Mat Pilates improves lower and upper body strength and flexibility in breast cancer survivors undergoing hormone therapy: a randomized controlled trial (HAPiMat study)

Abstract Purpose To evaluate the effects of 24 weeks of Mat Pilates in breast cancer survivors (BCS) undergoing hormone therapy on lower and upper body muscle strength parameters and flexibility. Materials and methods Forty-three BCS (≥40 years) with confirmed breast cancer stage 0–III undergoing hormone therapy were included. Participants were randomized into Mat Pilates (three times/week, 60 min session) or control group (relaxation activities every two weeks). The difficulty and number of exercise repetitions were increased over the weeks. Assessments were performed at three times points (baseline, 12 weeks, and 24 weeks). The generalized estimating equations (GEE) model was used to compare each outcome measure during the analysis of intention to treat (ITT) and “Per protocol analysis” (PPA). Results The Pilates group presented significantly increased (p < 0.05) isometric flexor–extensor PT, and concentric and eccentric flexor PT and mechanical work (MW) after the intervention. Most of the upper body strength parameters, time to achieve maximal force (TFmax), maximal force (F max), and rapid force index (RFI) and right-left upper and lower body flexibility (p < 0.05) also improved. Conclusions From our findings, we conclude that 24 and 12-weeks of Mat Pilates induced strength and flexibility gains for lower and upper body, respectively. Implications for rehabilitation Mat Pilates can be adapted to the fitness level of breast cancer survivors, with a great variety of exercises that can be performed using a mat only or a few pieces of equipment. Patients can practice at home to gain different health benefits (i.e., increasing strength, flexibility, and functional capacity level), which could positively impact on quality of life. Mat Pilates performed three times per week with systematized increments in exercise level, load, and volume throughout the intervention was effective to improve hip extensor–flexor muscles peak torque and mechanical work at different muscle contractions, as well as upper and lower body flexibility. Mat Pilates was also able to improve right-left shoulder abductor and trunk extensor muscles strength parameters after 12 weeks of intervention, as well as both surgery and non-surgery sides of the upper body.


Introduction
The average life expectancy has risen among breast cancer survivors (BCS) due to early detection and treatment advances [1]. Nonetheless, long-term side effects such as decreased shoulder range of motion and muscle strength on the surgical side are observed [2]. Different from radiotherapy and surgery, which affect specific muscles of the upper body (i.e., shoulder muscles), chemotherapy is a systemic therapy that can also lead to strength loss in muscle groups not affected by the cancer per se [3].
When considering hormone therapy, which involves administration of aromatase inhibitors (AIs) or selective modulators of estrogen receptors (SMREs), different side effects are reported [4]. Among the musculoskeletal side effects of AIs are joint stiffness and pain [5], as well as loss of lean mass and muscle strength. In contrast, SMREs are associated with fatigue, and lower and upper body numbness [1], which might be related to muscle strength loss [6]. Morales et al. [7] showed a large decrease in handgrip strength after six months of hormone therapy that appears to be related to tendon and joint changes, mainly in AIs compared to tamoxifen (TMX), which is an SMRE. In this context, a recent study [8] showed that BCS undergoing hormone therapy presented lower force production in knee flexor-extensors, trunk extensors, and right and left shoulder abductors compared with women without a cancer history. The decrease in range of motion due to tendon joint stiffness and the muscle strength loss can negatively impact functional capacity, and, consequently, quality of life in BCS [9].
Conversely, physical exercise can improve the efficacy of breast cancer treatments and mitigate the side effects [10], with enhancements in physical fitness [11], muscle strength [12], and upper body mobility [13]. Pilates has been widely sought in recent decades to enhance physical fitness and rehabilitation [14]. Pilates method exercises can be practiced on different equipment or on the floor (Mat Pilates), with or without accessories or even just using body weight [15,16] based on core muscle stabilization and quality of the movements [17]. The Pilates method works on muscle flexibility and joint mobility [18,19], muscular strength [20], and balance [21] combined with breathing and concentration techniques [16,17]. Considering the side effects of hormone therapy on the musculoskeletal system, Mat Pilates might be an affordable option to improve muscle strength and flexibility, and the latter could aid joint mobility.
Although some studies [11,13] have been carried out with Pilates in BCS, research on the effects of Mat Pilates in BCS undergoing hormone therapy which includes a clear planned strategy to increment the exercise load and volume throughout the intervention was not found. The systematization of physical exercise (i.e., intensity, volume, sets, and exercise rest period) is fundamental to achieve better results [22]. Thus, the aim of the current study was to evaluate the effects of 24 weeks of Mat Pilates in BCS undergoing AI and SMRE therapy on lower and upper body muscle strength and flexibility. We hypothesized that structured training with Mat Pilates would improve muscle strength and flexibility.

Study design
The HAPiMat study is a 24 week randomized controlled clinical trial with BCS undergoing AIs or SMREs. Participants were required to provide written informed consent before the intervention and were randomized into the Mat Pilates training or supervised relaxation group (control group) stratified by hormone therapy type (AIs and SERMs). Randomization was carried out using the Excel V R program by persons not involved in the research. The assessments were carried out at baseline (T1), week 12 (T2), and week 24 (T3).
This study was approved by the University Ethics Committee in December of 2018 under protocol CAAE 01993118.1.0000.5402, conformed to the Helsinki Declaration, and was approved by the Clinical Trials Register under protocol RBR-3253dz. The recruitment started in February of 2019. The study protocol was published as a preprint with open access [23].

Subjects
A total of 1100 registered BCS were found, with a response rate 80.60%. This study was disclosed through social media and flyers in the Regional Cancer Hospital. BCS undergoing hormone therapy who had previously participated in research studies of our laboratory were also invited to participate. After applying the inclusion-exclusion criteria, 43 BCS were eligible (Figure 1). Participants were required to be �40 years, with confirmed breast cancer stage 0-III certified by a physician and stated in the medical record, be undergoing hormone therapy, have clearance from their physician to practice Mat Pilates and physical tests, live in or near the city where the research was carried out, not be currently practicing Pilates or any other regular resistance training, and sign the consent form. All participants were included in the intention to treat (ITT) analysis. For the per protocol analysis (PPA) participants were excluded if they begun any type of systematic training during the intervention or stopped hormone therapy (Supplementary materials).

Mat Pilates program
The intervention was held three times a week (60 min per session) by a qualified Mat Pilates instructor and an undergraduate on the Bachelor of Physical Education course, to better control each session (2:7). The difficulty and number of exercise repetitions were increased over the weeks, starting from beginner, followed by intermediate, and then advanced level (for some of the exercises). The participants continued at the same level of exercise in cases where they were not able to progress. As the participants acquired ease in performing the exercises, the degree of difficulty of the exercises was increased over the weeks, as well as the number of repetitions, respecting the participants' limitations. The Mat Pilates general planning and exercises (Table 1) were based on the Bertoli et al. [24] study.

Control group
Participants in the control group attended the university every 15 days for self-knowledge activities and relaxation techniques (Table 2). After every 45 min session, a mindfulness meditation was carried out [25].

Safety
The limitations of the participants to perform the exercise were respected. Participants were exempted of performing the physical tests if they had pre-existing musculoskeletal condition that could cause harm. Adverse events (i.e., muscle and joint pain, muscle soreness, dizziness) that occurred during the assessments and intervention were recorded.

Lower body resistance tests
Before testing, participants completed a warm up of 5 min of cycling at 50 W on a cycle ergometer (Ergo-fit 167 Cycle, Pirmasens, Germany). Hip flexor and extensor muscles were assessed with an isokinetic dynamometer (BIODEX Medical Systems 4, Shirley, NY). The same protocol used in Bertoli et al. [24] to position the participants was adopted. Once the participant was positioned in the dynamometer, a warm up was performed with 10 repetitions of the flexor-extensor muscle concentric contractions at 120 � s À 1 .
Subsequently, the isometric tests consisted of three contractions of 5 s and a fourth repetition was performed when the coefficient of variation was higher than 5%. The maximal isometric voluntary contractions (MIVC) for the flexor muscles were performed at 15 � of hip flexion, while for the extensor muscles, contractions were performed at 100 � [26]. After 2 min of rest, the isokinetic tests were performed at concentric/eccentric contractions for the flexor muscles at 30 � range of motion. For the extensor muscles, eccentric/concentric contractions were performed at 70 � range of motion. The angular velocity for both muscle groups was 60 � s À 1 with a 2 min rest between sets (two sets). Peak torque (PT) and mechanical work (MW) were normalized by the participant's body mass (Nm�kg À 1 and J�kg À 1 , respectively).

Upper body resistance test
Upper body strength parameters were evaluated only until week 12 due to mechanical problems with the equipment. The same protocol used in Bertoli et al.
[8] was also carried out in the current study. Three MIVC of 5 s (s) with a rest period of 90 s were performed with a load cell (Cefise n2000 pro 2.0) in the following muscle groups: (a) trunk extensors and (b) right and left shoulder abductors. For the trunk extensor muscles, participants were required to remain in the standing position with the knee and hip flexed at 120 � , the back and elbow in the extended position, and the trunk extended. The shoulder abductor muscles were assessed in a standing position at 65 � shoulder abduction [8]. The participants were instructed to perform the contractions as fast and hard as possible. A fourth MIVC was performed in case of a 5%  The time interval between exercises is given when changing the type of exercise, which involved a different muscle group or changing body position (lying in ventral, dorsal, or lateral decubitus, sitting with flexed or extended knees, kneeling, quadruped, or standing position). a Indicates that the same characteristic and sequence of the exercises are performed throughout the intervention described in the line of the week 1-24 (item a). b Indicates that the same characteristic and sequence of the exercises are performed throughout the intervention described in the line of the week 1-24 (item b). coefficient of variation between the attempts [27]. The highest MIVC was considered for analysis.
To compare the upper body resistance parameters, time to achieve maximal force (TF max ), and maximal force (F max ) normalized by body mass (F max �kg À 1 ) were evaluated. In order to obtain muscle power, the absolute rapid force index (RFI) was assessed, which was obtained by dividing absolute F max by the TF max (F max / t). [28] The F max �kg À 1 was divided by TF max to obtain the normalized RFI�kg À 1 [8]. A secondary analysis was carried out only for the intervention group, comparing the effect of Mat Pilates on upper body strength parameters between surgery and non-surgery sides.

Maximum isometric handgrip
The MIVC of the forearm muscle was assessed with an adjustable hand dynamometer (Standard Cefise dynamometer, Nova Odessa, Brazil) in the right and left hand. Participants remained in the sitting position with the back straight, and the hip and elbow flexed at 90 � [29]. Three intercalate contractions of each hand were performed until the participants achieved their MIVC with a twominute rest between attempts. The best result was used for analysis. The result was normalized by the participant's body mass (kgf�kg À 1 ).

Flexibility
According to Segal et al. [30], musculoskeletal flexibility is the capacity of muscles to move a body segment throughout its range of motion, which is considered a health component. The flexibility of the hip and hamstring muscles was assessed with the sit-and-reach test [31,32], while flexibility of the shoulder and triceps were evaluated with the back-scratch test [31]. Both right and left lower and upper body were analyzed. Two repetitions of each side were performed and the best one was used for analysis. Both the modified sit-and-reach and back scratch tests were measured in centimeters according to the Jones and Rikli [31] protocol. A secondary analysis was carried out only for the intervention group, comparing the effect of Mat Pilates on upper body flexibility between surgery and non-surgery sides.

Sample size
Given the primary outcomes, the study design (two groups and three repeated measures), and based on a previous study, which involved BCS undergoing hormone therapy [13], the sample size resulted in a minimum of 20 participants (group � time interaction), 20 participants (time), and 58 participants (between group analysis), taking into account an alpha error <.05, a non-sphericity correction e¼1, a correlation between the repeated measures ¼ 0.5, and a desired power (1b error)¼0.80 based on a small effect size (0.31). G � Power (University of D€ usseldorf, Dusseldorf, Germany) was used for the analysis.

Statistical analysis
Descriptive analysis was carried out. Baseline characteristics of the participants were compared (Pilates group versus control group) with the Student t-test, Chi-square, and Fisher's exact tests. Data normality was verified through the Shapiro-Wilk test. The generalized estimating equations (GEE) model was used to compare each outcome measure. Intention to treat analysis was used. A complementary analysis was performed only with those participants assigned to a treatment who actually received, complied with, and completed the intervention, PPA. The Bonferroni post hoc test was applied when significant differences were identified for the time. The effect size was calculated based on differences in groups with unequal sample sizes within a pre-post-control design, and classified according to Cohen [33], with <0.1 (adverse), 0.0-0.1 (no effect), 0.0-0.40 (small), 0.50-0.70 (intermediate), and �0.80 (large). SPSS 22.0 was used for the statistical analysis (SPSS Inc., Chicago, IL). To verify the impact of age and type of surgery on upper body strength parameters and flexibility, and the impact of age on lower body flexibility and torque parameters, repeated measure ANOVA (mixed model) was applied. Greenhouse-Geisser and Huynh-Feldt corrections were used when the measurements did not meet the sphericity assumption. These analyses were performed using Jamovi software (see Supplementary materials). Statistical difference was considered when p < 0.05.

Baseline participant characteristics
There were no statistical differences between Pilates and control groups at baseline for body weight, body mass index, and sociodemographic variables (Table 3). Plans and actions Learning how to elaborate plans and actions to achieve personal goals. 5 Assertive communication Learn about passive, aggressive, and assertive communication to achieve and maintain a good relationship with others. 6 Good communication Activities to comprehend the importance of good communication. 7 Good interpersonal relationship Reflecting how we influence and, at the same time how we are influenced by people's behavior (i.e., family, friends, and strangers). 8 "Dream balloon" Reflecting the importance of self-helping and helping others to conquer our own and others' dreams. 9 Popular quotations Learning and reflecting from popular quotations. 10 "Ship Factory" Understanding the importance of dialog, team work, and leadership development in the participants' life. 11 "Building Towers" Working on self-esteem, highlighting the importance of learning to trust the other to strengthen a good relationship. 12 "Affective Diploma" Reflecting on what the participants built and achieved during the intervention.

Hip torque parameters and handgrip strength (Table 4)
The isometric extensor muscles PT showed higher values for the intervention group compared to control at T2 and T3 (p ¼ 0.037 and p ¼ 0.013, respectively), with increments at T2 and T3 compared to T1 (p ¼ 0.013, and p ¼ 0.006, respectively). The isometric flexor muscles PT presented higher values for the intervention group at T3 compared to the control group (p < 0.001), with increments at T3 compared to T1 (p ¼ 0.04). The concentric flexor muscles PT showed greater values for the intervention group than control group at T2 and T3 (p ¼ 0.001, respectively), with increments at T2 and T3 compared to T1 (p ¼ 0.015; p ¼ 0.010, respectively). The eccentric flexor muscles PT showed higher values for the intervention group than control group at T3 (p ¼ 0.001), with increments at T3 compared to T1 (p ¼ 0.048). The concentric extensors MW showed higher values for the intervention group than control at T1 and T3 (p ¼ 0.006; p ¼ 0.037), with increments at T3 compared to T1 (p ¼ 0.023). The eccentric extensors MW showed higher values for the intervention group than control at T1 (p ¼ 0.005). The concentric flexor muscles MW revealed higher values for the intervention group than control at T3 (p ¼ 0.005), furthermore, during the eccentric contractions the intervention group presented higher values compared to control at T2 and T3 (p ¼ 0.002; p ¼ 001, respectively). The right handgrip strength presented higher values for the intervention group compared to control group at T3 (p ¼ 0.039).

Upper body force parameters (Table 5)
The intervention group presented improved left shoulder abductor TF max compared to the control group at T1 and T2 (p ¼ 0.003; p < 0.001, respectively), with increments at T2 compared to T1 (p < 0.001). The F max right and left shoulder abductor showed increments for the intervention group at T2 compared to T1 (p ¼ 0.011; p ¼ 0.016, respectively). The trunk extensor muscles F max showed increments for the intervention group at T2 compared to T1 (p ¼ 0.025), and was also higher for the intervention group compared to control at T2 in relation to T1 (p < 0.001). Left shoulder RFI showed higher values for the intervention group at T2 compared to control group, and significant increments at T2 compared to T1 (p < 0.001 respectively). (Table 5) TF max improved at T2 compared to T1 for non-surgery side and surgery side (p ¼ 0.029; p ¼ 0.023, respectively). F max of surgery side improved at T2 compared to T1 (p ¼ 0.002). RFI increased at T2 compared to T1 for both non-surgery and surgery sides (p ¼ 0.005; p ¼ 0.001, respectively).

Surgery side versus non-surgery side flexibility (Table 6)
The flexibility of the non-surgery side improved at T3 compared to T1 (p ¼ 0.010) in the back scratch test.

Discussion
The main finding of this study is that Mat Pilates was able to increase the majority of the BCS upper and lower body strength parameters and flexibility. Shoulder abductor muscles of the nonoperated side presented improved TF max and RFI, while the operated side presented improved TF max , F max , and RFI. The ITT and PPA showed similar behavior for all the assessed variables (Supplementary material).
Given the adverse effects of hormone therapy [34] and the residual effects of previous treatments [8, 35], increased muscle strength and power, which was measured by the RFI would provide BCS undergoing hormone therapy with better functional capacity performance and independence for daily life activities [11]. Moreover, as the life expectancy of this population has risen, the majority of these patients achieve old age, which is also affected by muscle contractile properties and associated with risk of falling [36]. Therefore, engagement in physical exercises that improve muscle strength could be a strategy to increase functional capacity among BCS. This is the first study to investigate the effect of Mat Pilates on hip flexor-extensor muscle torque variables in BCS undergoing hormone therapy, which showed increments in hip flexor-extensor muscles PT and MW in most of the assessed contractions. Mechanical work denotes the energy transmitted from one body segment to another to produce movement (i.e., locomotion); significant improvements in this parameter are extremely important due to its relation with activities of daily living [37]. Furthermore, hip muscles are involved in everyday tasks, such as recovering balance, avoiding stumbles, and climbing stairs [38,39].
After 12 weeks of intervention, the majority of the upper body strength variables improved in the Pilates group. Even though the treatment techniques for breast cancer surgery have improved significantly, most BCS experience adverse upper body effects, such as range of motion and muscle strength reduction, as well as chronic pain and sensorial disorder [40,41], which can remain several years after surgery [41] affecting activities of daily living [42], and return to work [43]. Therefore, the loss of muscle strength and range of motion decrements can negatively impact BCS quality of life [44]. In this scenario, exercise interventions, which increase range of motion and muscle strength, seem to be essential.
In the current study, increments in the RFI, which measures explosive force, were observed, which could be a sign of neural adaptations (i.e., cortical and subcortical adaptations increasing motoneuron activation) [45], an important aspect in this population given that breast cancer surgery and radiotherapy negatively impact the upper body and trunk muscles [46]. The surgery and non-surgery side (Pilates group only) did not differ between them after 12 weeks of intervention. Nonetheless, both sides enhanced TF max , F max , and RFI. These results could be related to activation of muscle satellite cells, which repair and regenerate muscle, due to the Pilates training [46], in which some of the exercises involve sustaining the body weight with the upper body.
In terms of exercise interventions, this is the first study to analyze the effect of Mat Pilates on trunk extensor muscle strength parameters in BCS undergoing hormone therapy. Most studies focused on shoulder range of motion [13,47,48], shoulder strength [13], and handgrip strength [13,47]. In this context, Zengin  Alpozgen et al. [13] evaluated the effects of eight weeks of Mat Pilates in BCS, with 40-45 min each session, three times per week, comparing the Pilates group with a combined exercise group and a home-based group. The combined exercise consisted of stretching, range of motion, and shoulder exercise. The same exercises were selected for the home-based group, with supervision carried out by a phone call every 10 days. The authors found out that both Pilates and combined exercise groups significantly improved shoulder abductor, flexor, and internal rotator muscle strength during the isometric contraction of the affected limb, while the home-based group presented increased shoulder abductor and flexor muscle strength. Moreover, the Pilates group presented greater increments compared to the combined exercise and home-based group. However, Zengin Alpozgen et al. [13] do not describe the number of repetitions and sets performed in the Pilates group. As been said, despite the fact breast of cancer surgeries techniques have improved, upper body flexibility is also affected [40,41]. In this study, right-left upper body flexibility improved after 12 weeks, with maintenance after 24 weeks of intervention in the Pilates group. The upper body flexibility assessment, performed in this study, involves shoulder mobility and triceps flexibility [31]. A systematic review and meta-analysis showed that Pilates increased shoulder range of motion [49], nonetheless, the studies had fewer exercise sessions and did not delimit the sample for BCS undergoing hormone therapy only. When separated by surgery side, upper body flexibility demonstrated significant differences after the intervention for the non-surgery side only.
A recent investigation [48] analyzed the effects of 16 weeks of Mat Pilates compared to a belly dance group and a control group in BCS undergoing hormone therapy (AIs and TMX). Both Mat Pilates and belly dance programs had a duration of 16 weeks, performed three times per week, with 60 min per session, while the control group was instructed to perform stretching exercises at home. All groups presented improved shoulder range of motion in flexion movement of the right side; however, the Pilates group achieved greater increments. Although the protocol of Leite et al. [48] had a shorter duration, and the number of repetitions was not specified, it has some similarities compared to this study. The authors divided the Pilates sessions into three components (warm up, main component, and cool down or relaxation), and they also added elastic bands, Pilates ball and extra weight in order to increment the exercise load. Leite et al. [48] observed increments in the belly dance group shoulder range of motion [48], which could be due to exercises of flexion, extension, abduction, adduction, and rotation of the shoulder in the warm up component, while the control group was taught to perform stretching exercises at home to prevent lymphedema.
Although lower body flexibility is not affected by breast cancer treatments, physical inactivity is common among BCS [50], which could cause poor low back, hip, and thigh flexibility. Our study showed improvements in lower body flexibility after 12 weeks of intervention, with maintenance after 24 weeks of intervention for the Pilates group. Moreover, some studies have shown that hormone therapy caused joint stiffness [7,51], and in this scenario the Pilates method could be a great ally to improve joint range of motion.
A recent study [52] assessed the effects of eight weeks of Mat Pilates, performed twice a week for 75 min per session on lower body flexibility in BCS. The Mat Pilates group was compared to a circuit-based exercise group, which performed aerobic, strength exercises, joint mobility, and global stretching twice a week for 75 min per session, and to a control group. Nonetheless, not all   the participants were undergoing hormone therapy. Lower body flexibility was measured through the sit and reach test, which showed improvements for the Mat Pilates group only. Overall, the conditions used in this training protocol are sufficient for BCS with low mobility to achieve a better level of physical functional capacity. In terms of muscle strength, some previous findings highlighted that low levels of upper body strength can be a limitation to daily tasks [49,53]. Conversely, encouraging BCS to be physically active (e.g., carry bags and transfer objects up to down, and vice-versa) should be an integral part of the principles of a systematized physical exercise program for these patients.
Furthermore, Mat Pilates can be practiced not only at the gym facility, but also in different environments, such as at home, at the park, or at the hospital where BCS are receiving treatment. Another aspect, for instance, socialization, and the need for a minimum amount of equipment to practice Mat Pilates exercises make this modality attractive for this population, and it can be added as a part of an exercise program including other type of exercise (i.e., aerobic training or weight lifting) on non-consecutive days. The Pilates method is characterized as being a mindbody exercise connecting breathing with concentration during each movement [54], which is in line with some of the mindfulness principles [55]. Although mindfulness was included only for the control group, greater results might be achieved in BCS while practicing Pilates in terms of fatigue, anxiety, and depression. Further studies involving Pilates and Mindfulness simultaneously are needed.

Limitations
The strengths of this study are: (a) being the first to analyze hip flexor-extensor muscles in different contractions after an exercise intervention in BCS undergoing hormone therapy and (b) exercise planning throughout the intervention (i.e., volume, intensity, and exercise level progression). However, some limitations must be acknowledged: (a) lack of blinding assessments, (b) not performing upper body assessments after 24 weeks of the intervention, (c) the exercise intensity was not controlled by the rate of perceived exertion, which could have led to greater outcome increments, and (d) although muscle strength and flexibility increased, we cannot infer the impact of these results on quality of life and cancer control. That being said, further investigations comparing structured and non-structured Pilates programs could be carried out to confirm the effects of Mat Pilates on muscular strength and flexibility not only in BCS cancer survivors undergoing hormone therapy, but also in other types of cancer survivors and stages of treatment.

Conclusions
From our findings, it was observed that 24-weeks of Mat Pilates induced PT increments in the intervention group during the isometric contractions of the extensor-flexor hip muscles, and during the concentric-eccentric contractions of the hip flexors. Mechanical work increased after 24 weeks of intervention during the concentric contraction of the extensor-flexor hip muscles, and during the eccentric contraction of the hip flexors. On the other hand, 12-weeks of Mat Pilates induced upper body strength parameter increments for all the assessed variables (TF max , F max , and RFI) in most of the analyzed upper body muscle groups. Finally, right-left upper and lower body flexibility increased after 12 and 24 weeks of intervention.