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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Note: This article will be published in a forthcoming issue of
the Journal of Physical Activity & Health. This article appears
here in its accepted, peer-reviewed form, as it was provided
by the submitting author. It has not been copy edited, proofed,
or formatted by the publisher.
Section: Systematic Review
Article Title: Effects of Elastic Resistance Training on Muscle Strength and Functional
Performance in Healthy Adults: A Systematic Review and Meta-Analysis
Authors: Poliana Alves de Oliveira1, Juscelino Castro Blasczyk1, Karina Ferreira Lagoa2,
Milene Soares1, Ricardo Jacó de Oliveira1, Paulo José Barbosa Gutierres Filho2, Rodrigo
Luiz Carregaro1, and Wagner Rodrigues Martins1
Affiliations: 1Department of Physical Therapy; 2Department of Physical Education;
University of Brasilia, Brasilia, Brazil.
Running Head: Elastic Training on muscle strength and functional performance
Journal: Journal of Physical Activity & Health
Acceptance Date: November 12, 2016
©2016 Human Kinetics, Inc.
DOI: http://dx.doi.org/10.1123/jpah.2016-0415
“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Abstract
Background: Elastic Resistance Exercise (ERE) has already demonstrated its effectiveness in
older adults and, when combined with the resistance generated by fixed loads, in adults. This
review summarizes the effectiveness of ERE performed as isolated method on muscle
strength and functional performance in healthy adults. Method: A database search was
performed (MEDLine, Cochrane Library, PEDro and Web of Knowledge) to identify
controlled clinical trials in English language. The mean difference (MD) with 95%
confidence intervals (CIs) and overall effect size were calculated for all comparisons. The
PEDro scale was used assess the methodological quality. Results: From the 93 articles
identified by the search strategy, 5 met the inclusion criteria, in which 3 presented high
quality (PEDro > 6). Meta-analyses demonstrated that the effects of ERE were superior when
compared to passive control on functional performance and muscle strength. When compared
to active controls, the effect of ERE was inferior on function performance and with similar
effect on muscle strength. Conclusion: ERE are effective to improve functional performance
and muscle strength when compared to no intervention, in healthy adults. ERE are not
superior to other methods of resistance training to improve functional performance and
muscle strength in health adults.
Key words: elastic bands, strength training, effect size.
Abstract word count: 198.
Manuscript word count: 5303.
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Introduction
Resistance exercise (RE) is an intervention modality characterized by a muscle work
against an external force and commonly used for strength and functional benefits1. As muscle
strength improvements are related to disability and fitness, RE could be used as an effective
intervention to improve muscle function in adults2,3and elderly individuals4–7.
Different types of equipment can be used during RE interventions. Recent guidelines
related to this topic recommended the use of free weights, weights/pneumatic machines and
resistance elastic bands for developing and/or maintaining musculoskeletal fitness3.
Notwithstanding, the guidelines presented strong evidence and specific recommendations
(evidence category A) regarding the use of free-weight and machine exercises in progression
models of RE to improve muscle strength of novice to intermediate health adults and also
older adults1. Weight machines are popular among scientific and health allied professionals
because is considered safe and allows the performance of exercises that may be less practical
when performed with free weights (e.g. knee extension). Unlike the machines, free weights
may increase the patterns of intermuscular coordination, which simulates some movements
required in activities of daily living.
Considering that RE with machines and free weights are currently considered the gold
standard for strength muscle increases, previous studies investigated whether alternative and
complementary methods are also effective. From a practical stand point, some studies have
employed elastic resistance exercise (ERE) as a model of choice for older adults to improve
muscular strength8–12. Additionally, previous systematic reviews demonstrated that ERE were
considered effective to improve muscle strength of older adults2,13. Historically, elastic bands
have been used in hospital settings for rehabilitation and conditioning14. Also, ERE is widely
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
used in fitness and sports training programs on health adults due to its ease-of-use15 and
adequate control of the exercise intensity16,17.
Regarding the use of ERE on the adult population, there is emerging evidence on how
this type of RE allows muscle strength in trained and untrained adults. In a first systematic
review, long term (> 7 weeks) variable resistance training using chains or elastic bands
attached to the barbell in bench press or back squat exercise emerged as an effective method
for improving muscle strength in athletes and untrained subjects18. Unfortunately, this
evidence was provided in the context of ERE combined with the resistance generated by
fixed loads (e.g. barbell and discs) and only to 1RM test as outcome of muscle strength. In
the present review we employed new perspective regarding the effects of ERE on muscle
strength, and randomized clinical trials (RCT) that adopted ERE as the sole RE strategy were
included. Accordingly, the outcomes were not specific ones (such as 1RM test), but direct
and indirect outcomes related to muscle strength. Considering this context, it is hypothesized
that there is evidence to support the use of ERE as an isolated method to increase muscle
strength across different outcomes in healthy adults.
The aim of this systematic review was to summarize evidence related to the
effectiveness of ERE on muscle strength and functional performance in healthy adults and to
compare passive and active control groups adopted by randomized clinical trials (RCTs).
Materials and Methods
Preliminary settings
This review was registered in PROSPERO under the number: CRD42015027002
(http://www.crd.york.ac.uk/PROSPERO/) and was reported according to the Preferred
Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA; http://www.prisma-
statement.org).
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Literature Search Strategy
A computerized literature search was conducted in the following databases:
MEDLine, The Cochrane Library, PEDro (Physiotherapy Evidence Database) and ISI Web of
Knowledge, last searched in March 12, 2016 and without date restriction. The descriptors
were obtained from the Medical Subject Headings of the National Library of Medicine (Mesh
database). As the descriptors “elastic bands” or “elastic tubes” were not registered in the
Mesh, the search adopted the most prevalent descriptors included in the study’s titles within
this scientific field. The following search strategy was adopted (combining a maximum of
two descriptors): (“elastic bands” OR “elastic resistance” OR “elastic tubing” OR “elastic
band exercise” OR “elastic band resistance”) AND (“resistance” OR “strength” OR
“resistance training” OR “strength training” OR “muscle strength” OR “exercise movement
techniques” OR “exercise therapy” OR “exercise programs”). Limits were used when
appropriate: RCT, clinical trial, human trials, written in English. The PRISMA flow diagram
is presented in Figure 1.
Study Inclusion and Exclusion Criteria
Only RCTs in the English language and available online were included in order to
investigate the effects of RE with elastic bands on outcomes of muscle strength and
functional performance. The inclusion criteria were: (I) health subjects aged between 18-59
years old; (II) direct (e.g. one repetition maximum [1RM], multiples repetition maximum,
maximal voluntary isometric contraction [MVIC], isokinetic peak torque) or indirect (e.g.,
functional tests like: knee push up test, 60 squat test, 30 second sit to stand test, abdominal
crunch) measures; (III) randomized controlled trials. As an operational definition, resistance
training was considered an exercise that require a muscle to exert force against external
resistance, combining static and dynamic contractions (available at
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
http://www.ncbi.nlm.nih.gov/mesh/). In the present study, all types of elastic devices (bands
or tubes) were considered as load that induced responses during the resistance training. The
following exclusion criteria were considered: (I) studies in which individuals had a history of
musculoskeletal surgery; (II) individuals with rheumatoid arthritis, fractures, malignancies,
any kind of systemic diseases; (III) athletes (IV) interventions in which the ERE was used in
combination with other methods of resistance training (e.g., ERE plus free weights vs. free
weights).
Study Selection
Two authors, independently, screened titles and abstracts. Potential eligible studies
were full read. The reference list of the included studies was consulted for additional studies.
Disagreements were resolved by consensus between the two reviewers.
Methodological Quality Assessment
The methodological quality of the included RCTs was scored using the PEDro scale.
The PEDro scale consists of 11 criteria (random allocation; concealed allocation; baseline
comparability; blind subjects; blind therapists; blind assessor; adequate follow up; intention-
to-treat-analysis; between groups comparisons; point estimates and variability), which
receives either a “yes”, or “no” rating. As criteria 1 is not used in the calculation, the
maximum PEDro score is 10 points. Trials with a PEDro score ≥ 6 points were classified as
high-quality, while trials with a PEDro score < 6 points were classified as low-quality. The
studies were assessed with the Brazilian-Portuguese version of the PEDro scale19.
Comparisons
Studies with any active (e.g., weight machines, free weights, aquatic resistance
devices) or passive (e.g., no intervention, waiting list) control groups were considered to
perform the meta-analysis. Experimental groups (i.e. ERE) were compared to control groups,
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
separately. In addition, the meta-analysis considered the following outcomes: (I) outcomes of
muscle strength (e.g. maximal voluntary isometric contraction [MVIC]) and functional
performance (e.g. knee push up test); (II) body regions in which the measure was applied (i.e.
upper, lower and trunk). Accordingly, forest plots were generated considering an overall and
subgroup meta-analysis.
For the meta-analysis, it was considered the outcome measures closest to the last time
point measurement, even if studies adopted various time point measurements (e.g. follow
ups), thus, the first post-intervention measurement was chosen.
Statistical Analysis
Considering that the included studies employed similar outcomes measurements
(units and scales), the Mean Difference (measures the absolute difference between the mean
values in two groups in a clinical trial) and 95% of the Confidence Intervals were considered
in the meta-analysis procedure20.
Data required for calculating the Mean Difference (MD) for continuous outcomes
were: (I) Mean change in variable x, from baseline to follow up; (II) Standard deviation (SD)
of the mean difference in variable x; (III) Number in each comparison group (n) at post
intervention moment. To calculate the mean change in a variable from baseline to follow up
was used: Mean difference = mean at follow up minus mean at baseline. The same process
was used to calculate the mean difference in the experimental and control group. When the
SD values of the mean difference was not reported, the authors were contact through email
and asked for more information. After unsuccessful attempts, the variance of all articles was
estimated on the basis of the information available. For this purpose, the following equation
was used to calculate the SD difference when the SD was presented for comparing groups at
baseline and follow up.
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Standard error (SE) difference = √ [SD1 2/n1 + SD2 2/n2]; where: SD1 is the SD at
baseline; n1 is the number at follow up; SD2 is the SD at follow up; n2 is the number at
baseline.
To calculate the SD difference from the SE difference: SE = SD √n. So: SD difference
= SE difference X. If the means and SD of the outcome measures were not listed in a table or
mentioned in the text, the data were extracted from their plots using Adobe Photoshop v.
17.020.
In cases of the presence of statistical heterogeneity (Chi-squared method set at
p<0.05) across analysis, we checked the results using only random-effects mode. The
heterogeneity of the studies was also assessed by the statistic I2 and 95% CI. The statistical
analysis was performed using the Review Manager software version 5.321.
Results
The search strategy identified 93 studies. Following screening procedures, 19 studies
were found to be relevant. Ten (10) studies were excluded after reviewing their abstracts
and/or full text based on inclusion criteria. Finally, 5 studies met the inclusion criteria and
were included (summarized in Table 1). Figure 1 presents the flowchart of selection process
based on study criteria and Table 2 presents the results of PEDro scale. The methodological
quality of the included studies varied from 5 to 6 points on the PEDro scale. Three studies
scored 6 points and other two scored 5 points.
Study and subjects Characteristics
The included studies were published between 2006-2012 and were RCTs aiming to
investigate the effectiveness of ERE on muscle strength and/or functional performance. The
experimental design of the studies presented: (I) only one comparison group using another
overload device (body blade and weight machines)22,23; (II) studies with two comparison
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
groups: overload device (water devices, weight machines, free weights) and no
intervention24–26.
The included studies enrolled a total of 229 participants, with an average age ranging
from 21-54 years. The sample size ranged from 40 to 62 participants and the number of
participants per group ranged from 10 to 21 individuals. Only one study included men and
women allocated in the same group, with a sample of 40 participants22. The other four studies
were performed only with women, totaling 189 participants23–26.
In all studies, individuals were identified as "healthy" because they were functionally
independent; free of orthopedic disabilities and without comorbidities.
Training and tests characteristics
To measure the muscle strength, the following body regions and parameters were
used: (I) MVIC of upper limbs using a isokinetic dynamometer on internal and external
shoulder rotation22 and a load cell in MVIC on vertical rowing26; (II) MVIC of lower limbs
using a load cell on squat26; (III) MVIC of trunk using a load cell on back extension26.
To measure the functional performance, the following body regions and parameters
were used: (I) upper limbs using the number of repetitions on knee push-up test23–25; (II)
lower limbs using the number of repetitions on squat test23–25; (III) trunk using the number of
repetitions on crunch abdominal test24,25.
The duration of the intervention ranged from 8 to 24 weeks with a frequency of 2 to 4
times per week. The number of exercises ranged from 6 to 15 exercises, the number of sets
and repetitions per exercise was (I) 3 sets of 10-20 repetitions (2 exercises)22; (II) one set of
20 maximum repetitions (10 exercises)23; (III) one set of 20-30 maximum repetitions (10
exercises)24; (IV) one set of 8-15 maximum repetitions (15 exercises)26; (V) one set of 20
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
maximum repetitions (12 exercises)25. The rest interval between exercises in the included
studies ranged from 30s to 90s.
ERE versus passive control group
The mean strength gain observed in ERE group was greater when compared to
passive control group on function performance (MD = 7.34 repetitions; 95% CI: 5.17 to 9.51;
Z = 6.63; P < 0.00001). All subgroups analysis showed the same direction of significant
effect in favor of the ERE: (I) knee push up test (MD = 6.1 repetitions; 95% CI: 2.98 to 9.26;
Z = 3.38; P = 0.0001), squat test (MD = 7.4 repetitions; 95% CI: 4.03 to 11.06; Z = 4.21; P <
0.0001) and abdominal test (MD = 10.9 repetitions; 95% CI: 5.17 to 16.78; Z = 3.70; P =
0.0002). The general and subgroups analysis are show in Figure 2.
The mean strength gain observed in the ERE group was greater when compared to
passive control group on direct measure of muscle strength (MD = 1.89 Kg; 95% CI: 0.44 to
3.45; Z = 2.55; P = 0.01). Two subgroups analysis showed the same direction of significant
effects in favor of the ERE: MVIC lower limb (MD = 15.25 Kg; 95% CI: 7.14 to 23.38; Z =
3.68; P = 0.0002) and MVIC trunk (MD = 1.89 Kg; 95% CI: 0.44 to 3.35; Z = 2.35; P =
0.01). The MVIC upper limb subgroup analysis showed no differences between ERE and
passive group (MD = 1.07 Kg in favors to ERE; 95% CI: 0.19 to 2.34; Z = 1.66; P = 0.10).
The general and subgroups analysis are presented in the Figure 3.
ERE versus active control
The mean strength gain observed in active control groups (other methods of training)
was greater when compared to ERE on functional performance (MD = 3.1 repetitions; 95%
CI: 5.27 to 0.93; Z = 2.79; P = 0.005). Two subgroups analysis showed the same direction of
significant effects in favors to active control: knee push up test (MD = 5.1 repetitions; 95%
CI: 7.57 to 2.80; Z = 4.26; P < 0.0001) and abdominal test (MD = 3.7 repetitions; 95% CI:
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
6.20 to 1.32; Z = 3.02; P = 0.003). The squat test subgroup analysis showed no differences
between active control and ERE (MD = 1.0 repetitions in favors to active control; 95% CI:
3.79 to 1.60; Z = 0.79; P = 0.43). The general and subgroups analysis are presented in the
Figure 4.
Regarding comparisons between ERE and active control groups on muscle strength,
there were no statistical differences on mean strength gain (MD = 0.11 Kg in favor to ERE;
95% CI: 0.29 to 0.51; Z = 0.54; P = 0.59). Two subgroups analysis showed the same results
of absence in-group differences: MVIC upper limb (MD = 0.12 Kg in favors to ERE; 95%
CI: 0.28 to 0.52; Z = 0.61; P = 0.54) and MVIC trunk (MD = 0.46 Kg; 95% CI: 3.17 to 4.09;
Z = 0.25; P = 0.80). The MVIC lower limb subgroup analysis showed that mean strength gain
observed in active control group was greater when compared to ERE group (MD = 9 Kg;
95% CI: 17.89 to 0.11; Z = 1.99; P = 0.05). The general and subgroups analysis are presented
in Figure 5.
Heterogeneity
In the present review, four forest plots that report the I2 statistic (total [95% CI]) due
the heterogeneity of the continuous data were compiled. Two analyses presented no evidence
of heterogeneity (I2 = 0%): (I) ERE versus passive control on functional performance; (II)
ERE versus active control on muscle strength.
Two analyses presented high evidence of heterogeneity: (I) ERE versus active group
on functional performance (I2 = 89%); (II) ERE versus passive control on muscle strength (I2
= 85%) in the ERE versus passive control direct measures.
Discussion
The objective of the present systematic review was to summarize the effectiveness of
elastic resistance exercise on muscle strength and functional performance in healthy adults.
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
To the best of our knowledge, the meta-analysis procedure applied in this study was the first
to identify the isolated effects of ERE on different outcomes across different body regions.
The analysis showed that the effects of ERE were superior when compared to passive control
for functional performance and muscle strength. However, when compared to active controls,
the effect was inferior on function performance and similar on muscle strength.
Overall, our results demonstrated that ERE was more effective when compared to
passive control for functional outcomes. These results were demonstrated across all of three
subgroups analysis (upper limb, lower limb and trunk), with the major results from the
abdominal crunch test (10.9 repetitions). These results were provided from three studies23–25,
all with female participants, using similar exercises and with identical methods in order to
equalize de intensity of elastic exercises. The effects of ERE on functional outcomes were
more expressive in 24 weeks24 than in 10 weeks23,25. There was no heterogeneity between
these comparisons according to the I2 statistics.
Considering the muscle strength outcome, the ERE was more effective when
compared to passive control. This result could be attributed to two subgroups analysis (lower
limbs and trunk), with the major results from MVIC of lower limbs (15.2 Kg). However, for
these subgroups, only one study was included in the meta-analysis26. In contrast, the similar
results between ERE and passive control on MVIC upper limb subgroup were provided from
two studies, and only one with women’s26 and other with men’s and women’s22. Only the
study of Colado et al.26 presented significant strength gains, which was provided by an 8-
week exercise program for major muscles of shoulder and scapular girdle (inclined standing
rowing, horizontal bench press, military press, vertical rowing, lateral raise, horizontal
abduction, biceps curl and horizontal French press). Besides, Sugimoto et al.22 employed 8-
weeks training and adopted 2 exercises (internal and external shoulder rotation), it is possible
to assume that the 8-weeks program (very short-term) associated to a low number of
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
exercises (low volume of training) determined a worst neuromuscular adaptation and could
explain the negative results of Sugimoto et al.22 on upper limb subgroup analysis (Figure 3).
The I2 statistics demonstrated high evidence of heterogeneity on these comparisons.
Similar results were demonstrated in a systematic review conducted by Martins et al.13 when
compared the effects of ERE versus passive control groups on muscle strength in older
adults. The resistance training with elastic bands showed a large effect on muscle strength in
healthy elderly (SMD = 1.30; 95% CI, 0.90, 1.71) and in participants with some functional
incapacity (SMD = 1.01; 95% CI, 0.82, 1.19), and a moderate effect on muscle strength in
elderly patients with pathology (SMD = 0.54; 95% CI, 0.12, 0.96), according to Cohen´s
classification for Effects Sizes (ESs; < 0.41 = small; 0.41 – 0.70 = moderate; > 0.70 =
large)27. In this systematic review13 the duration of the training ranged from 6 to 24 weeks at
a frequency of 1 to 5 times per week. The number varied from 2 exercises to 11, the number
of sets per exercise ranged from 1 to 3 and number of repetitions varied between 10 and 12.
The American College of Sports Medicine´s Position Stand reports that a participant
in regular physical activity elicits a number of favorable responses that contributes to
health28,29. Corroborating to this statement, several systematic reviews performed
comparisons between physical exercise and no interventions or usual care, and evidence
indicates that physical exercise is strongly recommended for different population30–35. The
results from RCT´s and systematic reviews showing that exercises are more effective than no
intervention or usual care groups are useful for sedentary individuals that chose to begin
resistance training programs using new approach and devices, and for test the safety (e.g.
adverse events) to the respective intervention.
The overall results in favor of the active control groups when compared to ERE on
functional outcomes could be particularly attributed t two subgroups analysis (knee push up
and abdominal crunch test), with the major results from the knee push up test (5.1
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
repetitions). These results were provided by three studies23–25 that used weight machines and
aquatic devices that increased the drag force and imposed an external overload. In this
context, Colado et al.25, was the last RCT published that recommended the use of elastic
bands as a short term and cost-effective alternative to the use of weight machines, as no
significant differences between the two devices exists in terms of their effects on physical
capacity. However, our findings demonstrated that only one subgroup analysis (squat test)
had similar effects when comparing weight machines and aquatic devices versus ERE on
functional outcomes. The overall result in favour of the active control groups compared to
ERE on functional outcomes was unexpected. Allied health professionals recognize
advantages arising from elastic resistance during the performance of functional exercises.
Thus, theoretically, elastic devices could provide better results on functional performance,
tough our results did not confirmed this hypothesis. With respect to the methodology of the
articles included on meta-analysis procedures (Figure 4), the authors did not employed
functional exercises. This could partially explain our results. The I2 statistics demonstrated
high evidence of heterogeneity.
Regarding muscle strength outcome, the similar results between ERE and active
control groups could be attributed to two subgroups analysis (MVIC of upper limb and
trunk). These results were provided by two studies22,26 that used weight machines and flexible
shoulder devices as external overload. Only one subgroup analysis showed superior effects in
favour of the active control, which was the MVIC of lower limbs (9 Kg). Colado et. al26
reported that resistance training using elastic tubing or weight machines/free weights
provided equivalent improvements in the isometric force after short-term programs applied in
physically active young women. However, our findings demonstrated that only two subgroup
analysis (MVIC of upper limb and trunk) had similar effects when comparing weight
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
machines/free weights versus ERE on muscle strength. There was no heterogeneity between
these comparisons according to the I2 statistics.
Soria et al.18 compared the effects of traditional versus variable resistance training on
the adaptive response produced in terms of maximal strength. The results indicated that
variable resistance training over at last 7 weeks could lead to a significantly greater strength
gain (1RM) compared to traditional strength training programs. However, a subgroup
analysis based on the training status demonstrated a greater strength gain with variable
resistance training than the traditional training and the strength gains observed for the non-
trained did not vary significantly. These results could not be directly compared with the
present study, as there was a methodological heterogeneity regarding the adopted maximal
strength tests (1RM versus MVIC), studies designs (variable resistance training using chains
or elastic bands attached to the barbell in bench press or back squat exercise versus elastic
resistance training performed as isolated method) and participants training status (untrained,
with under 12 months experience in strength training versus no previously experience in a
program of strength training). Moreover, muscle strength findings were similar between
studies, where the strength gains observed for the non-trained adults undertaking a variable
resistance training program versus a traditional program did not vary significantly17.
There is a growing interest in effective training methods suitable for different contexts
(such as workplace, hospitals, home, training field) 36. Accordingly, resistance exercise using
elastic bands has shown to be equally effective in activating smaller muscles in the neck,
shoulder, and arms when compared to similar training exercises performed dynamically with
dumbbells37,38. Jacobsen et al.39 demonstrated that in untrained individuals, knee extensions
performed with elastic tubes induced similar electromyographic activity patterns compared to
exercise performed in machines. Andersen et al.40 also demonstrated higher levels of muscle
activation during resistance exercises with dumbbells and elastic tubing, indicating that
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
therapists can choose either method in the clinical practice. According to this, was expected
that the ERE would lead to similar effects on muscle strength of healthy adults. But our
findings corroborated partially to the previous hypothesis, such as muscle strength (maximal
voluntary isometric contraction) between groups were similar and functional outcomes (knee
push up and abdominal crunch test) was not, in which results were in favors to other types of
exercises (weights machines and aquatic devices).
With respect to the methodological quality of the included studies, the absence of
assessor blinding should be attempted in future studies. Additionally, it is possible to assume
that the included studies underestimated the training loads due to the lack of elastic exercise
intensity control using parameters such as Newton, Kgf or pounds. Thus, future research
must include load control if the aim is to improve the muscle strength. The present review
may be limited by the few number of studies included in the meta-analysis and by their
methodological heterogeneity. Even tough the four forest plots included at least 2-3 of the
included studies, and in two subgroups (MCVI of lower limb and trunk) the analysis was
performed with 1 study. Thus, our findings must be interpreted with caution. Similarly, the
heterogeneity according to the I2 statistics were high in two comparisons (ERE vs active
control on functional performance and ERE vs passive control), with suspected clinical and
or methodological heterogeneity across compared studies. It is worth of note that the majority
of participants were females, thus, the external validity must be addressed to this population.
It is highly recommended that future studies adopt a comparative analysis of the ERE
effectiveness as an isolated training method for adult men with more outcomes of muscle
strength and functional performance in order to elucidate the dose-response of ERE
programs.
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Conclusion
The present systematic review demonstrated that resistance exercise performed with
elastic bands is better than passive control groups for improvements in muscle strength and
functional capacity of healthy adults. Elastic resistance training seems to produce worst
results on functional outcomes, however, seems to be effective on muscle strength compared
to traditional methods of resistance exercise.
Acknowledgments
The authors thank Michal Kicinski for the assistance in the procedures of data analysis and
comments on the final draft of this manuscript.
Funding
The authors received no financial support for the research, authorship, or publication of this
article.
Trial registration: This review was registered in PROSPERO under the number:
CRD42015027002 (http://www.crd.york.ac.uk/PROSPERO/).
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic
Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Figure 1 – PRISMA flow diagram
Records identified through database
searching
(n = 208)
Screening
Included
Eligibility
Identification
Additional records identified
through other sources
(n = 2)
Records after duplicates removed
(n = 93)
Records screened
(n = 19)
Records excluded
(n = 74)
Full-text articles assessed
for eligibility
(n = 5)
Full-text articles excluded,
with reasons
(n = 10)
Studies included in
qualitative synthesis
(n = 5)
Studies included in
quantitative synthesis
(meta-analysis)
(n = 5)
Not full-text
(n = 4)
(
(n = 4)
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Table 1 - Characteristics of the studies.
Author
and year
Aim of the
study
Sample
size (n)
Age (years)
Gender
Groups
Duration
(weeks)
Frequency
Intervention
Outcome
measures
Author´s conclusion
Sugimoto,
2006
Compare
strength gains on
the shoulder
after an exercise
program using
'Bodyblade' and
exercises with
elastic bands
EG = 12
OD = 14
CG = 14
24.3 (5.0)
23.8 (5.1)
24.9 (5.2)
M = 13
F = 27
EG =
elastic band
OD =
‘Bodyblade’
CG =
without
intervention
08
Once a
week
EG =
3 x 10-20 repts
OD =
2 x 30s-60s
CG =
without
intervention
Isometric,
concentric, and
eccentric muscle
strength of the
internal and
external shoulder
rotators was
measured by a
isokinetic
dynamometer
The exercise program with
OD no increased strength in
external and internal rotators
in the CG and EG. Since the
EG obtained in isometric
strength of internal and
external rotators higher
percentage than the OD
group and CG
Colado,
2008
If a short-term
supervised
muscular
endurance
program,
produces
differences in
muscle mass and
functional
capacity when
using two
different devices
EG = 21
OD = 14
CG = 10
54.14 (2.87)
51.07 (6.81)
53.9 (1.85)
M = 0
F = 45
EG =
elastic bands
OD =
weight
machines
CG =
without
intervention
10
Twice a
week
10 combined
exercises with
20 repts in
each exercise
in all devices
Knee push-up test
to check the
resistance of the
extensor muscles
of the elbow and
shoulder
horizontal
adductor, squat
test for lower
limbs
Resistance training with
elastic bands produces
similar adaptations to the
other device used in the
study, in the early stages of
strength training
Colado,
2009
Effects of
resistance
training with
aquatic
resistance
devices or
elastic bands
on markers of
cardiovascular
health and
physical
capacity
EG = 21
OD = 15
CG = 10
54.0 (2.8)
54.7 (2.0)
52.9 (1.9)
M = 0
F = 46
EG =
elastic bands
OD =
aquatic
resistance
device
CG =
without
intervention
24
Twice per
week in
first 12
weeks and
three times
per week
for weeks
13–24
7 different
types of
routines,
progressive,
combining 8-
10 exercises
with 20-30
repts and 30s
for rest
Physical capacity
tests - sit and
reach, knee push-
up, squat and
abdominal crunch
Both exercise groups
improved physical capacity
indicators tested, but only
OD group, significantly
improved resistance of the
abdominal muscles when
compared with the group of
EG.
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“Effects of Elastic Resistance Training on Muscle Strength and Functional Performance in Healthy Adults: A Systematic Review and Meta-Analysis” by de Oliveira PA et al.
Journal of Physical Activity & Health
© 2016 Human Kinetics, Inc.
Author
and year
Aim of the
study
Sample
size (n)
Age (years)
Gender
Groups
Duration
(weeks)
Frequency
Intervention
Outcome
measures
Author´s conclusion
Colado,
2010
Effects of a short
resistance
exercise
program, on the
strength in
young women
using weight
machines and
free weight or
elastic tubing
EG = 12
OD = 11
CG = 13
21.41 (0.36)
21.73 (0.78)
22.23 (0.97)
M = 0
F = 36
EG =
elastic
tubing
OD =
weight
machine/
free weight
CG =
without
intervention
08
2 – 4
sessions
per week
15 combined
exercise in 3
different
training
sessions, with
15 repetitions
during weeks
1-2, 10 repts
weeks 3 - 4, 8
repts weeks 5 -
7, and 15 repts
in the last
week of
training and
30s - 90s for
rest, according
to the week
The maximal
isometric
voluntary
contraction in 3
different
Conditions using
load cell: vertical
rowing, squat and
back extension
The strength training
using elastic tubing or weight
machines and free weights
lead to an equivalent increase
of isometric strength in
young and
physically active women
Colado,
2012
Effects of a
supervised
strength training
program on
body
composition and
physical
capacity of
older women
using three
different devices
EG = 21
OD1 = 14
OD2 = 17
CG = 10
54.14 (0.63)
51.07 (1.82)
54.71 (0.45)
53.9 (0.59)
M = 0
F = 62
EG =
elastic bands
OD1 =
weight
machines
OD2 =
aquatic
device
CG =
without
intervention
10
Twice per
week
12 combined
exercises with
20 repts,
during the
week, with
change of
speed exercises
performed in
water and
passive rest 30s
In assessing the
physical capacity
were carried out
three tests: knee
push-up, squat
and abdominal
crunch
There are minimal
differences in the
effectiveness of the use of
OD2, EB or OD1 to
improve physical capacity
and body composition
in postmenopausal women.
The different
resources for strength
training that have been
used in this study have
shown the potential to
cause improvements in the
post-test compared to
the pre-test
EG = elastic group; OD= other device; CG=control group; M = male; F= female; repts = repetitions.
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© 2016 Human Kinetics, Inc.
Table 2 - Assessment of the methodological quality of the included studies by the PEDro scale.
First author,
year
1
Eligibility
criteria*
2
Random
allocation
3
Concealed
allocation
4
Baseline
Comparability
5
Blind
subjects
6
Blind
therapists
7
Blind
assessor
8
< 15% of
desistence
9
Intention
to treat
analysis
10
Between
groups
comparison
11
Point
estimates
and
variability
Total
Sugimoto, 2006
1
0
1
0
0
0
1
1
1
1
6
Colado, 2008
1
0
1
0
0
0
1
1
1
1
6
Colado, 2009
1
0
1
0
0
0
0
1
1
1
5
Colado, 2010
1
0
1
0
0
0
1
1
1
1
6
Colado, 2012
1
0
1
0
0
0
0
1
1
1
5
*Criterion 1 is not considered for the final score because it is an item that assesses the external validity (Maher, Sherrington, Herbert, Moseley, & Elkins, 2003).
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25
Figure 2 – ERE versus passive control on functional performance.
Forest plot of the results of the meta-analysis showing the mean difference in number of
repetitions and 95% CI detected for the Knee push up test, Squat test and Abdominal crunch
test. The last diamond represents the pooled mean difference (♦). The letters after author's
names represent different tests described by the same study.
Figure 3 - ERE versus passive control on muscle strength.
Forest plot of the results of the meta-analysis showing the mean difference in weight and 95%
CI detected for the MVIC lower limb, MVIC trunk, MVIC upper limb. The last diamond
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26
represents the pooled mean difference (♦). The letters after author's names represent different
tests described by the same study. Suguimoto 2006: (a) – isometric (65º external rotation
position) shoulder internal rotation measurement; (b) – isometric (10º internal rotation position)
shoulder internal rotation measurement; (c) – isometric (65º external rotation position)
shoulder external rotation measurement; (a) – isometric (10º external rotation position)
shoulder external rotation measurement.
Figure 4 - ERE versus active control on functional performance.
Forest plot of the results of the meta-analysis showing the mean difference in number of
repetitions and 95% CI detected for the Knee push up test, Squat test, Abdominal crunch test.
The last diamond represents the pooled mean difference (♦). The letters after author's names
represent different tests described by the same study.
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27
Figure 5 - ERE versus active control on muscle strength.
Forest plot of the results of the meta-analysis showing the mean difference in weight and 95%
CI detected for the MVIC lower limb, MVIC trunk, MVIC upper limb. The last diamond
represents the pooled mean difference (♦). The letters after author's names represent different
tests described by the same study. Suguimoto 2006: (a) – isometric (65º external rotation
position) shoulder internal rotation measurement; (b) – isometric (10º internal rotation position)
shoulder internal rotation measurement; (c) – isometric (65º external rotation position)
shoulder external rotation measurement; (a) – isometric (10º external rotation position)
shoulder external rotation measurement.
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