)
Rhinitis 44 (21.8%) 227 (12.8%) <0.001
Current wheeze 70 (34.6%) 60 (3.4%) <0.001
Day-time dyspnea 20 (9.9%) 23 (1.3%) <0.001
Nocturnal dyspnea 32 (15.8%) 57 (3.2%) <0.001
22 (10.5%) 73 (4.1%) <0.001
Table 3 Characteristics of participants with ever-asthma
with (n Z 128) and without exercise-induced dyspnea
(EID) (n Z 210).
With EID Without EID p
N (%) N (%)
Rhinitis 56 (43.8%) 72 (34.3%) 0.078
Current wheeze 88 (68.8%) 56 (26.7%) <0.001
Day-time dyspnea 22 (17.2%) 8 (3.8%) <0.001
Nocturnal dyspnea 49 (38.3%) 22 (10.5%) <0.001
20 (15.6%) 17 (8.1%) 0.083
Table 4 Exercise-induced respiratory symptoms in sub-
jects with exercise-induced dyspnea (n Z 330).
All subjects Without
N (%) N (%) N (%)
126 (38.2%) 50 (24.8%) 76 (59.4%) <0.001
130 (39.4%) 74 (36.6%) 56 (43.8%) 0.197
Cough 170 (51.5%) 89 (44.1%) 81 (63.3%) 0.001
121 (36.7%) 58 (28.7%) 63 (49.2%) <0.001
68 (20.6%) 39 (19.3%) 29 (22.7%) 0.46
Hoarse voice 87 (26.4%) 46 (22.8%) 41 (32.0%) 0.063
86 (26.1%) 39 (19.3%) 47 (36.7%) <0.001
Exercise-induced dyspnea is a problem among the adolescent population 855
difference was found in the level of physical activity be-
tween participants with and without EID.
We found that more than 60% of the adolescents with EID
had never had a physician diagnosis of asthma. This group
reported rhinitis, current wheeze and day-time as well as
nocturnal dyspnea more often than the non-asthmatic ad-
olescents without EID. They also reported more absence
from school. Yeatts et al.  investigated health conse-
quences associated with undiagnosed breathing problems
(i.e. wheezing) among adolescents. As in our study, the
participants with undiagnosed respiratory problems re-
ported more absence from school compared to healthy
peers. In addition, previous studies have shown that sub-
jects with undiagnosed breathing problems have low
health-related quality of life [19,20].
Among participants without asthma, female adolescents
had a higher prevalence of EID than males; the male to
female ratio was 0.7. Other studies have conﬁrmed the
association between female gender and undiagnosed
breathing problems [9,21]. Female athletes report physical
symptoms, such as shortness of breath, nearly twice as
often as their male counterparts in another study .
Only 12% of the participants reported being physically
active according to international guidelines (i.e. 60 min
per day seven days per week). Experiencing EID did not
seem to affect the level of physical activity according
to guidelines, as no difference was found between adoles-
cents with and without EID. In fact the group with EID re-
ported more active days per week compared to
those without EID. In agreement with Berntsen et al. 
we found that adolescents with asthma were as active
as those without. The same has also been shown to be
true in a recent study comparing adults with and without
Among participants with EID the overweight and obese
adolescents were less physically active compared to
normal-weight subjects. The relation between weight and
physical activity has been reported by others .
There are several plausible explanations as to why EID is
common among participants without an asthma diagnosis in
our study. Exercise-induced bronchoconstriction as a
manifestation of asthma is a widely studied cause of EID
and some of the participants in our study probably have
undiagnosed asthma. This might be reﬂected in the higher
prevalence of asthma related symptoms, allergic rhinitis,
and the use of asthma medication in the group of partici-
pants with EID without ever-asthma than in the non-
asthmatic, non EID group. However, De Baets et al. ,
after performing exercise tests on a large number of chil-
dren, reported that respiratory symptoms such as dyspnea
and exercise-wheeze were poor predictors of exercise-
Exercise-induced dyspnea in otherwise healthy adoles-
cents may have causes other than asthma [6,26e29].
Exercise-induced laryngeal obstruction has been reported
to produce symptoms similar to exercise-induced bron-
choconstriction . In a study by Christensen et al. ,
the prevalence of exercise-induced laryngeal obstruction
was 7.5% in a randomly selected sample 14e24 years of age.
In addition, exercise-induced hyperventilation, chronic
lung diseases other than asthma, cardiac disease and
congenital malformations may all result in dyspnea during
physical exertion [4,7]. Some adolescents may also inter-
pret dyspnea associated with normal physiologic limitation
consistent with their physical ﬁtness level as abnormal
In our study exercise-wheeze was more common in the
asthmatic than the non-asthmatic group with EID, while
other symptoms such as chest tightness, hoarse voice and a
sensation of choking had a relatively similar prevalence in
both groups. Dyspnea, hoarse voice and cough have previ-
ously been reported as the most common symptoms among
subjects with laryngeal symptoms when exercising .On
the other hand Christensen et al. , found no difference
between subjects with exercise-induced laryngeal
obstruction compared to subjects with airway hyper-
responsiveness. Thus, it remains to be further investi-
gated whether using a panel of questions on exercise-
induced symptoms is useful when trying to distinguish EID
that is related to asthma from that which is not.
The strengths of the present study are its large size and
the use of data from a population sample. Respiratory
questions used in our questionnaire have also been used in
many previous studies and are validated [11,31]. The study
also has limitations such as being a cross-sectional study
and therefore it cannot establish a cause-and-effect rela-
tionship. The questionnaire return rate of 60% can have
inﬂuenced the results. While there were no differences
regarding age, gender and postal area codes between re-
sponders and non-responders nothing is known about the
prevalence of asthma, EID or other symptoms among non-
responders. This can potentially lead to a non-responder
rate bias. The information on physical activity is self-
reported, and these results must therefore be interpreted
with caution. Substantial discrepancies between self-
reported instruments and objective measures (i.e. activity
Figure 3 Proportion (%) of subjects with and without
exercise-induced dyspnea (EID) and ever-asthma who were
physically active on at least a moderate level 60 min per day
7 days per week according to international guidelines regarding
physical activity for children and adolescents No asthma with
EID: n Z 202, without EID: n Z 1769. Ever-asthma with EID:
n Z 128, without EID: n Z 210.
856 H. Johansson et al.
meters) have been reported  and self-report in-
struments tend to overestimate the intensity and duration
of physical activity .
In conclusion, exercise-induced dyspnea in adolescents
without asthma is not uncommon and more females than
males are affected. Compared to healthy peers these ad-
olescents have more negative effects on daily life such as
absence from school and nocturnal dyspnea whereas no
difference in physical activity was found. The reasons
behind the exercise-induced dyspnea experienced by a high
number of non-asthmatic adolescents warrant further
HJ; designed study, collected data, analyzed data, wrote
paper. KN; designed study, collected data, analyzed data,
wrote paper. HH; designed study, analyzed data, wrote
paper. CJ; designed study, analyzed data, wrote paper. LN;
designed study, analyzed data, wrote paper. LN designed
study, analyzed data, wrote paper. ME; designed study,
analyzed data, wrote paper.
Conﬂict of interest
There are no competing or conﬂicts of interests.
None of the authors have a declared conﬂict of interest.
The study sponsors have no involvement in study design,
collection, analysis and interpretation of data, in the
writing or in the decision to submit the manuscript.
The authors thank the participating adolescents and their
The authors are grateful for the help from research
administrator Gun-Marie Bodman Lund, Department of
Medical Sciences, Respiratory Medicine and Allergology,
The study was supported by the Signhild Engqvist Foun-
dation, the Bror Hjerpstedt Foundation and the Swedish
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