Effect of Different Volumes of Training of Pilates Exercises on Muscle Strength, Postural Balance, Flexibility, Functional Autonomy, Depressive Symptoms and Pulmonary Function on Elderly
Phase: NA
Conditions: Aging, Exercise Movement Techniques
Sponsor: University of Brasilia

 
 
 
 
 
Effect of Different Volumes of Training of Pilates Exercises on 
Muscle Strength, Postural Balance, Flexibility, Functional Autonomy, 
Depressive Symptoms and Pulmonary Function on Elderly 
 
 
 
NCT03791502 
 
SEPTEMBER 17, 2019 
 
 
 
 
 
 
 
 
 
 
 

 
ABSTRACT 
 
Background: aging is a progressive process that leads to decreased muscle 
strength and mobility, slowness in reaction time and impaired balance, 
compromising autonomy and quality of life. Objective: to compare the effect of 
different volumes of Pilates training on strength, balance, flexibility, functional 
autonomy, depressive symptoms and pulmonary function in the elderly 
community. Method: it will be a randomized clinical trial with elderly of both 
sexes. The Group A (GA) exercises with smaller volume and greater variability of 
exercises, Group B (GB) greater volume and lower variability and Group C (CG) 
will maintain its usual activities. The intervention will occur twice a week for 60 
minutes for 12 weeks. In order to evaluate the strength, Biofeedback System for 
resting exercises with elastic overload (E-lastic®), 30-second chair stand test (30-
s CST) and Palmar gripper dynamometer will be used. The balance will be 
evaluated in the semi-tandem, tandem and unipodal positions, by the Timed Up 
and Go (TUG) and Step Test. Flexibility will be assessed using the Wells 
database, functional autonomy, dressing-gown test (VTC), depressive symptoms 
by the Geriatric Depression Scale (GDS) and lung function by many vacuum and 
spirometry. Data distribution will be done using the Shapiro-Wilk test, frequency 
and percentage calculation for categorical variables, the mean and standard 
deviation for continuous variables with normal, median, and interquartile 
distribution for variables with non-normal distribution. For comparison of the three 
groups will be used ANOVA One Way with post hoc of Bonferroni or Kruskal 
Wallis with Bonferroni correction, comparison of the continuous variables at 
moments before and after twelve weeks of intervention the Student's t-test paired 
or Wilcoxon and for the comparison of the categorical variables the test chi-
square. Expected results: significant improvement of outcomes in both 
intervention groups compared to CG, however, the group with higher training 
volume and lower exercise variability will have a greater effect than the group 
with lower volume and greater variability of exercises. Keywords: Exercise 
Movement Techniques, Elderly, Aging, Muscular Strength, Balance, and 
Flexibility 

 
Introduction 
Aging is an involuntary and progressive process that leads to biological, 
structural and functional changes such as loss of mass and muscle strength(1,2). 
The aging process leads to changes in the visual, vestibular, sensory and motor 
systems, causing slow reaction time, compromising the postural balance (L. (3,4) 
Flexibility and mobility also tend to decrease with aging favoring the onset of 
lesions and loss of functional autonomy (5,6). The regular practice of physical 
exercise helps to prevent these changes related to aging (5). 
Among the various possibilities of physical exercise, the Pilates method 
has been well-suited for the elderly, since it incorporates the training components 
recommended by the American College of Sports Medicine (ACSM), is the 
strength, balance, and flexibility (7,8). However, researchers have questioned the 
lack of scientific evidence that confirms all the benefits of the method, especially 
in the elderly,(9,10). The findings described in the literature are still controversial. 
A systematic review of six randomized controlled trials (RCTs) has shown limited 
evidence in improving strength, flexibility, and balance in both sexes (9). 
Physical decline negatively affects the personal autonomy and quality of 
life of the elderly and Pilates seems to have positive effects on these aspects. 
Rodrigues et al. (2010)(11) observed a significant evolution in the functional 
performance of healthy elderly women in rising from the seated position (11.8%) 
and lying position (26%) and a significant improvement in quality of life (p = 0.04) 
after intervention with Pilates exercises (11). As for depressive symptoms, 
Mokhtari et al. (2013)(12) identified a significant reduction (p <0.007) in this 
symptomatology after Pilates practice (12). However, both studies reached only 
two points on the PEDro Scale. Recent investigations found a significant increase 
in maximal inspiratory pressure (MIP) of 19.5%, maximal expiratory pressure 
(MEP) of 8.7% and Abdominal Transversal thickness of 42.3% after the 
program(13). However, the study presented some limitations, such as the 
absence of a control group and the inability of the blindness of the evaluators. 
It is also important to highlight the lack of reports on how the programs are 
carried out and when there is a description there is a heterogeneity in the 
prescription of the exercises. In the two reviews cited above (9,14), only two of 

the included studies presented the prescribed volume: ten replicates (11)and 
three series of ten repetitions (15). Some studies have also described the volume: 
two sets of ten repetitions (16), two to four sets of 15 to 20 seconds of contraction 
for isometric exercises and 15 to 20 repetitions for dynamic exercises (17). A 
single series of 10 replicates with a 30-second interval between the series 
(18,19). It is known that the literature suggests for the muscular strength gain in 
the elderly a training volume of two to three sets per exercise, seven to ten 
repetitions per set and a moderate to high intensity (8,20) and as noted most 
Pilates exercise programs have not followed these recommendations.  
The aim of the study is to compare the effect of different volumes of Pilates 
exercise training on muscle strength, postural balance, flexibility, functional 
autonomy, depressive symptoms and lung function in the elderly community. We 
believe that Pilates exercises will have beneficial effects for the elderly, but our 
hypothesis is that the group that performs a greater volume of Pilates exercise 
training will have a greater improvement in the investigated outcomes than the 
group with the lowest volume. 
Methods 
Type and location of study 
This is a randomized clinical trial, which will be conducted at a Pilates 
studio in Goiânia. 
Participants 
The elderly will be invited through advertisements in social networks, local 
media, and posters distributed in the centers of coexistence of the elderly, health 
centers and churches and will be selected, considering the possibility of 20 % of 
sample losses, the first 57 eligible participants according to the following inclusion 
criteria:  
• Age between 60 and 85 years; 
• To present cognitive aptitude according to the Mental State Mini-Exam 
(MMSE); 
• Independent walking, without the use of auxiliary walking devices; 
• Not participating in other physical intervention research; 

• Not having undergone physiotherapeutic treatment and not having 
participated in a structured physical activity in the previous month; 
• Do not present neurological diseases, history of fractures or recent 
surgeries and serious cardiorespiratory diseases. 
Participants will be excluded: 
• Failure to attend all stages of evaluation; 
• They did not complete 80% of the intervention. 
Outcomes and Measuring Instruments 
The dependent variables of the present study will be muscle strength, postural 
balance, flexibility, functional autonomy, depression and pulmonary function. 
Muscle Strength 
The muscle-dependent variable will be evaluated through the Biofeedback 
System for The Biofeedback System will be used for the practice of resistance 
exercises with elastic overload (E-lastic®), The 30-second chair stand test (30-s 
CST), and the palmar gripper dynamometer 
• The Biofeedback System will be used for the practice of resistance 
exercises with elastic overload (E-lastic®). E-lastic® will measure maximal 
isometric voluntary contraction of the knee flexor and extensor muscles, 
flexors, extensors, adductors and hip abductors before and after the 
intervention. For the acquisition of force signals, a load cell is used to 
provide an electrical signal proportional to the force that deforms the 
equipment. The participants will perform 3 repetitions, maintaining the 
contraction for 5 seconds, with 60 seconds of recovery and the highest 
value will be recorded. 
• The 30-second chair stand test (30-s CST) will be used. It consists of 
getting up and sitting on a chair as many times as possible within 30 
seconds. A seat with backrest and without armrest (with a seat height of 
45 cm) is used. Initially, participants remain seated and are instructed to 
look forward after command "1, 2, 3, will" they raise with their arms crossed 
on their chest. The evaluator will explain and demonstrate the test and the 
participant will do once for familiarization. You will be given a rest of 2 
minutes to start the test. 

• Will be measured using the Saehan® hydraulic palmar gripper 
dynamometer, the position recommended by the American Society of 
Hand Therapists (ASHT) will be adopted: sitting comfortably positioned 
with shoulder lightly bent, elbow bent at 90 °, forearm in neutral position 
and, finally, the position of the handle may vary from 0 ° to 30 ° of 
extension. It will be used to record the maximum and average manual grip 
strength of three measurements and the values will be compared with the 
reference values. 
Postural balance 
The static and dynamic body balance will be evaluated. 
• Static postural balance: will be evaluated by measuring the time each 
participant can maintain in three progressively more difficult positions: 
semi-tandem, tandem and unipodal support. In all positions the individuals 
must be with their hands on their waist, the total time to stay in each 
position is 30 seconds and it will have 3 attempts in each position and the 
best time will be recorded. The evaluator will demonstrate the test once. 
• Dynamic postural balance: to evaluate the dynamic balance, the Timed Up 
and Go (TUG) test and the Step Test will be used. The TUG starts with the 
participant sitting in the chair, in the "go" command, he gets up from the 
chair, walks 3 meters at a comfortable pace, turns around, goes back to 
the chair and sits down. It will be demonstrated once and then it will do a 
repeat for familiarization. In the Alternative Step Test, the participant is 
asked to make eight beats of the foot, alternating between right and left, 
on a step in front of him with a height of 18 cm. Time will be timed and 
used in the analyzes. The test should be performed in 10 seconds. 
Flexibility 
To evaluate the flexibility of the hamstring muscles will be used the Sit and 
Go Test, using the Wells bench, participants will remain without footwear, sitting 
with knees extended, shoulders flexed, elbows extended and hands overlapped. 
Participants should perform trunk flexion at the front, perform a forced expiration, 
and move the seat ladder as far as possible, this procedure will be performed 
three times and immediately noted by the evaluator, with the best. 

Functional Autonomy 
The functional autonomy of the upper limbs will be evaluated by the 
dressing test and a t-shirt. Initially, the evaluator will explain the test and the 
volunteer will do a brief training with two replicates. The execution time is marked 
in seconds and the shorter the execution time, the better the result. The subject 
must make two attempts, where the best performance attempt will be recorded. 
Depressive symptoms 
The Geriatric Depression Scale will be used for the evaluation of 
depressive symptoms in the elderly and screening for depression among older 
people. Geriatric depression scale will be presented as an interview and the 
questions have a yes / no format to be easy to understand. The short version 
consists of 15 questions, one point is given for each "yes" answer and the number 
of points is added to provide a single score. The score ranges from 0 to 15 and a 
score of zero to five is considered normal, six to ten indicates mild depression 
and 11 to 15 suggests severe depression. 
Respiratory muscle strength 
Respiratory muscle strength will be measured by assessing maximal 
inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in cmH2O. 
These measures represent the strength of the inspiratory and expiratory muscles 
respectively. It will be using the manometer of the brand Globalmed® MVD300, 
calibrated, the patient seated at 90º, a nasal clip and a nozzle connected to the 
equipment will be placed. In order to assess MIP, a maximum expiration up to the 
residual volume and, in the sequence, a maximum sustained forced inspiration 
will be required. And to assess PEmax inspiration will be required up to the total 
lung capacity and, subsequently, a forced maximum expiration up to the residual 
volume. Three reproducible measurements will be made, with variation less than 
10% and the values found will be compared with those predicted. 
Pulmonary function 
Pulmonary function will also be evaluated by spirometry. The test measures 
forced vital capacity (FVC) in liters (L), forced expiratory volume in the first second 
(FEV1) in liters (L) and the FEV1 / FVC ratio. A One Flow® portable spirometer 
will be used, the individual will be seated with the head in the neutral position, 
inspiration will be requested up to the total lung capacity (CPT) and, thereafter, a 

maximum expiration, with an explosive start, to the residual volume (lasting at 
least 6 seconds). A maximum of eight replications will be performed until three 
reproducible measures (less than 10% difference), 60 seconds of interval 
between measurements, will be considered the best value. It is recommended to 
compare the values obtained with predicted equations 
 
Sociodemographic, Clinical, Anthropometric and Feasibility Indicators 
To characterize the participants, gender, age, schooling, marital status, 
concomitant diseases, and life habits will be investigated through a 
sociodemographic and clinical characterization questionnaire developed by the 
researchers. A participant who performs at least 150 minutes of moderate 
physical activity or 75 minutes of vigorous physical activity per week will be 
considered active (8,21,22). Body mass and height will be measured to calculate 
the Body Mass Index (BMI). The BMI will be classified according to Lipschitz(23)  
below 22 Kg / m² will be considered lean, between 22 and 27 kg / m² eutrophy 
and over 27 kg / m² overweight. 
Feasibility indicators will be checked by means of the following items: 
retention (percentage of withdrawals and withdrawals), adherence to intervention 
(percentage of Pilates sessions attended and reason for absences), participant 
experience and feedback (Are the sessions pleasant? Pilates for other people? 
Did you realize benefits to your health? Would you like to continue with Pilates 
exercises?), safety (notification of adverse events, be it injury or medical event 
attributable to Pilates exercise). 
Intervention 
The intervention will consist of performing Pilates exercises on the 
apparatus (Reformer, Cadilac, Barrel, and Chair), on the ground and with 
accessories. It will always be performed by a physiotherapist with teaching 
certification in the Pilates methodology and will be supervised by two 
physiotherapist trainees properly trained so that all principles are followed and 
the exercises performed correctly. Participants will start the exercise program in 
small groups of up to 8 people, twice a week for 60 minutes, for 12 weeks, totaling 
24 sessions. 

The first day of intervention for both groups will be devoted to explaining 
the six principles described by Joseph Pilates: centralization, concentration, 
control, precision, fluidity, and breathing, and in all sessions these principles will 
be recalled by the physiotherapist. From the second day of intervention, the 
participants will follow different exercise programs. Group A (GA) will perform a 
training with lower volume and greater variability of Pilates exercises and group 
B (GB) with greater volume and lower variability of Pilates exercises. The control 
group (CG) will remain with their usual activities. The structure of the exercise 
program of each group will be detailed below, but both will start performing 
flexibility exercises, adopting dynamic stretching and then perform the 
strengthening exercises for the main muscle groups. 
• Group A (GA): participants will follow a Pilates exercise program similar to 
that adopted in clinical practice and to what is described in the literature. 
The GA prescription will consist of 18 exercises, performed in a single 
series of seven to 10 repetitions, 60 seconds rest between exercises. Each 
week the exercises will be changed. The progression will occur increasing 
the resistance of the springs and the level of difficulty of the exercises, but 
without modifying the repetitions. The intensity of the training will be 
measured using the Modified Borg Effort Scale and then kept constant 
throughout the program in a score of 7. After the end of each exercise, 
participants will be asked to rate their effort so that the adjustment of the 
intensity can be carried out properly. 
• Group B (GB): participants will conduct a Pilates exercise program based 
on the ACMS recommendations and the results of the systematic review 
of Borde, Hortobágyi, and Granacher (2015). The GB prescription will 
consist of 12 exercises, performed in three sets of seven to ten repetitions, 
the 60s of rest between sets. Every four weeks the exercises will be 
changed. The progression will occur increasing the resistance of the 
springs and the level of difficulty of the exercises. The intensity of the 
training will be measured by the Borg Scale and then kept constant 
throughout the program at level 7. After the end of each exercise, 
participants will be asked to rate their effort so that the intensity adjustment 
can be performed properly. 
 

Evaluation procedures 
Initially, everyone who agrees to participate in the study will sign the 
informed consent form, then the data concerning the variables: cognitive ability, 
sociodemographic, clinical characterization, and anthropometric measurements 
will be collected. All participants will be evaluated for muscle strength, balance, 
flexibility, functional autonomy, depression and lung function before and after the 
intervention, including those who do not complete 80% of their presence during 
the intervention. For the self-report questionnaires an evaluator will be trained 
and for the performance questionnaires/tests two evaluators will be trained and 
they will be blind to the intervention. Subjects will be randomized into three 
groups. The randomization process will be done at random.org and concealment 
of the allocation will occur using opaque and sealed envelopes. 
Statistical analysis plan 
A sample size was calculated using the effect size identified in the 
comparison of the results concerning the post-intervention moment of the 
intervention and control groups, using data from the literature (18,25,26). The 
calculation indicated the need for a sample size of 15 participants per group for 
a power of 80% and an alpha error of 0.05 in the intergroup comparison analyzes 
for the variables muscle strength, balance, and flexibility. 
Initially, the distribution of the data will be determined by means of the 
Shapiro-Wilk normality test. Subsequently, the descriptive analysis will be 
performed with frequency and percentage calculation for the categorical, mean 
and standard deviation data for continuous data with normal distribution and for 
median and interquartile data for continuous data with non-normal distribution. 
For the comparison of the three groups for the performance of the 
continuous data, the ANOVA One Way test with post hoc of Bonferroni or Kruskal 
Wallis with Bonferroni correction (according to the normality of the data) will be 
used. The t-test of paired student or Wilcoxon (according to the normality of the 
data) will be used to compare the continuous data at the before and after 
moments in each group. Comparison of categorical data will be done using the 
chi-square test. For each primary and secondary outcome, the values observed 
in each group will be described, the size of the estimated effect along with its 
accuracy (eg, 95% confidence interval). It will be adopted 5% significance level. 

If necessary, the intention-to-treat analysis will be performed. The data will be 
tabulated with double entry. The analyzes will be performed using SPSS 23.0 
software. 
 
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