Inspiratory muscular weakness is most evident in chronic stroke survivors with lower walking speeds

Abstract

Background:
Respiratory muscular weakness and associated changes in thoracoabdominal motion have been poorly studied in stroke subjects, since the individuals' functional levels were not previously considered in the investigations.

Aim:
To investigate the breathing patterns, thoracoabdominal motion, and respiratory muscular strength in chronic stroke subjects, who were stratified into two groups, according to their walking speeds.

Design:
Cross-sectional, observational study.

Setting:
University laboratory.

Population:
Eighty-nine community-dwelling chronic stroke subjects

Methods:
The subjects, according to their gait speeds, were stratified into community (gait speed ≥0.8 m/s) and non-community ambulators (gait speed <0.8 m/s). Variables related to pulmonary function, breathing patterns, and thoracoabdominal motions were assessed. Measures of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were obtained and were compared with the reference values for the Brazilian population. The MIP and MEP values were expressed as percentages of the predicted values. Mann-Whitney-U or independent Student t-tests were employed to compare the differences between the two groups for the selected variables.

Results:
No significant between-group differences were found for the variables related to the breathing patterns and thoracoabdominal motions (0.01 < z/t < 1.51; 0.14<P<0.99). Compared to the predicted values, the stroke subjects demonstrated decreases of 26.5 and 20% of the MIP and MEP, respectively. Non-community ambulators showed significant lower predicted MIP values than those from the community ambulators (t=2.10; P=0.04). However, no significant between-group differences were found for the predicted MEP measures (t = -1.10; P=0.25).

Conclusion:
Stroke subjects demonstrated weakness of the respiratory muscles and lower predicted MIP values were found for the non-community ambulators.

Clinical rehabilitation impact:
Evaluations and interventions involving respiratory muscular training could be included in stroke rehabilitation, especially for individuals with lower functional levels.

Full text

Vol. 50 - 2014 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE 1
Inspiratory muscular weakness is most evident in
chronic stroke survivors with lower walking speeds
ambulators (t=2.10; P=0.04). However, no signicant
between-group differences were found for the predict-
ed MEP measures (t=-1.10; P=0.25).
Conclusion. Stroke subjects demonstrated weakness
of the respiratory muscles and lower predicted MIP
values were found for the non-community ambulators.
Clinical rehabilitation impact. Evaluations and in-
terventions involving respiratory muscular training
could be included in stroke rehabilitation, especially
for individuals with lower functional levels.
Key words: Stroke - Hemiplegia - Respiratory muscles -
Muscular weakness.
Stroke is considered a public health problem,
because it is the third highest leading cause of
chronic disability and one of the most devastating
neurological conditions, which lead to serious dis-
abilities.1, 2 Among the most frequently observed
decits in post-stroke individuals, muscular weak-
ness stands out, which was also observed in the re-
1UniversidadeFederaldeMinasGerais
BeloHorizonte, MinasGerais, Brazil
2UniversidadeFederaldeMinasGerais
BeloHorizonte, MinasGerais, Brazil
3DepartmentofPhysicalTherapy
UniversidadeFederaldeMinasGerais
BeloHorizonte, MinasGerais, Brazil
4UniversidadeFederaldeMinasGerais
BeloHorizonte, MinasGerais, Brazil
5DepartmentofPhysicalTherapy
UniversidadeFederaldeMinasGerais
BeloHorizonte, MinasGerais, Brazil
6DepartmentofPhysicalTherapy
UniversidadeFederaldeMinasGerais,
BeloHorizonte, MinasGerais, Brazil
EUR J PHYS REHABIL MED 2013;49
M. B. PINHEIRO 1, J. C. POLESE 2, C. D. C. M. FARIA 3, G. C. MACHADO 4
V. F. PARREIRA 5, R. R. BRITTO 5, L. F. TEIXEIRA-SALMELA 6
Background. Respiratory muscular weakness and as-
sociated changes in thoracoabdominal motion have
been poorly studied in stroke subjects, since the indi-
viduals’ functional levels were not previously consid-
ered in the investigations.
Aim. To investigate the breathing patterns, thoracoab-
dominal motion, and respiratory muscular strength in
chronic stroke subjects, who were stratied into two
groups, according to their walking speeds.
Design. Cross-sectional, observational study.
Setting. University laboratory.
Population. Eighty-nine community-dwelling chronic
stroke subjects
Methods. The subjects, according to their gait speeds,
were stratied into community (gait speed ≥0.8 m/s)
and non-community ambulators (gait speed <0.8 m/s).
Variables related to pulmonary function, breathing
patterns, and thoracoabdominal motions were as-
sessed. Measures of maximal inspiratory pressure
(MIP) and maximal expiratory pressure (MEP) were
obtained and were compared with the reference val-
ues for the Brazilian population. The MIP and MEP
values were expressed as percentages of the predict-
ed values. Mann-Whitney-U or independent Student
t-tests were employed to compare the differences be-
tween the two groups for the selected variables.
Results. No signicant between-group differences
were found for the variables related to the breath-
ing patterns and thoracoabdominal motions (0.01<z/
t<1.51; 0.14<P<0.99). Compared to the predicted
values, the stroke subjects demonstrated decreases
of 26.5 and 20% of the MIP and MEP, respectively.
Non-community ambulators showed signicant lower
predicted MIP values than those from the community
Corresponding author: L. Fuscaldi Teixeira-Salmela, PhD, De-
partamento de Fisioterapia, Universidade Federal de Minas Gerais,
Avenida Antônio Carlos, 6627, Campus Pampulha, 31270-901 Belo
Horizonte, Minas Gerais, Brazil. E-mail: lfts@ufmg.br
Anno: 2013
Mese: ??
Volume: 49
No: 1
Rivista: EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE
Cod Rivista: EUR J PHYS REHABIL MED
Lavoro: 3280-EJPRM
titolo breve: Inspiratory muscular weakness
primo autore: PINHEIRO
pagine: 1-2
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PINHEIRO INSPIRATORY MUSCULAR WEAKNESS
2 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE Vol. 50 - 2014
spiratory muscles 3 and may compromise the respi-
ratory function of these individuals.4
Declines in respiratory function have been shown
to be independent predictors of coronary and car-
diovascular mortality and morbidity.5 In addition,
respiratory muscular weaknesses, when associated
with changes of the thoracoabdominal motions,
could be related to decreased tidal volumes (VT)
and exercise tolerance.6
Studies have reported the importance of maintain-
ing the strength of respiratory muscles and have al-
ready demonstrated the relationships between the
respiratory strength and the perceptions of efforts in
individuals with Parkinson’s Disease 7 and with the
functional capacity of various populations, such as
the elderly,8 individuals with chronic obstructive pul-
monary diseases,9 as well as in healthy individuals.10
Weaknesses and strengthening of the peripheral
muscles have been often investigated in stroke sub-
jects.11-13 However, few studies have addressed the
strength of the respiratory muscles. A systematic re-
view, which included four studies related to respi-
ratory strength, demonstrated that, when compared
to controls, stroke subjects showed lower values of
maximal inspiratory pressure (MIP) and maximal
expiratory pressure (MEP).14 However, these stud-
ies included few individuals (n≤18) and people at
both the acute 15-17 and chronic phases after stroke.3
Furthermore, few studies have investigated the pa-
rameters related to breathing patterns and thoraco-
abdominal motions of stroke subjects.3, 15-17
Despite the lack of studies that investigated the
cardiopulmonary parameters in stroke survivors, the
impact and consequences of any health conditions,
such as stroke, can be differentially manifested with
various subjects.18 Therefore, to better understand the
consequences of stroke on the cardiopulmonary sys-
tem, it is important to consider the subject´s function-
al levels. Gait speed has been reported as a powerful
indicator of functioning after stroke, since gait ability
is related to functional independence,19 and higher
speeds are associated with more complex commu-
nity participation and better quality of life.20 In this
sense, Perry et al.21 proposed a stratication of stroke
individuals into two clinically functional groups:
Non-community (gait speed <0.8 m/s) and commu-
nity ambulators (≥0.8 m/s). Community ambulation
has been broadly defined as locomotion outdoors to
encompass activities, such as visits to the supermar-
ket, shopping malls, social outings, and others.21
The identication of respiratory impairments and
their possible relationships with functional capacity
in stroke patients is important to better identify the
group of patients to whom assessments and perhaps
specic interventions should be emphasized. There-
fore, the main purpose of this study was to investigate
breathing patterns, thoracoabdominal motions, and
respiratory muscular strength of chronic stroke sur-
vivors, who were stratied into two groups (commu-
nity and non-community ambulators), according to
their functional levels. It was hypothesized that sub-
jects with lower functional levels would demonstrate
decreases of respiratory strength and changes in the
breathing patterns and thoracoabdominal motion.
Materials and methods
Participants
One-hundred subjects were recruited from the gen-
eral community of the city of Belo Horizonte, Brazil,
according to the following criteria: Were older than
20 years; had the time since the onset of a unilateral
stroke of at least six months; demonstrated residual
weakness and/or increased tonus of the paretic low-
er limb, determined by strength decits above 10%
and/or scores on the modied Ashworth scale dif-
ferent from zero, respectively; could independently
walk with or without assistive devices; had no facial
palsy, which could prevent proper labial occlusion;
and had no cognitive impairments, as assessed by
the Mini Mental State Examination,22 according to the
cut-off scores, recommended by Brucki et al.23 They
also should be able to understand and perform the
test procedures. Eligible participants provided con-
sent prior to screening, based upon approval from
the university ethical review board.
Measurement instruments and procedures
The assessments were carried out over two con-
secutive days and the same measurement orders
were employed. During the rst day, the participants
underwent a physical examination and interviews to
obtain their demographic, anthropometric, and clini-
cal information related to age, gender, body mass,
height, paretic side, time since the onset of stroke, use
of medications, and smoking habits. For characteriza-
tion purposes, pulmonary function tests were also
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(either sporadically or systematically, either printed or electronic) of the Article for any purpose. It is not permitted to distribute the electronic copy of the article through online internet and/or intranet file sharing systems, electronic mailing or any other
means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
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INSPIRATORY MUSCULAR WEAKNESS PINHEIRO
Vol. 50 - 2014 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE 3
ing inspiration and expiration, respectively, whereas
the PhaseAng reected the delay between the rib
cage and abdomen excursions.31
Then, measures of MIP and MEP were obtained
with a previously calibrated manovacuometer
(GeRar®, Brazil), with operating intervals of ±300
cm H2O. Assessments of MIP and MEP have been
used as indirect measures of strength of the inspira-
tory and expiratory musculature, respectively.3 This
test has shown appropriate psychometric proper-
ties.32, 33
All MIP and MEP measures were performed with
the participants comfortably seated on a chair with-
out trunk support, with their feet on the ground and
their trunk positioned at an angle of 90° in relation
to their hips. A nose clip was used and a mouthpiece
was tightly held between the lips during all maneu-
vers, to avoid leaks. To record the MIP, participants
were instructed to exhale into the mouthpiece to re-
sidual volume and, then, perform a maximal inspir-
atory effort against an obstructed airway.34, 35 The
MEP was recorded in a similar way, and the subjects
were instructed to breathe from the mouthpiece to
total lung capacity and, then, perform a maximal
expiratory effort. One-minute rest intervals were al-
lowed between the trials and immediately after two
familiarization trials,34 the participants were asked
to perform the tests until three acceptable measures
were obtained without an air leak for at least a one
second of duration.34 Two reproducible maneuvers
with a maximum 10% variation, were retained and
the highest value was selected for analysis.34,35 The
MIP and MEP values were compared with the pre-
dicted ones, by employing the following equations
proposed by Neder et al.:34
MIP: Women: y = −0.49 (age) + 110.4; standard
error of the estimate =9.1
Men: y = −0.80 (age) + 155.3, standard error of the
estimate =17.3
MEP: Women: y = −0.61 (age) + 115.6; standard
error of the estimate =11.2
Men: y = −0.81 (age) + 165.3; standard error of the
estimate =15.6
Statistical analyses
Descriptive statistics, test for normality (Shapiro-
Wilk or Kolmogorov-Smirnov tests) and for equal-
ity of variances (Levene) were carried out for all of
the investigated variables. The MIP and MEP values
performed using a spirometer (Vitalograph® 2120, Vi-
talograph Ltd, UK), following the recommendations
for data acquisition, quality, and reproducibility.24
Gait speed was assessed to determine the partici-
pants’ functional levels. The subjects were instructed
to walk at self-selected comfortable speeds along a
28m hallway wearing their usual shoes and assistive
devices. The time spent to cover the central 24m was
recorded with a digital stopwatch and the speed (m/s)
was calculated. Three trials were collected and the
average values were stored for analyses.3 Based upon
the gait speed values, the subjects were stratied into
two clinically functional groups: Non-community
(speed <0.8 m/s) and community (≥0.8 m/s) ambula-
tors.21 A time break of at least one hour was ensured
for all subjects between the spirometry and gait speed
tests, to guarantee that they were fully recovered.
During the second day, the breathing patterns and
thoracoabdominal motions were assessed with the
respiratory inductive plethysmography (Respitrace®
204, Nims, USA), which has shown to be a simple
and accurate method to identify the tidal volume,
respiratory frequencies, and time of inspiration
and expiration during the respiratory cycle.25-27 The
breathing patterns and thoracoabdominal motion
components were obtained by the changes in the
cross-sectional areas of the rib cage and abdominal
compartments.28
The participants were asked to comfortably lie
down in the supine position on an examination
table with inclination of 30° for 30 minutes 3, 29
and were instructed not to talk, sleep, or move
any part of their body during data collection. The
equipment calibration was performed, following
standardized procedures.3, 30 The signals were ob-
tained using specic software (RespiEvents, Nims,
USA) for 10 minutes. To analyze the data, inter-
vals of at least 30 seconds of stable respiratory
cycle tracings were selected. In addition, the sum
of these intervals should reach a minimum of ve
minutes.30
The following variables were obtained from the
respiratory cycle: Tidal volume (VT), respiratory rate
(RR), minute ventilation (VE), inspiratory duty cycle
(TI/Ttot), mean inspiratory ow (VT/TI), percentage
of rib cage motion (%RC), phase relation in inspira-
tion (PhRIB), phase relation in expiration (PhREB),
and phase angle (PhaseAng). The PhRIB and PhREB
reected the percentage of the time that the rib cage
and the abdomen moved in opposite directions dur-
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means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
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PINHEIRO INSPIRATORY MUSCULAR WEAKNESS
4 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE Vol. 50 - 2014
mass, height, body mass index, time since the onset
of the stroke, use of medication, and spirometric
variables (0.33<t<1.54; 0.07<P< 0.75). All individ-
uals of both groups did not have any respiratory
complaints.
As seen in Table II, no signicant between-group
differences were found for any of the variables relat-
ed to the breathing patterns and thoracoabdominal
motions (0.01<z/t<1.51; 0.14<P<0.99).
Table III provides the data related to the meas-
ures of maximal respiratory pressures stratied into
the two functional levels. Compared to the predicted
values, decreases of 26.5 and 20% were found for
the MIP and MEP, respectively. The non-community
ambulators showed signicant lower predicted MIP
values than those of the community ambulators
(t=-2.10; P=0.04). However, no signicant between-
group differences were found for the predicted MEP
measures (t=-1.10; P=0.25).
Discussion
To the best of our knowledge, this is the rst study
that investigated the parameters of respiratory func-
were expressed as percentages of the predicted val-
ues, according to the following formula: (observed
value/predicted value * 100). Mann-Whitney-U or in-
dependent Student t-tests were employed to inves-
tigate the differences between the community and
non-community ambulatory groups for all selected
variables. All analyses were carried out with the
SPSS version 17.0 for Windows with a signicance
level of 5%.
Results
Eleven subjects, ve from the community and six
from the non-community ambulation group, were
excluded either because the subjects were not
able to complete the tests or due to the inductive
plethysmography measurement artifacts. Therefore,
out of the 89 individuals who completed all the
tests (48 men and 41 women), 57 (64%) were classi-
ed as community and 32 (36%) as non-community
ambulators. Table I shows the participants’ demo-
graphic, clinical, anthropometric, and spirometric
characteristics. No signicant differences between
the groups were found regarding their ages, body
Table I.—Demographic, clinical, anthropometric, and spirometric characteristics of the participants.
Characteristic
Community
ambulators
(N.=57)
Non-community
ambulators
(N.=32)
Total
(N.=89)
Age (years), mean ± SD
range: min-max
54.8±11.9
(24-82)
57.9±12.1
(31-79)
56.2±12.0
(24-82)
Gender, male (%) 35 (61.4) 14 (43.8) 48 (53.9)
Body Mass (kg), mean ± SD
range: min-max
70.3±13.4
(40-101)
65.5±15.5
(44-106)
68.1±13.9
(40-106)
Height (m), mean ± SD
range: min-max
1.63±0.08
(1.45-1.79)
1.60±0.11
(1.44-1.86)
1.62±0.09
(1.44-1.86)
BMI (kg/m2), mean ± SD
range: min-max
26.3±4.0
(15.2-36.5)
25.1±3.6
(19.0-32.9)
25.8±4.0
(15.2-36.5)
Paretic side, right (%) 37 (64.9) 14 (43.8) 51 (57.3)
Time since onset of the stroke (months), mean ± SD
range: min-max
60.7±52.8
(6-228)
70.3±56.4
(6-240)
64.2±54.0
(6-240)
Use of medications (number), mean ± SD
range: min-max
3.0±1.8
(0-8)
2.9 ±1.6
(0-6)
2.9±1.7
(0-8)
Smokers, number (%)
Non-smokers, number (%)
Ex-smokers, number (%)
9 (15.8)
16 (28.1)
32 (56.1)
2 (6.3)
19 (59.4)
11 (34.4)
11 (12.4)
35 (39.3)
43 (48.3)
FEV1 (% predicted), mean ± SD
range: min-max
86.7±20.0
(46.8-159.0)
80.5±16.5
(46.9-111.8)
84.6±19.0
(46.8-159)
FVC (% predicted), mean ± SD
range: min-max
89.7±18.6
(46.7-159)
82.0 ±15.7
(45.8-109.5)
87.3±17.9
(45.8-159)
FEV1/FVC (% predicted), mean ± SD
range: min-max
97.8±8.3
(72.9-111.1)
98.4±7.8
(80.5-114.8)
98.0±8.1
(72.9-114.8)
BMI: body mass index; FEV1: forced expiratory volume in the rst second; FVC: forced vital capacity.
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means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
not permitted. It is not permitted to remove, cover, overlay, obscure, block, or change any copyright notices or terms of use which the Publisher may post on the Article. It is not permitted to frame or use framing techniques to enclose any trademark, logo,
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INSPIRATORY MUSCULAR WEAKNESS PINHEIRO
Vol. 50 - 2014 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE 5
to reduced tolerance to exercise,6, 37 which restricts
social participation of these individuals.37 However,
there were not found statistical differences regarding
these variables between the community and non-
community ambulators. It appears that these param-
eters are not easily affected by changes at the func-
tional levels.
The participants of the present study demonstrated
reduced maximal respiratory pressure values, which
were similar to those found by Teixeira-Salmela et
al.,3 who reported MIP values of 73 cmH2O and MEP
of 89 cmH2O. However, lower values were found by
Lanini et al.15 (MIP of 55 cmH2O and MEP of 61
cmH2O). Harraf et al.16 and Ward et al.17 also found
lower MEP values (62 cmH2O and 50 cmH2O, re-
spectively) than those observed in the present study.
These differences could be partially explained by
the fact that the above studies investigated stroke
subjects during the acute stages,15-17 and employed
different methodological procedures, which could
also justify these differences.
Despite the reduction in respiratory pressure val-
ues, the participants did not have either respiratory
symptoms nor complaints. According to the ndings
of Hautmann et al.,38 MIP has to be approximately
tion in a large group of stroke subjects at chronic
stages, stratied according to their functional lev-
els. Regarding the breathing patterns and thoraco-
abdominal motions, no between-groups differences
were found. The stroke subjects showed respiratory
muscular weaknesses and signicantly lower pre-
dicted MIP values were observed for the non-com-
munity ambulators, who had lower functional levels.
The only previous study, which analyzed data on
breathing pattern characteristics with a similar sam-
ple, was Teixeira-Salmela et al.,3 who observed simi-
lar values to those found in this study, despite their
reduced sample size. Parreira et al.30 investigated the
breathing patterns and thoracoabdominal motions
of healthy Brazilian individuals, recruited from the
same community as this study. Although the posi-
tioning adopted by the subjects during data collec-
tion was different (supine at 0o) from that of the
present study, all of the other procedures were simi-
lar. Overall, the stroke subjects showed lower values
of VT, VE and VT/TI, higher values of fR, PhRIB,
%CT and similar values for the remaining variables,
when compared to healthy subjects.30, 36 Although
statistical analyses were not performed, the appar-
ent volume reductions in stroke subjects may lead
Table II.—Descriptive data and comparisons of the variables related to the breathing patterns and thoracoabdominal motions
between the community and non-community ambulators.
Variable Community ambulators
(N.=57)
Non-community ambulators
(N.=32)
Total
(N.=89) t or z; P values
VT (mL) 270 (224-341) 261 (195-365) 269 (207-345) 0.36; 0.72
fR (bpm) 17 (15-19) 16 (15-19) 17 (15-19) 0.01; 0.99
VE (L/min) 4.62 (3.98-5.69) 4.51 (3.69-5.56) 4.62 (3.77-5.66) 0.60; 0.55
TI/Tot (%) 0.40 (0.38-0.43) 0.39 (0.36-0.42) 0.40 (0.37-0.42) 1.51; 0.14
VT/TI (mL/s) 195 (165-244) 194 (152-240) 196 (162-239) 0.23; 0.82
%RC 38 (29-49) 43 (34-50) 40 (31-49) 1.32; 0.19
PhRIB (%) 9 (6-13) 8 (6-14) 9 (6-14) 0.35; 0.73
PhREB (%) 12 (8-19) 15 (9-21) 13 (9-19) 0.41; 0.68
PhaseAng (o) 13 (9-19) 12 (7-19) 13 (7-20) 0.17; 0.87
Data were expressed as medians and interquartile intervals. VT: Tidal volume; fR: Respiratory rate; VE: Minute ventilation; TI/Tot: inspiratory duty cycle;
VT/TI: mean inspiratory ow; %RC: rib cage motion; PhRIB: phase relation in inspiration; PhREB: phase relation in expiration; PhaseAng: phase angle.
Table III.—Descriptive data and comparisons of the respiratory pressures between the community and non-community ambula-
tors.
Variable Community ambulators
(N.=57)
Non-community ambulators
(N.=32)
Total
(N.=89) t, P values
MIP (cmH2O) 79.5±30.6 62.8±24.1 73.5±29.5 NA
MIP (% predicted) 79.9±30.8 66.1±23.4 74.4±28.4 -2.10, 0.04
MEP (cmH2O) 87.7±40.1 73.0±31.1 82.4±37.6 NA
MEP (% predicted) 82.8±34.5 75.0±27.7 80.0±32.3 -1.10, 0.25
Data were expressed as means±SD. MIP: maximal inspiratory pressure; MEP: maximal expiratory pressure; NA: not applicable.
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PINHEIRO INSPIRATORY MUSCULAR WEAKNESS
6 EUROPEAN JOURNAL OF PHYSICAL AND REHABILITATION MEDICINE Vol. 50 - 2014
lationships between the studied variables cannot be
determined. Additionally, low gait speed could be
a consequence of a low cardiorespiratory function,
but this was not assessed. The participants were also
not uniformly stratied into the groups, which may
have inuenced the results. It is important to point
out that only individuals with chronic hemiparesis,
who demonstrated ability to walk independently
were included. Thus, the present ndings cannot be
generalized to subjects with different characteristics,
such as being in the acute or sub-acute stages or
unable to walk.
Conclusions
No signicant differences between the commu-
nity and non-community ambulators were found for
any of the variables related to the breathing pat-
terns and thoracoabdominal motions. Lower respira-
tory strength values were demonstrated by chronic
stroke subjects. When the subjects were stratied
into two functional levels, lower predicted MIP val-
ues were found for the non-community ambulators.
It is possible that interventions involving respiratory
muscular training should be included in stroke reha-
bilitation, especially for individuals with lower func-
tional levels.
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Limitations of the study
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tion is that due to the nature of the study, causal re-
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means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
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INSPIRATORY MUSCULAR WEAKNESS PINHEIRO
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One abstract of the present paper was presented at the 8th World
Stroke Congress held in Brasilia, Brazil, October 10-13, 2012.
Funding.—Brazilian National funding agencies: Coordena-
ção de Aperfeiçoamento de Pessoal de Nível Superior (grant
#NF2322/2008), Conselho Nacional de pesquisa (CNPq grant #
501645/2010-1), and Fundação de Apoio a Pesquisa do Estado
de Minas Gerais (FAPEMIG (grant # PPM-00023-10).
Conicts of interest.—The authors certify that there is no conict
of interest with any nancial organization regarding the material
discussed in the manuscript.
Ethical approval.—This study was approved by the ethical re-
view board of the Universidade Federal de Minas Gerais (UFMG),
under the protocol number: ETIC 05380.0.203.000-09.
Received on May 27, 2013.
Accepted for publication on September 25, 2013.
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means which may allow access to the Article. The use of all or any part of the Article for any Commercial Use is not permitted. The creation of derivative works from the Article is not permitted. The production of reprints for personal or commercial use is
not permitted. It is not permitted to remove, cover, overlay, obscure, block, or change any copyright notices or terms of use which the Publisher may post on the Article. It is not permitted to frame or use framing techniques to enclose any trademark, logo,
or other proprietary information of the Publisher.