Muscle Function Analysis of the Pilates Teaser in Pilates Practitioners

Yu, Jiye; Kim, Changsun; Jiye Yu; Changsun Kim

doi:10.15857/ksep.2025.00325

Exerc Sci > Volume 34(2); 2025 > Article

Yu and Kim: Muscle Function Analysis of the Pilates Teaser in Pilates Practitioners

Original Article

Exerc Sci.. 2025; 34(2): 217-226.

Published online: May 30, 2025

DOI: https://doi.org/10.15857/ksep.2025.00325

Muscle Function Analysis of the Pilates Teaser in Pilates Practitioners

Jiye Yu MS

, Changsun Kim PhD

Department of Physical Education, Dongduk Women's University, Seoul, Korea

Corresponding author: Changsun Kim Tel +82-2-940-4507 Fax +82-2-940-4502 E-mail chang@dongduk.ac.kr

*This work was supported by the Dongduk Women's University grant.

Received May 15, 2025 Revised May 21, 2025 Accepted May 23, 2025

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

PURPOSE

The purpose of this study was to investigate the muscle function involved in the Pilates Teaser.

METHODS

A total of 22 middle-aged women (10 in the Pilates group [PG] and 12 in the non-Pilates group [NPG]) participated in this study. During the Pilates Teaser, the hip joint angle was measured along with assessments of muscle thickness, muscle activation, and muscle fatigue. Isometric muscle strength was evaluated separately. Additionally, functional movement and dynamic balance were evaluated using the Functional Movement Screen (FMS) and the Y-Balance Test (YBT).

RESULTS

The women in PG maintained a significantly smaller hip joint angle than NPG (p<.01), indicating a more precise execution of the Pilates Teaser. In muscle thickness, PG showed significantly greater thickness in the rectus abdominis (p<.01), external oblique (p<.001), and rectus femoris (p<.01). Regarding muscle activation, PG exhibited significantly lower %MVC values in the rectus abdominis (p<.05) and external oblique (p<.05), and muscle fatigue in the rectus abdominis was significantly lower in PG (p<.05). In the FMS assessment, PG outperformed NPG in Deep Squat (p<.05), Hurdle Step (p<.05), Inline Lunge (p<.01), and Rotary Stability (p<.001), with significantly higher total scores (p<.001). However, no significant differences were observed between the two groups in isometric muscle strength and dynamic balance.

CONCLUSIONS

These findings suggest that consistent Pilates training enhances muscle thickness, muscle activation efficiency, and fatigue resistance, ultimately strengthening the powerhouse and facilitating more precise execution of the Pilates Teaser.

Keywords: Pilates, Teaser, Muscle thickness, Muscle activation, Muscle fatigue

INTRODUCTION

Pilates is an exercise method that emphasizes harmonious movement and functional improvement [1], with a growing interest owing to its fo-cus on core muscle activation [2]. Developed in the early 20th century by Joseph Pilates in Germany, this method is based on six fundamental principles: breathing, concentration, control, centering, precision, and flow [3]. Among these, centering contributes to physical stability and coordination by engaging the “ powerhouse,” which includes the abdomen, pelvis, and the base of the spine [4].

The Pilates Teaser, a representative movement that strengthens the powerhouse, requires full-body coordination and balance. It involves the simultaneous movement of the upper and lower limbs while controlling the body around the core [5]. This movement can reveal differences in performance depending on Pilates proficiency. Previous studies have reported that the surface type and skill level significantly influence core stability and muscular balance during the Pilates Teaser [6]. In particular, experienced practitioners were able to maintain stable postures even on soft surfaces, suggesting a more effective coordination of the trunk muscles. Despite the importance of the Pilates Teaser as a core-focused movement and the potential variability by experience, studies specifically examining this exercise remain limited.

The evaluation of muscle function is essential to quantitatively assess the effects of Pilates. Muscle thickness is a key indicator of muscle function assessment [7] and is generally highly correlated with muscular strength [8]. Muscle thickness can be measured using magnetic reso-nance imaging (MRI), computed tomography (CT), or ultrasonography. Although MRI provides a high-resolution analysis, it is limited by its cost and accessibility [9]. In contrast, ultrasound is a noninvasive, eco-nomical, and repeatable method that is widely used in exercise science research owing to its reliability [10]. A recent study using dual ultrasonography and shear wave elastography showed that muscle thickness is significantly associated with strength in older adults with hypertension and sarcopenia [11].

Electromyography (EMG) is a useful tool for assessing muscle activation during exercise [12]. This can be performed by using intramuscular or surface electrodes [13]. Surface electromyography (sEMG) is a noninvasive method that measures the electrical activity of muscles through electrodes attached to the skin. It allows for quantitative analysis of neuromuscular responses, is suitable for repeated measurements, and offers real-time feedback [13,14]. The sEMG is widely used to objectively con-firm whether Pilates movements effectively target the intended muscles. EMG has been used to examine the activation of trunk stabilizer muscles, such as the multifidus and iliocostalis lumborum, during core-focused exercises [15]. Seo et al. (2025) quantitatively measured shoulder muscle activation using sEMG during Pilates exercises and analyzed how spring tension influenced muscle activation and intermuscular coordination [16]. However, few studies have investigated the activation of powerhouse muscles, specifically during the Pilates Teaser.

Muscular strength is a core component of daily movement and physical fitness and is a key determinant of athletic performance [17]. Core strength contributes to trunk stability and provides an efficient support base for limb movement [18]. Pilates is considered an effective intervention strategy for enhancing functional performance and exercise adher-ence through low-intensity repetitive movements that improve core support strength [19]. Improvements in strength are also associated with increases in muscle thickness [20], and the repetitive and precise nature of Pilates exercises can significantly contribute to the development of core strength. Although previous research has shown that Pilates improves postural alignment, strength, and flexibility [21], most studies have focused on pre- and post-exercise comparisons, with limited analysis of physiological indicators during the Pilates Teaser.

Functional movement and dynamic balance are important components of physical performance. These can be evaluated using the Functional Movement Screen (FMS) and the Y Balance Test (YBT), respectively. The FMS assesses basic movement patterns and is used to evaluate core stability and whole-body coordination as well as to screen for injury risk [22]. This is considered a useful indicator to indirectly verify the effects of core-focused exercise programs. In a systematic review by Saçlı and Çatalbaş (2025), Pilates significantly improved overall FMS scores, with core strengthening contributing to better control and accuracy across all seven subtests [23]. The YBT is effective in assessing dynamic balance and movement asymmetry [24], and is considered a valid measure for evaluating whole-body coordination and balance among Pilates practitioners. Jiang et al. (2022) also confirmed that YBT is an effective tool for detecting changes in dynamic balance following Pilates-based balance training [25].

Therefore, the present study aimed to analyze the effects of Pilates on core-related muscle function by comparing muscle strength, muscle thickness, muscle activation, and fatigue during Pilates Teaser movements between experienced and inexperienced practitioners. In addition, we investigated the differences in functional movement and dynamic balance according to Pilates proficiency to provide evidence for the value of Pilates as a movement-based intervention strategy.

METHODS

1. Participants

This study included 22 healthy middle-aged women between the ages of 40 and 64. Participants were divided into two groups: a Pilates group (PG, n=10), composed of individuals who had participated in a Pilates program at least twice a week, one hour per session, for a minimum of 8 weeks over the past 6 months, and a non-Pilates group (NPG, n=12), consisting of individuals with no prior experience in Pilates. The PG was defined as individuals who had participated in regular Pilates classes at least twice a week for the past six months or longer, with an average Pilates experience of 9.3±6.1 years.

An a priori power analysis was conducted using G*Power 3.1.9.7. With an effect size of 0.6, a significance level (α) of .05, and a power of .85, the required minimum sample size was calculated to be 22 participants.

This study was conducted in accordance with the ethical principles of the Declaration of Helsinki, ensuring the protection of participants’ rights. All participants were fully informed of the purpose and procedures of the study prior to participation, and only those who provided written informed consent were included in the study.

All participants were informed of the purpose and procedures of the study, and voluntarily agreed to participate. The inclusion criteria required participants to be free from musculoskeletal injuries (e.g., fractures, ligament, or muscle damage) and cardiovascular diseases within the past 6 months. Patients with other medical conditions were excluded.

The general characteristics of the participants are presented in Table 1.

Table 1.

Subject Characteristics

	NPG	PG	t	p
Age (yr)	56.1±4.5	49.1±7.6*	2.551	.023
Height (cm)	160.2±3.7	162.5±3.7	-1.423	.170
Weight (kg)	59.9±5.6	57.4±5.6	1.028	.316
SMM (kg)	21.7±1.65	22.5±2.84	-0.872	.393
BFM (kg)	19.7±4.1	15.7±3.6*	2.439	.024
PBF (%)	32.7±4.6	27.3±5.4*	2.549	.019
AMM (kg)
R Arm	1.99±0.23	1.96±0.26	0.218	.830
L Arm	1.96±0.21	1.97±0.26	-0.036	.971
Trunk	18.1±1.34	18.1±1.65	0.071	.944
R Leg	6.18±0.60	6.42±0.86	-0.766	.452
L Leg	6.19±0.57	6.43±0.88	-0.768	.452

Mean±SD. NPG, non pilates group; PG, pilates group; SMM, skeletal muscle mass; BFM, body fat mass; PBF, percent body fat; AMM, appendicular mus cle mass; R Arm, right arm; L Arm, left arm; R Leg, right leg; L Leg, left leg.

2. Procedures

1) Pilates teaser assessment

The participants began in the supine position, with both arms resting comfortably on the floor. During exhalation, the participants lifted their upper body and held the Pilates Teaser position for 3 seconds as shown in Fig. 1, and then inhaled and completed the movement with a controlled exhalation.

Fig. 1.

Measurement of hip joint angle during the teaser movement.

To assess the hip joint range of motion during the Pilates Teaser, a standard goniometer (Lafayette Extendable Goniometer, Model 01135) was used to measure hip flexion. The knee joints were extended and the goniometer axis was aligned with the femoral head. The angle between the longitudinal axis of the femur and a line parallel to the trunk was measured (Fig. 1). Each participant performed the Pilates Teaser movement five times. The highest and lowest values were excluded and the average of the remaining three values was used as the final value.

2) Muscle thickness measurement

Muscle thickness was measured using a portable ultrasound device (SONON 300 L; Healcerion, Seoul, Korea). Four muscles involved in the powerhouse were assessed using the Pilates Teaser: the rectus abdominis (RA), external oblique (EO), rectus femoris (RF), and multifidus (MF). The measurements were precisely conducted to the nearest 0.1 mm following zero-point calibration in accordance with the manufacturer's manual for the device. All subsequent assessments were consistently performed by a single experienced researcher specialized in the field of kinesiology.

The measurement protocols are illustrated in Fig. 2. The RA was assessed 3 cm lateral to the umbilicus in the supine position [26]. The EO was measured 25 mm medial to the midpoint between the 12th rib and the iliac crest [27]. For MF, the spinous processes of L4-L5 were palpated, and the probe was placed perpendicular to the midline of the spine. The probe was then tilted medially until the zygapophyseal joints were clearly visualized, and the thickness was measured at the point of maximum visibility [28]. The RF was measured at the midpoint of the line connecting the superior pole of the patella and the anterior superior iliac spine (ASIS) [10].

Fig. 2.

Electrode placement sites for measuring muscle thickness, activation, and fatigue using surface electromyography. RA, Rectus Abdominis; EO, External Oblique; RF, Rectus Femoris; MF, Multifidus.

3) Muscle activation and fatigue

Muscle activation during the Pilates Teaser was assessed using a surface EMG system(Mini DTS Receiver, NORAXON, USA) at the same locations used for muscle thickness assessment (Fig. 2). The target muscles included the rectus abdominis (primary trunk flexor), external oblique (primary lateral flexor), rectus femoris (primary knee extensor), and multifidus (primary trunk extensor) [28,29]. All electrodes were attached to the right side of the body in accordance with standardized guidelines [30,31].

The EMG signals were normalized to the maximum voluntary contraction (MVC) of each muscle, and activation was expressed as %MVC using the following formula:

Standardized EMG (%MVC)=(Measured EMG/MVC EMG)×100.

For fatigue analysis, the participants performed the Pilates Teaser for 40 seconds. The middle 30 seconds of the EMG data, excluding the first and last 5 seconds, were analyzed to account for movement stabilization. Fatigue indices were calculated using the MR3 3.8 software (Noraxon Inc., USA).

4) Muscle strength

The maximal isometric strength was assessed using a handheld dyna-mometer (microFET2, Hoggan Scientific, LLC, USA). Each test was performed three times following two practice trials, and the average of the three trials was used for the analysis. Force values were recorded in pounds (lb) and converted to kilograms (kg). A rest interval of 30 seconds was provided between measurements, and all tests were performed within a pain-free range of motion [32].

Strength was assessed in the trunk flexors, lateral trunk flexors, knee extensors, and trunk extensors (Fig. 3).

Fig. 3.

Isometric strength assessment positions for trunk flexion, trunk lateral flexion, leg extension, and trunk extension. Arrows indicate directions of force application: ⓐ examiner; ⓑ participant.

5) Functional movement screen (FMS)

Functional movement was assessed using the FMS (USA) developed by Gray Cook and colleagues, which consists of seven movement tasks (Fig. 4) [33]. The deep squat assessed movement in the lower extremities and shoulders as well as bilateral symmetry. The hurdle step was used to evaluate ankle, knee, and hip function and stability. The inline lunge assesses overall body movement, joint stability, and balance. The shoulder mobility task measured bilateral shoulder rotations. The active straight leg raise assessed the flexibility of the knee flexors. The trunk stability push-up was used to evaluate core stability, and rotary stability was used to assess the rotational control of the upper body, lower body, and trunk.

Fig. 4.

Comparison of hip flexion angles between NPG and PG during the teaser movement. Mean±SD; NPG, non pilates group; PG, pilates group.

Participants were thoroughly instructed on their movements and scoring methods. For tests involving both the left and right limbs, the left side was assessed first in accordance with standard FMS protocols. Each task was scored on a 4-point ordinal scale from 0 to 3:3 points: performed movement without compensation; 2 points: completed movement with compensation; 1 point: unable to complete the movement; and 0 points: pain during movement. The maximum total FMS score was 21 points.

6) Y-Balance test

Dynamic balance of the lower extremities was assessed using a Y-Balance Kit (Move2Perform, Evansville, IN, USA). After a detailed explanation and demonstration, each participant performed 2-3 practice trials before testing.

The participants stood on one leg while reaching in three directions with the opposite leg: anterior, posteromedial, and posterolateral. Each direction was tested thrice, and the farthest reach in each direction was recorded.

To allow a relative comparison, the reach distance was normalized to leg length. Leg length was measured from the ASIS to the medial malle-olus using a tape measure while the participants stood upright [34]. The normalized reach distance was calculated using the following formula:

Normalized Reach Distance (%NRD)=Reach Distance÷Right Leg Length×100

3. Statistical analysis

All data were analyzed using SPSS software (version 25.0; IBM Corp., Armonk, NY, USA). Descriptive statistics are presented as mean±stan-dard deviation (SD). Independent sample t-tests were used to compare differences between groups. The significance level for all analyses was set at α=.05.

RESULTS

1. Hip angle during the pilates teaser

During the Pilates Teaser, the hip flexion angle was significantly smaller in PG (99.6±20.8°) compared to NPG (127±14.3°) (Fig. 4), representing a 21.6% reduction in PG (p <.01).

2. Muscle thickness

During the Pilates Teaser, RA thickness was significantly greater in PG (19.0±1.4 mm) than in NPG (12.8±3.6 mm), an increase of 48.4% (p <.001). EO thickness was also significantly greater in PG (11.8±2.0 mm) compared to NPG (8.1±1.7 mm), a 45.7% increase (p <.001). RF thickness was 20.7±3.8 mm in PG and 15.2±4.4 mm in NPG, a 36.2% increase in PG (p <.01). No significant difference was observed in the MF (p =.055) (Fig. 5).

Fig. 5.

Comparison of powerhouse muscle thickness between NPG and PG during the teaser movement. Mean±SD. NPG, non pilates group; PG, pilates group; RA, Rectus Abdominis; EO, External Oblique; RF, Rectus Femoris; MF, Multifidus. ** p<.01, *** p<.001.

3. Muscle activation and fatigue

1) Muscle activation

RA activation was significantly lower in PG (81.3±23.6) compared to NPG (114.5±13.4), a 29% decrease (p <.01). EO activation was also significantly lower in PG (69.4±34.0) than in NPG (110.4±45.9), a 37.1% decrease (p <.05). No significant differences were observed in the RF or MF (Fig. 6).

Fig. 6.

Comparison of powerhouse muscle activation between NPG and PG during the teaser movement. Mean±SD. NPG, non pilates group; PG, pilates group; RA, Rectus Abdominis; EO, External Oblique; RF, Rectus Femoris; MF, Multifidus. * p<.05, ** p<.01.

2) Muscle fatigue

RA fatigue was significantly lower in PG (-5.0±6.4%) than in NPG (-7.9±5.3%), a 36.7% decrease (p <.05). No significant differences were observed in the EO, RF, or MF (Fig. 7).

Fig. 7.

Comparison of powerhouse muscle fatigue between NPG and PG during the teaser movement. Mean±SD. NPG, non pilates group; PG, pilates group; RA, Rectus Abdominis; EO, External Oblique; RF, Rectus Femoris; MF, Multifidus. * p<.05.

4. Muscle strength

Table 2 presents the isometric strength values measured using the Mi-croFET2. No significant differences were found between NPG and PG for TF, TLF, LE, or TE.

Table 2.

Comparison of isometric strength between NPG and PG (kg)

	NPG	PG	t	p
TF	18.9±4.0	20.0±4.2	-0.651	.523
TLF	16.0±3.5	16.8±4.3	-0.511	.615
LE	24.9±5.5	23.5±5.6	0.576	.571
TE	11.3±2.5	10.7±2.5	0.575	.572

Mean±SD. NPG, non pilates group; PG, pilates group; TF, trunk flexion; TLF, trunk lateral flexion; LE, leg extension; TE, trunk extension.

5. Functional movement

Significant differences were observed in the FMS Total Score (p <.001) and individual items, including Deep Squat (p <.05), Hurdle Step (p <.05), Inline Lunge (p <.01), and Rotary Stability (p <.001) (Fig. 8).

Fig. 8.

Comparison of Functional Movement Screen between NPG and PG. Mean±SD. NPG, non pilates group; PG, pilates group. * p <.05, ** p<.01, *** p<.001.

6. Dynamic balance

No significant differences were found between the NPG and PG in the anterior (AT), posteromedial (PM), or posterolateral (PL) reach directions in the Y-Balance Test. Table 3 presents the results of the study.

Table 3.

Comparison of Dynamic Balance between NPG and PG (%)

		NPG	PG	t	p
AT	R	75.8±7.0	73.4±9.7	0.469	.524
AT	L	79.9±9.0	79.5±12.5	-0.135	.933
PM	R	120.6±11.0	115.9±14.0	0.560	.389
PM	L	125.0±11.4	121.3±17.4	0.357	.562
PL	R	122.9±12.8	113.3±14.1	1.442	.110
PL	L	123.6±12.4	118.8±14.4	0.579	.415
TOTAL	R	106.4±9.0	100.9±10.8	0.205	.205
TOTAL	L	109.5±8.8	106.5±13.5	0.548	.548

Mean±SD. NPG, non pilates group; PG, pilates group; AT, anterior; PM, posteromedial; PL, posterolateral.

DISCUSSION

The significantly smaller hip flexion angle observed in PG during the Pilates Teaser (p<.01) suggests that this group was able to perform movement with greater accuracy and maintain a stable position at a higher el-evation. The Pilates Teaser involves concentric trunk flexion followed by eccentric extension, and its ability to maintain a static posture at the peak of movement reflects high-level trunk control. This indicates that PG had superior control and static stability during this challenging phase.

This postural control is closely associated with structural adaptations of the core musculature. Muscle thickness is a key indicator reflecting structural adaptations of muscles in response to training. It is widely used to evaluate exercise effects and to monitor long-term changes following interventions [35]. Therefore, assessing muscle thickness in experienced individuals who have performed Pilates over an extended period holds significant value in determining whether such training has in-duced structural adaptations. Ultrasound-based muscle thickness analysis revealed significantly greater RA, EO, and RF thicknesses in the PG (p <.05), likely because of repeated and sustained resistance stimuli through bodyweight-bearing movements. Similarly, Batıbay et al. (2020) reported that eight weeks of mat Pilates significantly increased the thickness of the core muscles, including the rectus abdominis, transversus abdominis, external oblique, and multifidus muscles, in women with chronic low back pain [36]. This supports the idea that continuous Pilates training promotes structural adaptations that contribute to muscle strength and stabilization of the powerhouse.

Previous studies have primarily focused on the transversus abdominis when analyzing changes in muscle thickness after Pilates training [37,38]. However, this study also observed significant increases in the RA, EO, and RF. These findings suggest that Pilates induces structural adaptations not only in deep core stabilizers, but also in superficial muscles through repetitive, functional movement patterns.

In contrast, no significant difference was observed in MF thickness between the groups. This may be because the measurements were taken at the peak of the Pilates Teaser, where the MF, which is primarily involved in intervertebral stabilization rather than gross movement, may not have been as active. Anatomically, the multifidus contributes to segmental stability rather than large-scale spinal motion such as extension or rotation [39]. It is known to be activated more during transitions than during static postures [40]. Therefore, the timing of the measurement at the peak may explain the lack of a significant difference.

The EMG analysis in this study revealed that the Pilates group exhibited significantly lower activation levels in the rectus abdominis and external oblique muscles (p <.01). This finding suggests not merely a reduction in muscle usage, but rather an enhancement in neuromuscular efficiency (NME), as the same posture was maintained with less muscular activation.

Similar trends have been reported in previous studies. For instance, after six weeks of isometric core training twice per week, a significant decrease in EMG activity was observed in key core muscles such as the rectus abdominis and internal oblique. This was interpreted as an adaptive response of the neuromuscular system, reflecting improved efficiency through repeated training [41]. Additionally, studies comparing Pilates practitioners and non-practitioners have shown that during trunk flexion tasks, the practitioner group exhibited significantly lower EMG responses than the non-practitioner group, indicating that Pilates training contributes to more efficient regulation of muscle activation strategies [42]. In this context, the significantly lower EMG values observed in the core muscles of the Pilates group during the Teaser movement in the present study further support the notion that Pilates experience is closely associated with enhanced neuromuscular efficiency.

No significant differences were observed in the RF activation. Although the RF is part of the powerhouse, it functions more as a synergist during hip flexion in the Pilates Teaser than as a primary stabilizer. The lack of group differences suggests that the PG relies less on compensato-ry muscles and more on the primary core musculature.

In terms of muscle fatigue, the PG exhibited significantly lower fatigue than the RA (p <.05), indicating greater muscular endurance and resistance to fatigue. During Pilates Teaser, the RA acts as the primary trunk flexor, requiring sustained isometric contraction [43]. These findings suggest that the participants in the PG developed enhanced metabolic efficiency, recovery capacity, and neuromuscular adaptation through Pilates.

In this study, no significant differences were found in isometric strength between the Pilates and non-Pilates groups. This may be due to the nature of Pilates, which emphasizes core stability and postural alignment rather than maximal strength gains, providing stimuli that are more specialized for postural control and muscular endurance.

While numerous studies have demonstrated that resistance training produces clear and significant improvements in muscle strength [44], other research has reported that Pilates does not show statistically significant advantages in strength enhancement compared to other exercise modalities [45]. These findings highlight the importance of selecting ap-propriate exercise methods based on the intended training outcomes. When improving muscular strength is the primary goal, exercise programs that include explicit resistance loading may be more effective than Pilates alone.

The FMS results showed that the PG had significantly higher Total Scores (p <.001), along with improvements in Deep Squat, Hurdle Step, Inline Lunge, and Rotary Stability (p <.05, p <.001). These items are closely associated with trunk stability and coordinated lower-limb movements. A lack of core control often leads to functional limitations in these tasks [46]. Rotary Stability, in particular, reflects trunk symmetry and segmental control [47], and the improved scores in the PG likely re-sulted from continued activation and enhancement of the powerhouse musculature. Previous studies on college-aged women also reported improvements in trunk and rotary stability after Pilates training, whereas no significant changes were observed in shoulder mobility [48]. This finding supports the idea that Pilates improves functional movement primarily through enhanced core control. These results align with the findings of Saçlı and Çatalbaş (2025), who concluded that Pilates improves overall FMS scores and enhances movement precision through core strengthening across all seven FMS domains [23]. Collectively, these findings suggest that improved core muscle control plays a critical role in maintaining postural alignment and stability.

On the other hand, no significant differences were observed in the Y-Balance Test. Previous studies have also interpreted the limited improvement in YBT performance through Pilates as a result of dynamic balance being more closely related to distal lower limb control than to core stability [25]. The YBT particularly demands fine motor control of the distal lower limbs, such as the ankle, and there are reports indicating that the eccentric torque control of the tibialis anterior plays a key role in YBT performance [49]. These findings suggest that core-focused exercis-es like Pilates may not fully translate into improvements in dynamic balance and that their effectiveness may vary depending on the type and purpose of the training. Therefore, in cases where lower limb balance is essential, such as fall prevention or gait improvement, it may be neces-sary to incorporate additional lower limb balance training into conventional Pilates programs.

CONCLUSION

This study examined the effects of sustained Pilates training on hip joint mobility, muscle thickness, muscle activation, and muscle fatigue during the Pilates Teaser movement by comparing experienced and inexperienced participants. The results showed that PG maintained a smaller trunk flexion angle and demonstrated significantly greater muscle thickness in the RA, EO, and RF. Additionally, the PG exhibited significantly lower muscle activation (%MVC) in the RA and EO, and lower fatigue in the RA.

FMS performance, including Total Score, Deep Squat, Hurdle Step, Inline Lunge, and Rotary Stability, also significantly improved in the PG. These findings suggest that regular Pilates training leads to both structural and functional improvements in the powerhouse muscles and enhances functional movement performance through the Pilates Teaser.

Notes

CONFLICT OF INTEREST

The authors declare that they have no competing interests.

AUTHOR CONTRIBUTIONS

Conceptualization: J Yu, C Kim; Data curation: J Yu, C Kim; Formal analysis: J Yu, C Kim; Funding acquisition: J Yu, C Kim; Methodology: J Yu, C Kim; Project administration: J Yu, C Kim; Visualization: J Yu, C Kim; Writing - original draft: J Yu, C Kim; Writing - review & editing: J Yu, C Kim.

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