PHYSIOTHERAPY AND REHABILITATION. FISIOTERAPIA E REABILITAÇÃO

terça-feira, 21 de julho de 2015

Reliability of Electromagnetic Tracking of Scapular Orientation and Position in Healthy Sendentary Individuals

Reliability of Electromagnetic Tracking of Scapular Orientation and Position in Healthy Sendentary Individuals

Confiabilidade da Avaliação da Orientação e Posição de Repouso da Escápula de Indivíduos Saudáveis e Sedentários com o Sistema Eletromagnético de Aquisição de Dados

Camila Choqueta Biazotto ¹ , Paula Maria Ferreira Camarini ¹ , Helga Tatiana Tucci ² , Kevin James McQuade ³ , Anamaria Siriani de Oliveira ¹

¹University of São Paulo. School of Medicine of Ribeirão Preto. Department of Physiotherapy. Ribeirão Preto, SP. Brazil.

²Federal University of São Paulo. Department of Human Movement Science. Santos, SP. Brazil

³University of Washington. Division of Physical Therapy. School of Medicine. Seattle, WA. USA.

ABSTRACT

Electromagnetic systems for motion analysis are claimed as a precise technique for tracking position and orientation of human body segments. To date, reliability electromagnetic tracking was described only for the dynamic assessment of the scapula motion, and no reliability studies on its resting posture or positioning were found. The aim of this study was to analyze intra- and inter-session reliabilities and absolute errors of the scapular orientation and position at habitual resting posture in healthy individuals. Twenty-two shoulder symptom-free individuals non participants in professional or recreational sports activities involving upper extremities were volunteers in this study. The equipment used was 3SPACE Liberty system (Polhemus Inc.). The same examiner collected the kinematic data from subjects in two different sessions, with an interval from seven to ten days. Intraclass Correlation Coefficient (ICC_2,1 and ICC_{2, k}) and Standard Error of Measurement (SEM) were calculated. Inter-session reliability ranged from good to excellent (ICC from 0.66 to 0.96) and intra-session reliability was excellent (ICC ≥ 0.97). SEM values found for linear distances were smaller than 0.02 cm and scapular rotations ranged from 0.72° to 5.48°. Results of this study demonstrated that electromagnetic data acquisition of scapula habitual posture is a reliable tool for defining scapular position and orientation in sedentary shoulder symptom-free individuals.

Key words: Biomechanics; Physical therapy; Posture; Reproducibility of results; Shoulder

RESUMO

Sistemas eletromagnéticos para análise de movimento são conhecidos como precisos para registrar a posição e orientação dos segmentos do corpo humano. Até o momento, a confiabilidade do registro eletromagnético foi descrita apenas para a dinâmica da escápula, não sendo encontrados estudos de confiabilidade da posição de repouso ou postura da mesma. O objetivo deste estudo foi a análise da confiabilidade intra- e inter-sessão e erros absolutos do registro eletromagnético da posição e orientação da escápula na postura habitual de repouso de indivíduos saudáveis. Foram voluntários no estudo 22 indivíduos sem sintomas no complexo articular do ombro e não-praticantes amadores ou profissionais de esporte e atividade física envolvendo os membros superiores. O equipamento utilizado foi o sistema 3SPACE Liberty (Polhemus Inc.). Um mesmo avaliador coletou os dados cinemáticos em duas sessões diferentes com um intervalo de sete a dez dias. O Coeficiente de Correlação Intraclasse (ICC_2,1 e ICC_2,k) e o Erro Padrão de Medida (EPM) foram calculados. A confiabilidade inter-sessão variou entre boa a excelente (ICC de 0,66 a 0,96) e a confiabilidade intra-sessão foi sempre excelente (ICC ≥ 0,97). Os valores de EPM encontrados para as distâncias lineares foram menores que 0,02 cm e para as rotações da escápula relativa ao tórax variaram entre 0,72 º e 5,48 º. Os resultados deste estudo demonstraram que o registro eletromagnético da posição habitual de repouso da escápula é confiável para determinar a posição e a orientação da mesma em um população sedentária e sem sintomas no complexo articular do ombro.

Palavras-Chave: Biomecânica ; Fisioterapia; Ombro; Postura; Reprodutibilidade dos testes

INTRODUCTION

Assessment of scapular positioning is a theme has been emphasized in scientific literature⁽ ¹ ^- ¹¹ ⁾. Positioning and orientation of the scapula on thorax are important to centralize the humeral head and base for normal function of shoulder joint complex during daily and sport activities⁽ ⁵ ^- ⁷ ^, ⁹ ⁾. Resting scapular position may be influenced by thorax shape, muscle activity and anatomic variations of acromioclavicular joint⁽ ⁷ ^, ⁹ ^, ¹³ ⁾. Moreover, many muscles are inserted on scapula and therefore its resting position influences the length-tension relationship and the efficiency of these muscles^,( ⁷ ^, ¹² ⁾.

Three-dimensional systems have already been used in several studies to determine scapular position and rotation⁽ ¹ ^, ¹ ^3, ¹⁴ ⁾. Among them, electromagnetic system for tracking of human movement allows noninvasive, three-dimension, extensive and detailed analysis of the position and movement of body segments⁽¹⁵⁾.

Electromagnetic systems are subject to decreased reliability of data collected due to interference in the electromagnetic field by metals and movement between sensors and the skin⁽ ¹⁶ ^, ¹⁷ ⁾. In addition to the sources of error related to instrumental unreliability, examiner's errors and data entry errors may also occur. This is because the examiner should fix the sensors in the body of the volunteer, palpate pre-determined anatomical structures and by placing another sensor fixed to a pen (stylus) on these structures, informs these data to the system to create the orthogonal axes and determine local coordinate systems of each segment studied. Thus, any variation in the stages of constructing the local coordinate system can interfere with data reliability. Training and understanding of examiner in relation to equipment, creation of local coordinate systems and data collection reduces measurement errors.

In scientific literature review, studies assessing the reliability of electromagnetic system for acquisition of scapular kinematics during arm movements were found⁽ ⁶ ^, ¹⁰ ^, ¹⁵ ⁾. However, to date, no reliability data to assess resting scapular position with this system were found. Determining the reliability of a system that allows three-dimensional detailed analysis of scapular position and orientation is important to ensure consistency of measures and quality of future clinical trials for the treatment of different shoulder diseases.

Thus, the aim of this study was to establish reliability and absolute errors of scapular position and orientation in usual resting position of sedentary and healthy subjects using an electromagnetic tracking system.

METHODOLOGICAL PROCEDURES

Overall, 24 volunteers were recruited in the campus of the University of São Paulo, Ribeirão Preto. The volunteers of both sexes should be in good health condition and age between 18 and 40 years. This age range was chosen to ensure full bone development and to prevent age-related degenerative alterations⁽³⁾.

Presence or history of pain or any dysfunctions of upper limbs with medical diagnosis, trauma or surgery on shoulder, cervical spine or thoracic spine and participation in physical activity or sport (amateur or professional) that primarily use upper limbs were among exclusion criteria. One participant was excluded from the study after kinetic-functional evaluation due to the presence of history of trauma and clavicle fracture and one participant quit participation due to unavailability of time for second review.

Final sample consisted of twelve female and ten male participants. Twenty volunteers showed dominance of right arm and two of left arm. The mean age was 23 years (± 2.8), mean height was 170 cm (± 0.07) and mean weight was 63.1 kg (± 16.5).

The experimental study protocol was reviewed and approved by the Ethics Research Committee of the Hospital das Clínicas, School of Medicine of Ribeirão Preto, University of São Paulo - HCFMRP - USP. All participants read and signed the informed consent before inclusion in the study.

Evaluation system used was 3SPACE Liberty (Polhemus Inc.). The system consists of passive sensors and an electromagnetic field transmitter. This system is used to collect positioning and orientation data of body segments through sensors fixed to segments to be studied, which allow three-dimensional positional reconstruction of segments and human movements⁽²⁾.

Five sensors were fixed with adhesive tape to the skin of volunteers on scapula, thorax and arms bilaterally. The scapula sensor was fixed on the acromion, the thorax sensor was fixed on manubrium of the sternum and the sensor on the arms near the insertion of the deltoid muscle. In addition to the adhesive tape, sensors fixed to the arms were wrapped with elastic strip to aid fixation. Determination of local coordinate system was performed according to recommendations for upper limbs of International Society of Biomechanics (ISB)⁽¹⁸⁾. Location of anatomical structures transverse processes of T3 and T7 were also included for analysis of resting scapular position in relation to thoracic spine.

Since the beginning of procedure until the end of data collection, the volunteer was positioned on the side and front of the transmitter so that the X axis was horizontal with positive direction forward; the Y axis was vertical with positive direction upward and the Z axis was horizontal with positive direction from left to right. Combined analysis of the local coordinate system and the coordinate system of motion sensors allowed the three-dimensional analysis of the joint position (Figure 1).

Figure 1. Local coordinate systems of trunk (Xt, Yt, Zt) and left scapula (Xe, Ye, Ze) with rotations around axes represented by arrows.

During procedure for determining the position of anatomical structures and creation of local coordinate systems, the volunteer remained sat on a wooden box in military position with straight trunk, arms along the body and face turned to positive direction of X axis in the global coordinate system.

Data collection was performed without visual feedback with volunteer standing with face in the same direction in the rest position and instructed to remain in habitual posture with muscles as relaxed as possible. Moreover, before data acquisition, the volunteers were instructed to raising and lowering the arms, after which they should stand still with arms along the body and palms turned inside. Three sets were performed at rest, lasting five seconds each. The interval between collections was determined by the time spent to save the data.

Entire set procedure was repeated by same examiner after an interval of 7 to 10 days for inter-session reliability analysis. Three collections of each day were compared for intra-session reliability analysis and the average of collections of each day was calculated for inter-session reliability analysis. In a sequence of measures, some values may be higher or lower, so the average of these measures is the closest to the true value, being used to minimize random errors inherent to the measurement process⁽¹⁹⁾.

Scapula linear positioning at rest was analyzed in relation to the distance between the root of the scapular spine and T3 spinous process and between the inferior angle of the scapula and T7 spinous process (Figure 2). Superior-inferior, medial-lateral and anterior-posterior tilt scapular rotations were determined by Euler angles using the YX'Z'' sequence recommended by ISB⁽¹⁸⁾.

Figure 2. Anatomical reference points to determine the linear distance between the root of the scapular spine and its inferior angle and spinous process of the third (T3) and seventh (T7) thoracic vertebrae, respectively

Scapular rotation values and linear distance between scapula and thorax were processed through The Motion Monitor System(r) software (Innsport Inc.) and statistical analyses were performed using the IBM SPSS software v.16.0 (Chicago, IL, USA) and Excell program (Microsoft Corporation). Reliability statistics included Intraclass Correlation Index (ICC) and Standard Error of Measurement (SEM), as recommended for reliability studies⁽²¹⁾.

Relative reliability was quantified by ICC values, which were used to determine 95% confidence interval. ICC_2,1was used for intra-session reliability among the three collections of the same session and ICC_2,kwas used for inter-session with the mean of three collections of each session. ICC values were interpreted as poor when less than 0.40, good for values between 0.40 and 0.75, and excellent when exceeding 0.75⁽ ²⁰ ^, ²² ^, ²³ ⁾.

Absolute reliability was determined by the standard error of measurement using the following formula: SEM₉₀=1.65*SD*√(1-ICC), with standard deviation (SD) of the measure in the first assessment and ICC_2,1 and ICC_2,kderived from intra- and inter-session reliability⁽²⁰⁾.

RESULTS

Resting scapular position and orientation values are shown in Table 1. The results showed the scapular rest position with medial and upward rotation and anterior tilt. The lower and upward bone references were about 9 cm away from T3 spinous process and 10 cm of T7, respectively.

Table 1. Resting scapular position relative to the thorax in degrees (°) and linear distances in centimeters (cm)

	Dominant Mean [maximum; minimum]		Non-dominant Mean [maximum; minimum]
	Test	Retest	Test	Retest
Medial rotation (º)	31.11 [49.63;19.19]	29.11 [50.63;19.31]	25.89 [37.8;16.41]	26.07 [39.0;7.56]
Upward rotation*(º)	3.44 [25.98;-7.79]	03.40 [18.5;-8.79]	6.36 [25.98;-9.38]	05.75 [21.2;-2.13]
Anterior tilt(º)	10.71 [19.81;0.88]	10.90 [20.82;2.36]	8.47 [18.64;0.88]	8.44 [17.44;1.12]
Root of the scapular spine at T3 (cm)	9.61 [14.82;6.62]	9.86 [15.43;7.43]	9.43 [14.54;6.66]	9.28 [15.9;6.79]
Lowe angle of the scapula at T7 (cm)	10.26 [14.14;7.18]	10.06 [15.14;7.80]	10.2 [14.56;6.75]	10.18 [15.24;7.47]

* Negative values correspond to the lower rotation

Tables 2 and 3 show the ICC, CI95% and SEM values for the variables analyzed. The inter-session reliability ranged from good to excellent (0.66 ≤ ICC ≥ 0.96) and intra-session reliability has always been excellent (ICC ≥ 0.97). All ICC values were found within the 95% confidence interval. SEM values found for the linear distances were smaller than 0.02 cm. In scapular rotations, the SEM values were lower in intra-session measures (0.72º ≤ SEM ≥ 1.21º) compared with inter-session values (2.39º ≤ SEM ≥ 5.28º).

Table 2. Intraclass Correlation Coefficients (ICC), confidence intervals (CI) and inter-section Standard Error of Measurement (SEM) expressed in degrees for rotations and centimeters for linear distances of resting scapular position and orientation.

	Dominant			Non-Dominant
	ICC	CI*	SEM	ICC	CI*	SEM
Medial rotation	0.89	0.75-0.96	4.02	0.72	0.33-0.89	5.48
Upward rotation	0.92	0.81-0.97	3.24	0.77	0.46-0.91	5.19
Anterior tilt	0.89	0.75-0.96	2.39	0.8	0.53-0.92	3.65
Root of the scapular spine at T3	0.96	0.90-0.98	0.01	0.77	0.45-0.90	0.02
Lowe angle of the scapula at T7 (cm)	0.94	0.86-0.97	0.01	0.66	0.20-0.86	0.02

* α = 0.05

Table 3.Intraclass Correlation Coefficients (ICC), confidence intervals (CI) and intra-section Standard Error of Measurement (SEM) expressed in degrees for rotations and centimeters for linear distances of resting scapular position and orientation.

	Dominant			Non-Dominant
	ICC	CI*	SEM	ICC	CI*	SEM
Medial rotation	0.99	0.98-1.00	1.21	0.99	0.99-1.00	1.04
Upward rotation	0.99	0.99-1.00	1.14	0.99	0.98-1.00	1.08
Anterior tilt	0.99	0.99-1.00	0.72	0.99	0.99-1.00	0.82
Root of the scapular spine at T3	0.97	0.94-0.99	0.01	0.97	0.94-0.99	0.01
Lowe angle of the scapula at T7 (cm)	0.98	0.97-1.00	0.00	0.99	0.99-1.00	0.00

* α = 0.05

DISCUSSION

In this experiment, at least three sources of error can cause reduced reliability of the measures studied: equipment accuracy, examiner ability to palpate, mark and scan reference points for the construction of repeatable anatomical models and natural variation of scapular position, which may be affected by changes in muscle tension or climate, posture inattention and emotional stress. Nevertheless, inter-session reliability of variables related to the resting scapular position and orientation in relation to thorax in the present study ranged from good to excellent and intra-session reliability was always excellent.

Although it was not possible to compare findings of this study with those previously reported in literature, studies on the reliability of measures of the dynamic movements of shoulder with the same system also found reliability results from good to excellent and SEM values similar to those shown here⁽ ⁹ ^, ¹³ ^, ¹⁴ ⁾.

Results of this study also showed greater inter-session reliability for dominant limb compared to non-dominant limb. More functional use in daily living tasks and greater active and passive tension of muscles stabilizing the scapula of the dominant limb may be an explanation for this finding⁽²⁴⁾.

Since equipment accuracy is established by the manufacturer (systematic error or relatively fixed between repeated measures), the most likely sources of variation in the data collected are associated to the examiner and to changes in the natural scapular position and orientation (random errors that need to be minimized and estimated whenever possible). Although the systematic error involving the examiner cannot be completely ruled out, in this study, the person responsible for the creation of the local coordinate system of segments was submitted to a period of six months of training, repeating the necessary steps. Although not investigated in this study, the learning curve effect was observed during the training period, previously to procedures of this study, pointing to importance of this step for consistency of results.

However, a source of systematic error is this study cannot be controlled or minimized are muscles overloads, which are derived from physical activity or exercise, physical or psychological effects on posture to which participants may have been exposed, especially in inter-day assessments⁽ ³ ^, ²⁴ ⁾.

Regarding the scapular position in relation to the thorax during maintenance of ortostatia, a variety of results can be found in literature⁽ ³ ^, ⁴ ^, ⁹ ⁾. The present study found that scapula of dominant limb is at approximately 4° of upward rotation, 31° of medial rotation and 10° of anterior tilt.

Ludewig et al.⁽²⁵⁾ found similar results with values of 5° of upward rotation, 41° of medial rotation and 13° of anterior tilt in a sample of healthy subjects and using electromagnetic sensors attached to pins transcortically inserted into the bones of the shoulder complex ⁽²⁵⁾. Except for the medial rotation, the values reported by Ludewig et al.⁽²⁵⁾ are similar to those found in this study, in which the effect of the movement of sensors on the skin of volunteers on the values found was considered minimum.

Oyama et al.⁽⁴⁾ compared the resting scapular position of healthy shot put athletes in relation to the dominant and non-dominant limb and found that the dominant limb had greater upward rotation, greater internal rotation and greater anterior tilt⁽⁴⁾. In our sample of individuals not engaged in physical or sports activities with upper limbs, higher internal rotation and anterior tilt values in the dominant limb and higher upward rotation were found in the non-dominant limb.

On the cost-benefit ratio considering records of static posture, previous studies have used photogrammetry, which is relatively cheaper than electromagnetic systems, and found conflicting inter-day reliability values for scapular symmetry measures⁽ ²⁶ ^, 27 ⁾, while data of the present study revealed that repeated measures in distinct procedures for obtaining data via electromagnetic systems are more reliable and, given the estimate of absolute error of measurements, allow researchers to track natural changes or those resulting from interventions.

Finally, considering the current relevance given the scapula in the context of evaluation and treatment of shoulder disorders (28), the possible influences of pain on muscle activity and amount of use of the upper limb during functional activities, further studies are needed to establish the reliability the variables tested in sports activities and in patients who have pain and reduction in the use of the stabilizing muscles of the scapula or with scapular dyskinesis diagnosis.

CONCLUSION

Results presented in this study indicate that the linear and angular measurements for determining the resting scapular position of asymptomatic and sedentary population are reliable, which were achieved through an electromagnetic system for three-dimensional movement record. Taking into account the need to evaluate the influence of scapular dyskinesis and the amount of use of the upper limbs in functional and sports activities, further reliability studies should be carried out using the same system to assess resting scapular position in samples of participants with symptomatic dysfunction of the shoulder complex and in participants in professional or recreational sports activities.

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Received: October 17, 2013; Accepted: April 23, 2014

Progressive resistance training in chronic musculoskeletal disorders

Progressive resistance training in chronic musculoskeletal disorders

Renata Trajano Jorge^I; Marcelo Cardoso de Souza^II; Anamaria Jones^III; Império Lombardi Júnior^IV; Fábio Jennings^V; Jamil Natour^VI

^IPhysical Therapist, PhD Student in Rheumatology, UNIFESP
^IIPhysical Therapist, MD Student in Rheumatology at UNIFESP, Specialist in Exercise Physiology and ResistanceTraining in Health, Disease, and Aging - IBEP-USP
^IIIPhysical Therapist, PhD in Rehabilitation, UNIFESP
^IVPhysical Therapist, Professor of the Health Sciences Department, UNIFESP
^VPhysician, PhD Student in Rheumatology, UNIFESP
^VIProfessor of Rheumatology, UNIFESP

ABSTRACT

INTRODUCTION: Progressive resistance training has been suggested as a therapeutic modality that attempts to promote the standardization of the prescription of physical exercises in physical therapy, besides optimizing the results of the treatment.
OBJECTIVE: To review studies that used progressive resistance training in chronic musculoskeletal diseases and to demonstrate the importance of including this type of training in the rehabilitation of those diseases.
SOURCE OF THE DATA: Pubmed, Medline, and Lilacs databases were reviewed without restrictions of date and/or language.
REVIEW: Due to the countless benefits attributed to this treatment modality, the importance of exercises in physical therapy has been well documented. Despite the proven efficacy, high-intensity exercises are not routinely prescribed, and this prescription is usually not standardized, which does not allow a consensus on the type of strengthening used, as well as load calculation and progression. Progressive resistance training implies the gradual increase in load during the training period. The number of repetitions that each individual can complete depends on the calculation of the maximal repetition.
CONCLUSION: Based on the findings of this review, the use of progressive resistance training to complement traditional exercises used in rehabilitation of chronic musculoskeletal diseases is recommended in order to standardize treatment protocols, with adequate control of individual load, and to optimize training results. However, it should be emphasized that further studies are necessary for more reliable conclusions.

Keywords: physical therapy, exercises, musculoskeletal diseases.

INTRODUCTION

The importance of exercises in physical therapy, especially in patients with chronic diseases, is based on reliable evidence of the countless benefits of this therapeutic modality, mainly promoting quality of life and improving functional capacity. Exercises have become even more important, since many doubts on the use and efficacy of physical means, both due to the insufficient number of studies and their poor methodological quality, remain.^1-5

Despite their proven efficacy, the ideal regimen is still debatable. Several studies describing the importance of different types of exercises in chronic diseases can be found. Conventional and high-impact, such as aerobic and resistance exercises are among those mentioned more often.^1,6,7

Regarding high-intensity exercises, especially in patients with rheumatologic diseases, the opinions of patients and experts are divergent. A recent study evaluated the opinion of patients, rheumatologists, and physical therapists regarding the expectations of this group on the use of conventional therapeutic exercises versus high-intensity exercises in patients with rheumatoid arthritis. All three groups were more favorable to the use of conventional exercises, especially, and at a higher degree, the group of physical therapists.⁸

This demonstrates the difficulty of professionals in prescribing and using high-intensity exercises in patients with chronic diseases. On the other hand, some studies have demonstrated the benefits and importance of resistance training in the treatment of patients with chronic diseases, showing good results especially regarding pain, function, and quality of life.^9,10

MATERIAL AND METHODS

The search included Pubmed, Medline, and Lilacs databases, with no restrictions of dates and languages, using the following keywords: physical therapy, exercises, resistance exercise, progressive resistance exercise, resistance training, progressive resistance training, and musculoskeletal diseases. One hundred and eighty-six studies were found, but only 31 were included in this study. To be included, studies should have some type of exercise with external resistance, either manual, with the use of machines, ankle weights, or weights, among others.

Resistance Training

Resistance training is defined as an activity that develops and maintains strength, resistance, and muscle mass, and it has been practiced by a wide variety of individuals with and without chronic diseases, since it is associated with favorable changes in cardiovascular function, metabolism, coronary artery disease risk factors, and psycho-social well-being. Besides, those exercises stimulate muscle hypertrophy and coordination, showing functional improvement of activities of daily living.^11-13

The inclusion of this type of exercise in musculoskeletal rehabilitation had a great impulse and scientific recognition from the II World War on, when the importance of resistance training in improving the muscular strength of military personnel was demonstrated.¹²

Currently, studies have been emphasizing the potential benefits of resistance training in physical therapy, especially in the treatment of different rheumatologic disorders, since strength deficit is a common finding in most of those diseases, contributing for the incapacity to perform common activities.^9,14

Suetta et al. (2004) demonstrated that, contrary to conventional physical therapy, resistance training increases muscle mass, maximal muscular strength, and neuronal stimuli in elderly individual with limb disuse after hip arthroplasty.¹⁵

Andersen et al. (2006) investigated muscular activation in conventional therapeutic exercises versus resistance exercises and concluded that neuromuscular activation in conventional exercises is below the 40-60% necessary to stimulate gain in muscle strength.¹⁶

Taylor et al. (2005) investigated systematic reviews on the use of resistance training in different specialties, with emphasis on cardiopulmonary, neuromuscular, gerontological, and musculoskeletal disorders. Regarding the last ones, the following studies were found.¹⁴

1. Two reviews of chronic back pain, with 18 studies, demonstrating an improvement of trunk extensor and flexor strength with reduction in pain and improved function;

2. One review of cervical neck pain, with four studies, demonstrating improvement in strength, amplitude of movements, function, and pain;

3. One review of hip and knee osteoarthritis, with two studies, demonstrating a reduction in pain;

4. One review of femur and ankle fracture, with three studies, demonstrating improvement in strength and function.

In reviews of lumbalgia and cervicalgia, patients were instructed to perform one to four exercises using different resistances, which included machines, body weight, and exercises without any load. Participants completed one to three series of eight to 12 repetitions based on eight to 12 maximal repetitions (MR) two to three times a week for 12 weeks. According to the authors, the studies were difficult to evaluate because some of the parameters did not follow principles of progressive resistance training.¹⁴

Analyzing the studies on hip and knee osteoarthritis, the authors considered that they followed principles of progressive resistance training, applying two series of 12 repetitions, based on 12 MR, three times a week for 18 months, and progressive resistance after three consecutive days of training if the participant was able to finish the training easily. It was not clear, in those studies, how resistance was calculated and evaluated.¹⁴

On the review of fractures, only three studies, with a small number of participants, could be evaluated. They performed two to three series of eight to 12 repetitions with an intensity of 50 to 90% of MR, two to three times a week for 12 weeks. The authors did not describe if and how load progression was achieved.¹⁴

A systematic review of the Cochrane database evaluated the effects of progressive resistance exercises on physical disability and function in the elderly. The review considered the methodological quality of the studies poor, but reported that training promoted a positive effect in some functional limitations. Neither the side effects of this intervention, nor the presence of periodic progression of the load, and how it was done, were reported.¹⁷

Although most of the studies reported positive results for some parameters, the heterogeneous methodologies do not allow a consensus on the interventions used, load calculation, if it was progressive, and how this progression was done.^18-24

Progressive Resistance Training

In view of what has been exposed, standardization and individualization of protocols are important to optimize treatment results and to allow the reproduction of those protocols in future studies.

The expression progressive resistance training it is not used often and studies mention the word strength more frequently, but it is very criticized because it is vague and it does not define the type of strengthening being done.^14,17

Discussions, and the consensus among the studies, hover around the need of progression of resistance training to achieve the desired results, especially regarding neuromuscular activation, increased strength, and muscular hypertrophy.^14,17,25,26

Progressive resistance training means a gradual increase in load during the training period and should always been monitored by a trained professional,^6,17,25The number of repetitions that each individual can tolerate depends on the external resistance, i.e., the load imposed during the exercise, which is called MR in the studies published: for example, 1MR indicates the maximal load tolerated with one repetition.^7,22

The American College of Sports Medicine recommends that beginners or those with intermediate training use 60 to 70% of 1MR for two or three series of 8-12 repetitions, and that MR should be recalculated periodically. Any level above those mentioned can be considered a high load.^22,25

The resting period recommended for beginners or intermediate individuals is 1-2 minutes, respectively. Initially, non-trained individuals or beginners should perform the exercises at a slow or intermediate speed 2-3 times a week.^22,25

It is also recommended that eccentric and concentric exercises should be included in the training program, and both mono- and polyarticular exercises have been proven to be effective in increasing muscular strength.^22,25

Jan et al. (2008) investigated and compared the clinical effects of physical exercises with high (60% of 1MR) and low (10% of 1MR) resistance in patients with knee osteoarthritis.

The load was reevaluated every two weeks. The authors did not observe statistically different results regarding improvement in strength and in function.³

Beneka et al. (2005) investigated the gain in muscular strength in the elderly with exercises with high (90%), medium (70%), and low (50%) resistance. The load was evaluated every two weeks. The authors concluded that the group who performed high-resistance exercises had greater increase in strength.²¹

Alexanderson et al. (2007) evaluated the benefits and safety of high-intensity muscular training in patients with chronic myopathies. Patients trained three days a week for seven weeks with upper and lower limb exercises. They started the exercises with 50% of 10 MR and this load was increased progressively every two weeks. At the end of the training program, the authors observed gains in function without changes in the levels of muscular inflammation.²⁷

Rall et al. (1996) investigated the benefits of progressive resistance training in patients with non-active rheumatoid arthritis. Patients were instructed to perform the exercises for upper and lower limbs on exercise machines with three series of eight repetitions twice a week for 12 weeks, with a load of 80% of 1MR. Maximal repetitions were evaluated every two weeks. The authors concluded that this type of training is viable and safe for patients whose disease is under control, and they observed improvements in strength, pain, and fatigue, without exacerbating disease activity.²⁸

Studies following the principles of progressive resistance training regarding the calculation of the initial load and its progression in patients with ankylosing spondylitis and other rheumatic diseases, other than those mentioned here, were found.

In Brazil, very few studies on progressive resistance training in musculoskeletal rehabilitation were found. Among them, we can mention the study of Lombardi Júnior et al. (2008) who used progressive resistance training in a randomized controlled study, and evaluated pain, function, muscular strength, and quality of life of patients with impact syndrome. Patients performed two series of eight repetitions, the first series with 50% of 6MR and the 2^ndseries with 70% of 6MR, twice a week for eight weeks. Maximal resistance was reevaluated every two weeks. At the end of the study, pain, function, and quality of life of patients improved when compared to the control group.²⁹

Safety in progressive resistance training

Regarding the safety of this type of training, the studies found did not report any intercurrence that could compromise the use of this type of training by sick people, but individuals with severe comorbidities were not included in the studies and, therefore, we cannot extrapolate those results for the general population. The main contraindications of progressive resistance training are the same for any other physical activity. Among them, we should mention: unstable coronary insufficiency, unstable heart failure, uncontrolled arrhythmia, recent acute myocardial infarction, blood pressure above 180x100 mmHg, severe hypertrophic cardiomyopathy, severe chronic obstructive pulmonary disease, acute thrombophlebitis, severe metabolic changes, acute infections, acute arthritis, and complicated pregnancy.^{10,13,14,26,30,31}

FINAL CONSIDERATIONS

Based on those findings, we should recognize the importance of progressive resistance training and recommend its use as complementary to traditional therapeutic physical exercises used in musculoskeletal rehabilitation to standardize and individualize the protocols used, controlling and adjusting the load, and try to induce enough levels of neuromuscular activation to stimulate hypertrophy and gain in muscular strength.

Despite the controversies among the studies on what is considered low, medium, and high loads, we believe that we can consider loads up to 30% of MR low, from 30 to 60% medium, and above 60% high. However, further studies should be stimulated to obtain stronger conclusions.

REFERENCES

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3. Jan MH, Lin JJ, Liau JJ, Lin YF, Lin DH. High and low resistance training for patients with knee osteaoarthritis: a randomized controlled trial. Phys Ther 2008; 88(4):427-36. [ Links ]

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7. Fish DE, Krabak BJ, Johnson-Greene D, DeLateur BJ. Optimal resistance training: comparison of DeLorme with Oxford techniques. Am J Phys Med Rehabil. 2003; 82(12):903-9. [ Links ]

8. Munneke M, Jong Z, Zwinderman AH et al. High intensity exercise or conventional exercise for patients with rheumatoid arthritis? Outcome expectations of patients, rheumatologists, and physiotherapists. Ann Rheum Dis 2004; 63:804-8. [ Links ]

9. Winnett RA, Carpinelli RN. Potential health-related benefits of resistance training. Prev Med 2001; 33:503-13. [ Links ]

10. Enoka RM. Strength training for exercise performance and Rehabilitation. Scand J Med Sci Sports 2007; 17(1). [ Links ]

11. Graves JE, Franklin BA. Treinamento Resistido na Saúde e Reabilitação. Rio de Janeiro: Revinter, 2006. [ Links ]

12. De Lorme TL. Restoration of muscle power by heavy resistance exercises. J Bone Joint Surg 1945; 27:645-67. [ Links ]

13. Kelley GA, Kelley KS. Progressive resistance exercise and resting blood pressure: a meta-analysis of randomized controlled trials. Hypertension 2000; 35:838-43. [ Links ]

14. Taylor NF, Dodd KJ, Damiano DL. Progressive resistance exercise in physical therapy: a summary of systematic reviews. Phys Ther 2005; 85:1208-23. [ Links ]

15. Suetta C, Aagaard P, Rosted A. Training-induced changes in muscle CSA, muscle strength, EMG and rate of force development in elderly subjects after long-term unilateral disuse. J Appl Physiol 2004; 97:1954-61. [ Links ]

16. Andersen LL, Magnusson SP, Nielsen M, Hallem J, Poulsen K, Aagaard P. Neuromuscular activation in conventional therapeutic exercises and heavy resistance exercises: implications for rehabilitation. Phys Ther 2006; 86(5):683-97. [ Links ]

17. Latham N, Anderson C, Bennett D, Stretton C. Progressive resistance strength training for physical disability in older people. Cochrane Database Syst Rev 2003; 2:CD002759. [ Links ]

18. Mikesky AE, Mazzuca SA, Brandt KD, Perkins, SM, Damush T, Lane KA. Effects of Strength Training on the Incidence and Progression of Knee Osteoarthritis. Arthritis Rheum 2006; 55(5):690-99. [ Links ]

19. Folland JP, Williams AG. The adaptations to strength training: morphological and neurological contributions to increased strength. Sports Med 2007; 37(2):145-68. [ Links ]

20. Pisters MF, Veenhof C, Nico LU et al. Long-Term Effectiveness of Exercise Therapy in Patients With Osteoarthritis of the Hip or Knee: A Systematic Review. Arthritis Rheum 2007; 57(7):1245-53. [ Links ]

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24. Kryger AI & Andersen JL. Resistance training in the oldest old: consequences for muscle, strength, fiber types, fiber size and MHC isoforms. Scand J Med Sci Sports 2007; 17:422-30. [ Links ]

25. Kraemer WJ, Adams K, Cafarelli E et al. Progression models in resistance training for healthy adults. Med Sci Sports Exerc 2002; 34(2):364-75. [ Links ]

26. Bennell KL, Hunt MA, Wrigley TV, Hunter DJ,Hinman RS. The effects of hip muscle strengthening on knee load, pain, and function in people with knee osteoarthritis: a protocol for a randomized, single-blind controlled trial. BMC Musculoskeletal Disorders 2007, 8(121):1-9. [ Links ]

27. Alexanderson H, Dastmalchi M, Rnssonon-Liljedahl ME, Opava CH, Lundberg IE. Benefits of Intensive Resistance Training in Patients with Chronic Polymyositis or Dermatomyositis. Arthritis Rheum 2007; 57( 5):768-77. [ Links ]

28. Rall LC, Meydani SN, Kehayias JJ, Dawson-Hughes B, Roubenoff R. The effect of progressive resistance training in rheumatoid arthritis. Increased strength without changes in energy balance or body composition. Arthritis Rheum 1996; 39(3):415-26. [ Links ]

29. Lombardi I Jr, Magri AG, Fleury AM, Da Silva AC, Natour J. Progressive resistance training in patients with shoulder impingement syndrome: A randomized controlled trial. Arthritis Rheum 2008; 59(5):615-22. [ Links ]

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31. Baker KR, Nelson ME, Felson DT et al. The efficacy of home based progressive strength training in older adults with knee osteoarthritis: a randomized controlled trial. J Rheumatol 2001; 28(7):1655-65. [ Links ]

Treinamento resistido progressivo nas doenças musculoesqueléticas crônicas

Treinamento resistido progressivo nas doenças musculoesqueléticas crônicas

Renata Trajano Jorge^I; Marcelo Cardoso de Souza^II; Anamaria Jones^III; Império Lombardi Júnior^IV; Fábio Jennings^V; Jamil Natour^VI

^IFisioterapeuta, Doutoranda da disciplina de Reumatologia, UNIFESP
^IIFisioterapeuta, Mestrando da disciplina de Reumatologia da UNIFESP, Especialista em Fisiologia do Exercício e Treinamento Resistido na Saúde, na Doença e no Envelhecimento - IBEP- USP
^IIIFisioterapeuta, Doutora em Reabilitação, UNIFESP
^IVFisioterapeuta, Professor Adjunto do departamento de Ciências da Saúde, UNIFESP
^VMédico, Doutorando da disciplina de Reumatologia, UNIFESP
^VIProfessor da disciplina de Reumatologia, UNIFESP

RESUMO

INTRODUÇÃO: O treinamento resistido progressivo tem sido sugerido como uma modalidade terapêutica que tenta promover uma padronização da prescrição de exercícios em fisioterapia, além de otimizar os resultados da terapia.
OBJETIVO: Revisar os estudos que utilizaram o treinamento resistido progressivo em doenças musculoesqueléticas crônicas e demonstrar a importância da inclusão deste tipo de treinamento na reabilitação destas doenças.
FONTE DE DADOS: A pesquisa foi realizada através dos bancos de dados Pubmed, Medline e Lilacs sem restrições a datas e/ou idiomas.
REVISÃO: Já se encontra bem fundamentada a importância da aplicação de exercícios terapêuticos em fisioterapia devido aos inúmeros benefícios atribuídos a esta modalidade terapêutica. Apesar de comprovadamente eficazes, os exercícios de alta intensidade ainda não são prescritos rotineiramente e esta prescrição geralmente não é feita de maneira padronizada, não nos permitindo chegar a um consenso quanto ao tipo de fortalecimento utilizado, o cálculo da carga e a sua progressão. O treinamento resistido progressivo é realizado através do aumento gradual de carga durante o período de treinamento. O número de repetições que cada indivíduo pode completar depende do cálculo da repetição máxima.
CONCLUSÃO: Baseando-se nos achados desta revisão, recomenda-se o uso de exercícios resistidos progressivos como complemento dos exercícios tradicionais utilizados na reabilitação de doenças musculoesqueléticas crônicas para que seja possível padronizar os protocolos de atendimento, controlando e adequando individualmente a carga, e otimizar os resultados do treinamento. No entanto, vale ressaltar que novos estudos são necessários para que se chegue a conclusões mais fidedignas.

Palavras-chave: fisioterapia, exercícios, doenças musculoesqueléticas.

INTRODUÇÃO

Já se encontra bem fundamentada a importância da aplicação de exercícios terapêuticos em fisioterapia, em especial em doentes crônicos, devido aos inúmeros benefícios atribuídos a esta modalidade terapêutica, principalmente no que diz respeito à promoção da qualidade de vida e melhora da capacidade funcional. Os exercícios tornam-se ainda mais importantes, já que muitas dúvidas permanecem quanto à utilização e à eficácia dos meios físicos, tanto pelo número insuficiente de estudos quanto pela sua baixa qualidade metodológica.^1-5

Apesar de comprovadamente eficazes, muito ainda se discute com relação ao esquema ideal a ser adotado. Diversos estudos podem ser encontrados descrevendo a importância dos mais variados tipos de exercícios utilizados em doenças crônicas. Entre os exercícios citados nestes estudos estão os exercícios terapêuticos convencionais e até mesmo, exercícios de alta intensidade, como os aeróbicos e os resistidos.^1,6-7

Quando se trata de exercício de alta intensidade, especialmente em pacientes reumáticos, as opiniões dos pacientes e dos próprios especialistas ainda se mostram bastante divergentes. Um estudo recente avaliou a opinião de pacientes, reumatologistas e fisioterapeutas com relação à expectativa destes grupos sobre a aplicação de exercícios terapêuticos convencionais versus exercícios de alta intensidade em pacientes com artrite reumatoide. Os três grupos se mostraram mais favoráveis à aplicação de exercícios convencionais, especialmente e em maior grau, o grupo composto por fisioterapeutas.⁸

Dado este que denota, ainda, certa dificuldade dos próprios profissionais em prescrever e utilizar os exercícios de alta intensidade em pacientes portadores de doenças crônicas.

Por outro lado, alguns trabalhos já vêm se preocupando em demonstrar os benefícios e a importância do exercício resistido no tratamento de doentes crônicos com apresentação de bons resultados, principalmente, no que se refere à dor, função e qualidade de vida.^9,10

MATERIAL E MÉTODOS

A pesquisa foi realizada através dos bancos de dados Pubmed, Medline e Lilacs, sem restrições a datas ou idiomas, através das seguintes palavra-chave: fisioterapia, exercício, exercício resistido, exercício resistido progressivo, treinamento resistido, treinamento resistido progressivo, doenças músculo esqueléticas e suas respectivas traduções para o Inglês. Foram encontrados 186 estudos e incluídos apenas 31. Os estudos incluídos precisavam ter em sua descrição alguma forma de exercício com resistência externa , fosse ela manual, com o uso de aparelhos, caneleiras, halteres, entre outras.

Treinamento Resistido

O treinamento com exercícios resistidos é definido como uma atividade que desenvolve e mantém a força, a resistência e a massa muscular e tem sido praticado por uma grande variedade de indivíduos com e sem doenças crônicas, porque está associado a mudanças favoráveis na função cardiovascular, metabolismo, fatores de risco coronários e bem-estar psicossocial. Além disso, estes exercícios estimulam a hipertrofia e a coordenação, trazendo assim melhora funcional das atividades de vida diária.^11-13

A inclusão deste tipo de exercício na reabilitação musculoesquelética teve grande impulso e reconhecimento científico a partir da segunda guerra mundial quando se demonstrou a importância dos exercícios resistidos para melhora da força muscular dos militares.¹²

Nos dias atuais, estudos têm enfatizado os benefícios potenciais da aplicação dos exercícios resistidos em fisioterapia e, especialmente, no tratamento de diversas doenças reumatológicas, já que o déficit de força é um achado comum na maioria destas doenças e que contribui fortemente para inabilidade em realizar atividades corriqueiras.^9,14

Suetta et al. (2004) atestaram que o treinamento resistido, ao contrário da fisioterapia convencional, aumenta a massa muscular, a força muscular máxima e os estímulos neurais em indivíduos idosos com desuso do membro pós artroplastia de quadril.¹⁵

Andersen et al. (2006) estudaram a ativação neuromuscular em exercícios terapêuticos convencionais versusexercícios resistidos e chegaram à conclusão de que os exercícios convencionais produzem ativação neuromuscular abaixo dos 40-60% necessários para estimular o ganho de força muscular.¹⁶

Taylor et al. (2005) fizeram um levantamento das revisões sistemáticas que abordavam o exercício resistido em diferentes especialidades, com ênfase em doenças cardiopulmonares, neuromusculares, gerontológicas e musculoesqueléticas. No que diz respeito a estas últimas, foram encontrados os seguintes trabalhos:¹⁴

• Duas revisões de lombalgia crônica, com 18 estudos, onde se verificou melhora da força extensora e flexora de tronco com redução da dor e melhora da função;

• Uma revisão de cervicalgia, com quatro trabalhos, que verificou melhora de força, amplitude de movimento, função e dor;

• Uma revisão de osteoartrite de quadril e joelho com dois estudos que redução da dor;

• Uma revisão de fratura de fêmur e tornozelo, com três estudos, que verificou melhora da força e da função.

Nos estudos pertencentes às revisões de lombalgia e cervicalgia, os pacientes eram orientados a realizar de um a quatro exercícios, utilizando resistências variadas que incluíam pesos de máquinas, peso corporal e também, exercícios sem carga. Os participantes completavam de uma a três séries de 8 a 12 repetições baseadas em 8 a 12 repetições máximas (RM), 2 a 3 vezes por semana, durante 12 semanas. Os autores desta revisão julgaram os estudos como de difícil avaliação, pois alguns parâmetros utilizados não condiziam com os princípios do treinamento resistido progressivo.¹⁴

Na análise dos estudos referentes à osteoartrite de quadril e joelhos, os autores da revisão julgaram os estudos como condizentes com o que dita os princípios do treinamento resistido progressivo, aplicando exercícios com duas séries de 12 repetições baseados em 12 RM, três vezes por semana, durante 18 meses e resistência progressiva a partir de três dias consecutivos de treino, caso o participante conseguisse completar com facilidade seu treino. Os estudos não deixaram claro como esta resistência foi calculada e reavaliada.¹⁴

Com relação à revisão de fraturas, somente três estudos puderam ser avaliados e com um pequeno número de participantes. Estes realizaram exercícios com duas a três séries de oito a 12 repetições com uma intensidade de 50 a 90% de uma RM por duas a três vezes por semana durante 12 semanas. Os autores não descreveram se houve e como foi feita a progressão da carga.¹⁴

Uma revisão sistemática da Cochrane avaliou o efeito dos exercícios resistidos progressivos em medidas de incapacidade física e função em idosos. A revisão julgou a qualidade metodológica dos estudos ruim, mas atestou que o treinamento utilizado promoveu um efeito positivo em algumas limitações funcionais. Os efeitos colaterais desta intervenção não foram relatados e não houve descrição da existência de progressão periódica da carga e como esta foi realizada.¹⁷

Apesar da maioria dos estudos ter encontrado resultados positivos em algumas medidas de avaliação, sua metodologia heterogênea ainda não nos permite chegar a um consenso com relação às intervenções utilizadas, o cálculo da carga, se houve progressão e como foi realizada esta progressão.^18-24

Treinamento Resistido Progressivo

Diante do exposto acima, percebe-se a importância da padronização e individualização dos protocolos de atendimento para que os resultados do tratamento sejam otimizados e, mais que isso, para que esses protocolos possam ser reproduzidos em estudos futuros.

O termo treinamento resistido progressivo ainda é pouco utilizado e a palavra fortalecimento é a mais referida nos trabalhos, porém recebe muitas críticas por ser um termo vago que não define o tipo de fortalecimento que está sendo utilizado.^14,17

O tema mais discutido e que é consenso entre os trabalhos é que o programa de treinamento resistido necessita ser progressivo para que alcance os resultados almejados, principalmente no que diz respeito à ativação neuromuscular, ao ganho de força e hipertrofia muscular.^{14,17, 25,26}

O treinamento resistido progressivo é realizado através do aumento gradual de carga durante o período de treinamento e deve ser sempre monitorado por um profissional capacitado.^6,17,25O número de repetições que cada indivíduo pode tolerar depende da resistência externa, ou seja, da carga imposta durante a execução daquele exercício, que é referida nos trabalhos como RM, por exemplo, uma RM indica o máximo de carga que é tolerada com uma repetição.^7,22

O Colégio Americano de Medicina Esportiva recomenda que indivíduos iniciantes ou com treinamento intermediário utilizem carga correspondente a 60 ou 70% de 1 RM para duas ou três séries de oito a 12 repetições e que a RM seja recalculada periodicamente. Qualquer valor superior aos supracitados já pode ser considerado uma carga alta.^22,25

O período de repouso recomendado para indivíduos iniciantes e intermediários é de respectivamente de um e dois minutos. Para indivíduos não treinados ou iniciantes são recomendados que os exercícios sejam realizados com velocidades baixas ou intermediárias, inicialmente e com uma frequência de 2 ou 3 vezes por semana.^22,25

Também é preconizado que o exercício excêntrico e o concêntrico devem ser incluídos nos programas de treinamento e que tanto exercícios monoarticulares quanto exercícios poliarticulares tem se mostrado efetivos no ganho de força muscular.^22,25

Jan et al. (2008) investigaram e compararam os efeitos clínicos de exercícios com alta resistência (60% de 1 RM) e de exercícios com baixa resistência (10% de 1 RM) em pacientes com osteoartrite de joelhos. A carga era reavaliada a cada duas semanas. Os autores não encontraram resultados diferentes estatisticamente em relação a ganhos de força e função.³

Beneka et al. (2005) investigaram o ganho de força muscular em idosos através do treinamento com exercícios de alta (90%), média (70%) e baixa (50%) resistência. A carga era reavaliada a cada duas semanas. Os autores concluíram que o maior ganho de força ocorreu no grupo que recebeu treinamento com exercícios de alta resistência.²¹

Alexanderson et al. (2007) avaliaram os benefícios e a segurança do treinamento muscular de alta intensidade em pacientes com miopatias crônicas. Os pacientes foram submetidos a três dias de treinamento por semana durante sete semanas com exercícios tanto para membros superiores quanto inferiores. Os pacientes iniciavam os exercícios com 50% de 10 RM e essa carga era progressivamente aumentada a cada duas semanas. Ao fim do treinamento, os autores constataram ganhos na função, sem alteração dos níveis de inflamação muscular.²⁷

Rall et al. (1996) estudaram os benefícios do treinamento resistido progressivo em pacientes com artrite reumatoide fora de atividade. Os pacientes foram instruídos a realizar exercícios em máquinas para membros superiores e membros inferiores com três séries de oito repetições, duas vezes por semana, durante 12 semanas, com carga de 80% de uma RM. A cada duas semanas a RM era reavaliada. Os autores concluíram que esse tipo de treino é viável e seguro para pacientes com doença controlada e mostrou ganhos na força, dor e fadiga, sem exacerbação da atividade da doença.²⁸

Nenhum estudo que segue os princípios do treinamento resistido progressivo, no que diz respeito ao cálculo inicial da carga e sua progressão, foi encontrado em pacientes com espondilite anquilosante e outras doenças reumatológicas não citadas nesta revisão.

No Brasil, até o momento, poucos estudos foram encontrados a respeito do treinamento resistido progressivo em reabilitação musculoesquelética. Entre eles, podemos citar o estudo desenvolvido por Lombardi Júnior et al.(2008) que utilizou o treinamento resistido progressivo em trabalho randomizado e controlado avaliando dor, função, força muscular e qualidade de vida em pacientes com síndrome do impacto. Os pacientes foram submetidos a duas séries de oito repetições, sendo a 1ª série com 50% de seis RM e a 2ª série com 70% de seis RM, duas vezes por semana, por um período de oito semanas. As RM eram reavaliadas a cada duas semanas. Ao final do estudo, houve melhora da dor, função e qualidade de vida destes pacientes quando comparados ao grupo controle.²⁹

Segurança no treinamento resistido progressivo

No que diz respeito à segurança desse tipo de treinamento, até o momento, os estudos encontrados não relataram qualquer intercorrência que pudesse comprometer a inclusão desse tipo de treino entre pessoas doentes, mas deve-se ressaltar que indivíduos com comorbidades graves não foram incluídos nos trabalhos, o que não nos permite estender os resultados para a população em geral. As principais contraindicações do treinamento resistido progressivo são as mesmas contraindicações de qualquer outra atividade física. Dentre as principais podemos citar: insuficiência coronariana instável, insuficiência cardíaca instável, arritmia não controlada, infarto agudo do miocárdio recente, pressão arterial acima de 180/110 mmHg, miocardiopatia hipertrófica grave, doença pulmonar obstrutiva crônica grave, tromboflebite aguda, alterações metabólicas graves, infecções agudas, artrite aguda e gravidez complicada. ^{10,13-14,26,30-31}

CONSIDERAÇÕES FINAIS

Baseados nesses achados, devemos reconhecer a importância do treinamento resistido progressivo e recomendar seu uso como complemento dos exercícios terapêuticos tradicionais utilizados em reabilitação musculoesquelética para que se possa padronizar e individualizar os protocolos de atendimento, controlando e adequando a carga e, além disso, tentar induzir níveis suficientes de ativação neuromuscular a fim de estimular a hipertrofia e o ganho de força muscular.

Apesar de ainda haver muita controvérsia entre os estudos sobre o que considerar carga baixa, média e alta, acreditamos que podem ser consideradas cargas baixas as cargas com até 30% da RM, de 30% a 60% cargas médias e a partir desse valor, cargas altas.

No entanto, novas pesquisas devem ser incentivadas para que se consiga chegar a conclusões mais contundentes.

REFERÊNCIAS