Pilates Dosage in Rehabilitation of Patients With Musculoskeletal Conditions: A Scoping Review

Abstract

Context:

Pilates exercise is commonly used in the rehabilitation of individuals with musculoskeletal conditions, but dosing parameters for optimal outcomes are unclear. Large variations exist in Pilates-based protocols, and research related to specific dosing is sparse.

Objective:

To identify optimal dose parameters of Pilates exercise when applied to the rehabilitation of musculoskeletal conditions.

Data Sources:

English-language articles published up to February 2023, in the PubMed, Scopus, Science Direct, and Pedro databases.

Study Selection:

Articles where patients 20–60 years old with musculoskeletal conditions received a Pilates-based exercise intervention and reported quantification of treatment dose. A total of 72 full-text articles were assessed, with 14 meeting inclusion criteria.

Study Design:

Scoping review.

Data Extraction:

Two investigators (A.P.S., G.K.) independently identified all proposed Pilates-based protocols and outcome measures from the included studies.

Results:

From the 1667 references initially found in 4 databases, 14 studies were included of which 13 were randomized controlled trials or quasi-experimental (612 patients) and 1 was a Cochrane review (19,642 patients). Eight studies were of high methodological quality. The most frequent musculoskeletal condition examined was chronic low back pain. Pilates dosage regarding total intervention duration ranged from 6 to 16 weeks, but the most frequent duration reported was 8 weeks and 2 to 3 sessions per week with sessions lasting 50 to 60 minutes.

Conclusion:

This review suggests that there are clinically relevant Pilates dosing parameters that result in improved outcomes for patients with musculoskeletal disorders.

Pilates is an increasingly popular type of exercise in rehabilitation. ⁵⁰ Originally called contrology, Pilates was designed as a low-intensity and load exercise suitable for everyone. ⁸ Centering, breathing, control, precision, concentration, and flow are reported as the major Pilates principles, ⁵⁰ and seem to have multiple benefits on factors such as pain, functional capacity, and quality of life (QOL) ¹⁵ .

Pilates has been widely used in recent years as a therapeutic approach in various injuries and conditions such as multiple sclerosis, ³⁰ hip fractures, ⁴⁷ patellofemoral pain syndrome, ⁵ and Parkinson’s disease. ⁴⁸ However, the major research interest regarding the effectiveness of Pilates is focused on musculoskeletal conditions.^6,13,15,51 Musculoskeletal conditions have high prevalence and are highly costly to primary care. ¹¹ Approximately 1.3 billion people worldwide are affected by some form of musculoskeletal disorder. ⁴¹ These conditions develop gradually, often present a chronic course, and are associated with many symptoms such as pain. Pain can gradually become worse, affecting functionality, ability to perform daily activities, and QOL. ¹¹ Pilates has increased in popularity recently in rehabilitation programs for musculoskeletal disorders, such as chronic low back pain (LBP),^36,53 cervical spine pain (CSP), ¹⁴ knee osteoarthritis, ²⁶ osteoporosis, ⁴ scoliosis, ²² and ankylosing spondylitis. ³ Systematic reviews and meta-analyses have found that Pilates is effective in reducing pain and kinesiophobia and in improving function, muscle strength, and QOL.^11,16,23,54

However, it is difficult to draw safe conclusions due to significant heterogeneity between protocols used on specific conditions. In addition, no studies to date have been conducted to investigate the optimal exercise dosage in Pilates, despite its widespread application. As a consequence, Pilates as a rehabilitation tool is applied in an uncontrolled way and often lacks scientific documentation or is applied by professionals who lack specific training.^8,16 These factors highlight the need for high-methodological-quality studies by specialized health professionals who will be able to incorporate the results into a clinical setting. Finally, specific training of health professionals will set the fundamental principles for the appropriate treatment regimen and the optimal dosage on every occasion.

The aim of this study was to collect data and create a data “map” to determine the optimal exercise dosage, regarding the application of Pilates in musculoskeletal conditions and injuries based on efficiency and level of evidence.

Methods

The scoping review was chosen as the most appropriate methodology to answer this broad research question and to capture the range of information regarding the dosage of the Pilates method when applied to the rehabilitation of musculoskeletal conditions. Study design was based on the 22-item PRISMA-ScR checklist. ⁴⁹

Inclusion Criteria

In order to be included, studies had to meet a set of inclusion criteria. We used the framework proposed by Joanna Briggs (JBI) Reviewer’s Manual, which includes 3 pillars in the search process: population–design–context (population–concept– context). ³⁹

• Population: Patients 20–60 years old with musculoskeletal conditions (including musculoskeletal pain) or injuries such as tendinopathy, injuries, and tears were included. Studies with an inclusion criterion of a different age group than the above (eg, lower limit <20 years or upper limit > 60 years) were examined for the mean age of the sample (mean ± standard deviation) and if participants were not younger than 20 years or older than 60 years they were included.

• Planning: Experimental studies, both randomized controlled trials (RCTs) and non-RCTs, cohort studies, cross-sectional studies, case studies, systematic reviews, meta-analyses, and simple reviews were included. Identified study protocols were included if the full text of the study was available.

• Content: We included studies that delivered a Pilates-based exercise intervention and reported quantification of treatment dose. Dose was defined as any quantified parameter of the Pilates-based exercise intervention. In order to be included, studies had to refer to at least 1 quantitative factor from session length, session frequency, and number of repetitions. Studies were included if they were written in the English language.

Exclusion Criteria

Studies with patients with a history of surgery, patients with comorbidities (eg, neurological problems, systemic diseases, metabolic diseases, multiple sclerosis, cancer, Parkinson’s disease, osteoporosis, hypertension, and cardiac problems) were excluded, as well as patients receiving medication (including infusions). Studies conducted in healthy populations, pregnant women, and the elderly were excluded. Studies were excluded if they were dissertations, government reports, books, conference abstracts, and editorials, and when their full text was not available.

Sources of Information

PubMed, Scopus, Science Direct, and Pedro databases were searched for studies published up to February 2023. The search strategies (Appendix Table 1) were based on the following terms: (1) Pilates; (2) musculoskeletal disorders-injuries; and (3) effectiveness and dosage. The final search results were exported to Zotero.

Methodological Quality

RCTs were assessed for their methodological quality by 2 researchers (A.P.S., G.K.) using the Pedro scale. In case of disagreement, the contribution of a third researcher (D.S.) was requested. The Pedro scale evaluates 11 criteria (Appendix Table 2). A higher score indicates a higher level of methodological quality.

Results

Study Selection

Selection of studies was carried out collaboratively by the same 2 researchers, who successively evaluated the titles, abstracts, and finally the full text. Disputes were resolved by the third researcher. The initial search yielded 1667 studies. From duplicate screening, 629 studies were removed, leaving 1038 that were screened based on their title and abstract. At this stage, 966 studies were rejected and 72 remained, for which the full text was searched and studied. After implementing the inclusion/exclusion criteria, 14 studies remained which were included in the scoping review (Figure 1).

Figure 1.

PRISMA study selection flow chart.

Synthesis of Results

Of the 14 studies, 78.5% (11 studies) are RCTs,^{1,6,12,17,21,24,25,32,35,52,55} 14.5% (2 studies) are quasi-experimental and pilots,^{29, 46} and 7% (1 study) is a review. ¹⁸ Chronic LBP is the musculoskeletal condition investigated in most studies (78.5% or 11 studies).^{6,12,17,21,24,25,32,35,46,52,55} Two studies (14.5%)^1,29 examined chronic CSP, whereas 1 study (7%) investigated different conditions. ¹⁸ The studies have been conducted mainly in Europe (28.5% or 4 studies)^12,24,29,55 and Asia (21.5% or 3 studies),^6,32,52 and then in America (21.5% or 3 studies),^17,35,46 Australia (14.5% or 2 studies),^21,25 Africa (1 study or 7%), ¹ or involved a combination of regions (1 study or 7%). ¹⁸

Characteristics of Studies

A total of 612 patients have participated in 13 of the 14 studies that are RCT or quasi-experimental, whereas an additional sample of 19,642 patients have been examined by the 1 study that is a review of Cochrane reviews. ¹⁸ The 11 RCTs investigated the effectiveness of Pilates (either alone or in combination with other treatment regimens) versus other exercise interventions and/or a control group. Data from the studies are summarized in Table 1.

Table 1.

Characteristics of included studies

Author(s)Ref	Study Design	Sample	Intervention	Outcome Measures	Results
Zeada 55	RCT	20 athletes with chronic pain in lumbar spine EG: 10 CG: 10	EG: Pilates CG: no intervention	RMDQ Sorensen Test Lumbar spine flexion-extension	Improvements to the EG team only
Mallin and Murphy 29	Semiexperimental pilot study	13 patients with chronic pain in cervical spine	Pilates mat	NRPS NDI PSFS ADIT	Improvement in all outcome measures
Franco et al 17	RCT	148 patients with LBP IFC+PG: 74 P+IFC+PG: 74	IFC+PG interferential currents and Pilates P+IFC+PG: placebo, interferential currents and Pilates	Pain PPT RMDQ TSK PSFS GPS	Improvement in both groups
Hides et al 21	RCT	46 elite footballers with or without LBP G1: 17 G2: 15 G3: 14	G1: Pilates – motor control – advanced motor control – Pilates G2: Pilates – motor control – Pilates G3: Pilates – Pilates – motor control	CSA and symmetry of the multifidus muscle, quadratus lumborum muscle, iliopsoas muscle Change in trunk CSA Injuries (availability of players for competitive games) Perceived program benefit	Multifidus muscle size– improvement more in G1 and G2 Abdominal capacity- improvement more in G1 and G2 Player availability for competitive games – greater in G1 and G2 teams
Kliziene et al 24	RCT	54 patients with LBP EG: 27 CG: 27	EG: Pilates CG: no intervention	Power Static strength of trunk muscles VAS	Improvements in both groups in core strength and static endurance pain – greater improvement in EG (for 1 month post intervention)
Stieglitz et al 46	Semi-experimental pilot study	12 patients with chronic back pain (work-related)	Pilates with equipment	VAS ODIs	Improvements after the end of the intervention
Cruz-Diaz et al 12	RCT	98 patients with chronic LBP PMG: 34 PEG: 34 CG: 30	PMG: Pilates mat PEG: Pilates with equipment CG: no intervention	VAS RMDQ TrA TSK	Improvements in both intervention groups versus the control group, except for TrA at rest
Geneen et al 18	Cochrane Review of Reviews	19,642 patients with chronic pain	Many types of exercises including Pilates	Pain Functionality Psychology QOL Adherence to treatment Use of health care services Side effects Death	Interventions should last at least 8 weeks
Knox et al 25	RCT	24 patients with chronic LBP EG: 12 CG: 12	EG: Pilates CG: no intervention	Motor control (APA -CPA, RA, TA/IO, ES)	Improved motor control (TA/IO) in EG
Mazloum et al 32	RCT	47 patients with chronic LBP SP: 16 EB: 15CG: 16	SP: Pilates EB: extension exercises CG: no intervention	VAS ODIs ROM: lumbar flexion (modified Schober) Lumbar curvature	Improvement in both groups, greater in the SP group
Miranda et al 35	RCT	28 patients with chronic LBP PM: 2 PS: 14	PM: Pilates mobility PS: Pilates stability	ODIs VAS FMS	Improvement in both groups
Yalfani et al 52	RCT	24 patients with chronic LBP MPG WPG	MPG: mat Pilates WPG: water Pilates	VAS ODQ BBS	Improvement in both groups, except for dynamic balance
Akodu et al 1	RCT	45 patients with chronic pain in cervical spine NSE: 17 PE: 14 DIE:14	NSE PE: Pilates DIE	NPRS-11 ISI TSKNDI	Improvement in all outcomes, in all groups over time NSE exercises: statistically significant improvement in pain compared with PE
Batibay et al 6	RCT	53 patients with chronic LBP G1: 28 G2: 25	G1: mat Pilates G2: conventional exercise at home	VAS ODIs QDSBDS SF-36 MST Sit-and-reach test Sit-up test	Improvement in both groups

ADIT, abdominal drawing in test; APA, anticipatory postural adjustments; BBS, Berg Balance Test; BDS, Beck Depression Questionnaire; CG, control group; CPA, compensatory postural adjustments; CSA, cross sectional area; DIE, dynamic isometric exercise; EB, extension-based; EG, experimental group; ES, erector spinae; FMS, functional movement scale; G1, group 1; G2, group 2; G3, group 3; IFC, interferential current; IO, internal oblique; ISI, insomnia severity index; LBP, low back pain; MST, Modified Schöber Test; NDI, Neck Disability Index; NRPS, Numerical Rating Pain Scale; NSE, neck stabilization exercise; ODI, Oswestry Disability Index; ODQ, Oswestry Disability Questionnaire; PG, Pilates group; PE, Pilates exercises; PEG, Pilates with equipment group; PM, Pilates mobility; PMG, Pilates mat group; PPT, handheld pressure algometer; PS, Pilates stability; PSFS, Patient Specific Functional Scale; QDS, Qubec Disability Index; QOL, quality of life; RA, rectus abdominus; RCT, randomized controlled trial; RMDQ, Roland Moris Disability Questionnaire; ROM, range of movement; SF-36, Short-form health survey; SP, selective Pilates; TA, transvere absominis; TrA, transversus abdominus; TSK, Tampa Scale of Kinesiophobia; VAS, visual analog scale.

Methodological Quality

Eight out of 12 studies gathered scores >7 and are thus considered of high methodological quality.^{1,6,12,17,32,35,52,55} The remaining 3 studies scored 6 points each and are classified as moderate methodological quality^21,24,25 (Table 2).

Table 2.

Results of evaluation of the methodological quality of the studies

Studies	Criteria
	1	2	3	4	5	6	7	8	9	10	11	Score
Hides et al 21	No	Yes	No	Yes	No	No	Yes	Yes	Yes	Yes	No	6
Zeada 55	Yes	Yes	Yes	Yes	No	No	No	Yes	Yes	Yes	Yes	8
Franco et al 17	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes	Yes	10
Kliziene et al 24	Yes	No	No	Yes	No	No	No	Yes	Yes	Yes	Yes	6
Cruz-Diaz et al 12	Yes	Yes	Yes	Yes	No	No	Yes	Yes	Yes	Yes	Yes	9
Knox et al 25	Yes	No	No	Yes	No	No	Yes	Yes	No	Yes	Yes	6
Mazloum et al 32	Yes	Yes	No	Yes	Yes	No	No	Yes	Yes	Yes	Yes	8
Miranda et al 35	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	No	No	8
Yalfaniet al 52	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	No	Yes	Yes	9
Akodu et al 1	Yes	Yes	No	Yes	Yes	No	Yes	No	Yes	Yes	Yes	8
Batibay et al 6	Yes	Yes	No	Yes	No	No	Yes	Yes	Yes	Yes	Yes	8

1= eligibility criteria; 2 = random allocation; 3 = allocation concealment; 4 = similarity of groups at baseline; 5 = blinding of subjects; 6 = blinding of therapists; 7 = blinding of assessors; 8 = adequate follow-up; 9 = intention-to-treat analysis; 10 = comparisons between groups; 11 = point measures and measures of variability outcome measures.

Among 11 studies that evaluated Pilates in chronic LBP the most frequently evaluated outcome measures were functional capacity and pain. Kinesiophobia was assessed in 3 studies^1,12,17 with the Tampa Scale of Kinesiophobia (TSK). In the review by Geneen et al, ¹⁸ the primary outcome measure assessed was self-reported pain.

Pilates Dosage

Pilates dosage was reported in 13 studies and ranged from 6 to 16 weeks. In all 13 RCTs and quasiexperimental studies, the number of sessions per week was reported. In 5 studies, there were 3 sessions per week,^{6,17,25,32,52} whereas in 6 studies 2 sessions were performed per week.^{1,12,21,24,35,46} In only 1 study, there were 4 sessions per week. ⁵⁵ The duration of each Pilates session was reported in 11 of the 13 RCTs and quasiexperimental studies. In 3 studies the duration was 60 minutes,^6,24,29 in 3 studies it was 50 minutes,^12,35,46 and in 1 study it was 50 to 60 minutes. ²⁵ The repetitions of each exercise in the Pilates program were reported in only 3 of the 13 RCTs and quasiexperimental studies. In 3 of them, there were 10 repetitions,^1,6,17 whereas in 1 study 8 repetitions were done. ²⁴ Dosing data for Pilates programs are summarized in Table 3.

Table 3.

Dose characteristics of Pilates programs

Author(s)Ref	Intervention Duration, weeks	Sessions per Week	Session Duration, min	Repetitions
Zeada 55 (8/12)	8	4	-	-
Hides et al 21 (6/12)	G1:15, G2:8, G3:7	2	30	-
Mallin and Murphy 29	6	1	60	10-15 mat exercises
Franco et al 17 (10/12)	6	3	40	10
Kliziene et al 24 (6/12)	16	2	60	8
Stieglitz et al 46	6	2	50	8 exercises (STOTT PILATES)
Cruz-Diaz et al 12 (9/12)	12	2	50	-
Geneen et al 18	8	-	-	-
Knox et al 25 (6/12)	8	3	50-60	8 sections of exercises
Mazloum et al 32 (8/12)	6	3	-	-
Miranda et al 35 (8/12)	(10 sessions)	2	50	12 exercises
Yalfaniet al 52 (9/12)	8	3	75	14 exercises
Akodu et al 1 (8/12)	8	2	30	10
Batibay et al 6 (8/12)	8	3	60	10

^aWithout reference to repetitions.

Discussion

This scoping review aimed to determine the optimal exercise dosage, regarding the application of Pilates in musculoskeletal conditions and injury rehabilitation. Although existing research shows that Pilates can be effective, it is not officially included or taught as a rehabilitation method.^8,51 Pilates is integrated into rehabilitation programs by clinicians without proper training, while there is a lack of relevant certifications for physical therapists^13,16 with few exceptions.^13,53 In this context, the present study tried to investigate the optimal dosage in terms of session frequency, repetitions, and duration of Pilates exercises in musculoskeletal conditions and injuries. A total of 72% of studies demonstrated a high level of research evidence and 28% demonstrated a moderate level of research evidence. From the included studies, we reached conclusions regarding the conditions/injuries, interventions, and outcome measures. Eight weeks was the most frequently occurring duration of intervention, the most frequent frequency of sessions was 2 to 3 per week, and the most frequent duration was 50 to 60 minutes while the number of repetitions shows significant variability. Nevertheless, the most commonly suggested number of repetitions by the researchers in high-quality studies was 10. In the literature, few studies have investigated the optimal exercise dosage for Pilates in musculoskeletal conditions. One RCT ³⁶ investigated the effectiveness of Pilates on pain and disability, in 3 different treatment arms: 1, 2, or 3 sessions per week. Compared with a control group, which only received advice via a leaflet, all treatment groups had statistically significant improvements in pain and disability. Yet, the group that received 3 sessions per week did no better than the group that received 2 sessions per week in the short term. Another study was based on the Delphi method and was conducted among 30 physiotherapists/Pilates therapists, in order to reach a consensus on the application of this form of exercise in the treatment of patients with chronic LBP. Physiotherapists recommended that Pilates should be done twice a week for 3 to 6 months. ⁵⁰ A mixed methodology study investigated how Pilates is applied to musculoskeletal conditions. ¹³ Most physiotherapists conducted more than 1 Pilates class per week and modified the exercises according to patients’ needs. They advocated individual, personalized exercise programs for optimal recovery, as well as health benefits such as reduced kinesiophobia, improved body awareness, and muscle strength. These results are consistent with the findings of the present study.

Another important finding is that scientific research around Pilates and its use in rehabilitation has focused to a greater extent on musculoskeletal disorders associated with various conditions such as LBP, osteoporosis, Parkinson’s disease, multiple sclerosis, ankylosing spondylitis, hypertension, chronic CSP, and the prevention of falls in the elderly.^8,11,37,38 The study of Pilates in the rehabilitation of sports injuries is particularly limited.

Another key finding is that Pilates has been studied primarily in the treatment of pain associated with spine musculoskeletal conditions as shown by the number of studies included in this study. No RCTs have investigated whether Pilates could be effective as a conservative treatment for musculoskeletal conditions such as tendinopathy. Tendinopathy is a term used to describe a range of changes that occur in tendons, leading to pain and reduced functional capacity. ⁹ Despite the extensive research, there is no agreement regarding etiology, pathophysiology, the relationship between the pathology and the clinical appearance while there is high prevalence not only in the athletic but also in the general population. In that context, various treatments are supported but do not have satisfactory outcomes in all types of patients with tendinopathies. Tendons require the ability to withstand loads, storing energy, and then providing significant strength to perform daily activities. In most cases, the injury is related to overuse, resulting in multiple overlapping pathological processes, which lead to pain, diffuse or localized swelling, loss of tissue integrity, and reduced performance. ³⁴ Exercise-based rehabilitation of tendon pain and dysfunction are the most evidence-based intervention in the management of tendinopathy.^9,28 Eccentric exercise has dominated rehabilitation protocols for 2 decades, following Alfredson et al’s highly cited protocol ² for Achilles tendinopathy (AT). However, other types of exercise have also demonstrated a satisfactory level of efficacy, such as the combination of eccentric and concentric exercise, ²⁰ high-resistance exercises performed at a low pace, ⁷ and isotonic and isometric exercises. ³¹ Dosing of programs varies, and little is known about the optimal exercise dosage required to accelerate recovery in tendinopathy. In any case, the number of repetitions may affect the tendon’s environment, healing, and therefore tendon remodeling and the clinical effectiveness of eccentric exercise programs in AT. ¹⁹ For example, Alfredson et al’s protocol ² involves 6 sets of eccentric exercise, each consisting of 15 repetitions, twice daily for 12 weeks.

However, subsequent studies that have evaluated the effectiveness of eccentric exercise in AT have used fewer repetitions, particularly during the initial weeks of the rehabilitation program.^40,42 In addition, this approach conflicts with other studies that have found that the tendon takes up to 72 hours to achieve net collagen synthesis after heavy loading. Therefore, the above widely accepted protocol may provide an inappropriate dose of mechanical stimulus and therefore may not have positive treatment effects ⁴³ especially in an older or nonathlete population.

While the type and dose of exercise are important in achieving optimal AT rehabilitation, clinically there is a tendency, possibly incorrectly, to apply the principle that 1 type of exercise and a specific dosage fit all cases of AT patients. The fact that different eccentric exercise dosing approaches deviating from the Alfredson et al protocol have positive results as well as the fact that in addition to eccentric exercise, other types of exercise are equally effective leaves a “margin” for further research.^{7,10,20,23,27,33,44,45} Although it appears that there is no solid evidence to support the idea that eccentric exercise is more effective than concentric exercise or other types of exercise, it also remains unclear which parameters of exercise (eg, load, speed, repetitions, frequency of execution, duration of intervention) should be used to achieve significant structural changes and clinical improvements in AT patients. Alternative exercise approaches have not been studied to date. Hence, it is unclear the appropriate dosage that would make them effective. This is likely a reflection of clinical practice where there is strong emphasis on eccentric exercise programs. It is important to study alternative types of exercise in tendinopathy rehabilitation, such as Pilates, based on the dosage regimen suggested by this scoping review.

Limitations

Regarding the limitations that arise by further analyzing the results of the present review, it is essential to point out that all studies concern spinal conditions. Another limitation is that the sample consists of a greater number of women. In addition, the interventions were quite different in the types of exercises and the dosages. Finally, apart from pain and functional capacity, the applied outcome measures were quite different between studies, which make it difficult to synthesize and draw conclusions.

Conclusion

The increasing application of Pilates in rehabilitation makes it necessary to conduct well-designed studies of high level of evidence in the field. Accordingly, safe conclusions could be drawn regarding the most appropriate choice of therapeutic regimens depending on the condition as well as the optimal dosage in terms of frequency, duration, and number of repetitions. The present scoping review supports an optimal intervention duration of 8 weeks, with a frequency of twice a week, a session duration of 60 minutes, and a regimen in each applied exercise of 10 repetitions. Finally, it is argued that future studies with high methodological quality will set the principles of applying the Pilates concept in a wider range of conditions and injuries as well as in different groups of patients.