Four weeks of exercise regimen for sedentary workers with rounded shoulder posture: a randomized controlled study

ABSTRACT BACKGROUND: Rounded shoulder (RS) posture causes neck and shoulder pathologies. Mechanical correction taping (MCT) is often incorporated into postural corrective therapies; however, its effects on muscle stiffness are unclear. OBJECTIVE: We investigated the effect of MCT with different tape fabrics, along with exercise, on upper trapezius and pectoralis minor muscle stiffness and the posture of sedentary workers. DESIGN AND SETTING: A randomized controlled study was performed at Aydın Adnan Menderes University, Aydın, Turkey. METHODS: The study included 39 workers with RS posture. Two intervention groups (performance tape: PT and classic tape: CT) were taped twice a week and administered a home exercise program for 4 weeks. The control (C) group performed only home exercises. RS was measured using an acromion-testing table (AT), stiffness using shear wave elastography ultrasound, and shoulder angle (SA) using a smartphone application at baseline and 4 weeks. Time and group interactions were determined using 3 × 2 mixed analysis of variance. RESULTS: Intragroup analyses revealed a significant main effect of time on AT distance (η2 = 0.445) and SA (η2 = 0.325) in the PT and C groups (P < 0.05) and left upper trapezius stiffness (η2 = 0.287) in the CT and C groups (P < 0.05). In the post hoc analyses, no difference was noted between the groups from baseline to 4 weeks (P > 0.05). CONCLUSION: Scapular MCT added to postural exercises did not show any difference between the intervention groups and controls in terms of muscle stiffness and posture in sedentary workers.

on shoulder muscle stiffness using the shear wave elastography method. Therefore, it remains unclear whether corrective taping regulates muscle stiffness in the long term.

OBJECTIVE
Our primary hypothesis was that MCT applied in addition to exercise would decrease the stiffness of the upper trapezius and pectoralis minor muscles and fix shoulder posture in workers with RS deformity. The secondary aim of this study was to determine whether different tape fabrics affected the application results.

Participants
This study was conducted at a university hospital with 45 sedentary workers aged 18-34 years. Participants were included if they had RS posture with reference to a prior screening using lateral acromion-testing table distance (AT distance) measurement. Based on the results of this test, individuals with a result of 3 cm or more were considered to have RS posture, as shown in a previous study. 9,20 The participants were excluded if they had a musculoskeletal system injury in the past 6 months or any neurologic or orthopedic disorder or cervical radiculopathy, received physical therapy in the last 6 months, participated in professional sports, or had an allergic skin reaction to the tape material. All procedures were explained to the participants, and written informed consent was obtained. Ethical approval for the study was obtained from the Ethics Committee of Aydın

Study design
This study was a randomized controlled, single-blinded clinical study. The participants were randomized using a computerassisted randomization method. For this process, the sequence generator available at "www.random.org" was used. The participants did not have any information about the groups formed or which group they belonged to. Therefore, a single-blinded study was performed. The study included two intervention groups, classic tape (CT, n = 15) and performance tape (PT, n = 15), and one control group (C, n = 15). Data were collected using a smartphone-based photographic analysis application, Dr. Goniometer (CDM S.r.L, Milano, Italy), for shoulder angle (SA) and using shear wave elastography for muscle stiffness.
Elastographic evaluations of the participants were performed by a radiologist at the Radiology Department of the same university. Worker height (cm), weight (kg), and age (years) were recorded as demographic information.

Sample size
Assuming that a strong degree of effect size (f = 0.5) was obtained for the difference between the three groups as a result of the power analysis conducted a priori in the direction of hypothetical expectations with reference to a similar study, 9 at least 42 individuals (14 for each group) were required to obtain 80% power with 95% confidence.

Intervention procedures
At the first visit, all the participants underwent baseline measurements. Immediately after the first visit, the tape was applied to the participants in the CT and PT groups. CT is a classical corrective tape made with a regular corrective fabric. PT is a new form of corrective tape developed by the same brand for the same purpose although with a different fabric. There is a difference in weaving between the different fabrics of the tape, allowing them to be thicker or thinner. The tapes of the participants in these groups were reapplied twice a week for a total of 4 weeks. The workers continued their home exercise program for 4 weeks. The workers in the control group performed only the home exercise program. Measurements were repeated in the same order at the end of 4 weeks. The tape was removed during the final measurement.

MCT application
The tape application was performed by a physiotherapist with 12 years of experience, who was a certified corrective taping practitioner.
First, an I-shaped tape was measured and cut in a personalized manner for each participant. The anchor of the tape was applied on the anterior aspect of the glenohumeral joint without any tension as the participant sat upright. Subsequently, the participant was asked to retract the scapula bilaterally. While the participant was maintaining this position, the tape was diagonally applied to the inferior border of the scapula with 50-75% tension and the last anchor was applied with no tension. 14,21 The tape was applied to left and right shoulder girdle. The same taping technique was applied to the CT and PT groups using different tape fabrics (Figure 1).

Exercise program
The home exercise program prescribed to all participants consisted of basic postural exercises. These exercises were performed to strengthen the scapular muscles and provide healthy posture. Participants followed the home exercises as indicated in Table 1.

Outcome measures
was measured using a ruler. The measurements were recorded in centimeters. The reliability of this test was demonstrated in a previous study (intraclass correlation coefficient = 0.95). 22,23 In this study, individuals with a measurement result of > 3 cm were considered to have RS. 9 Postural angle assessment (Dr. Goniometer application) Photogrammetry is the most commonly used noninvasive postural measurement because it eliminates possible exposure to harmful radiation during the radiographic method and does not require printing of photographs. Grading is performed by marking the reference bone points and measuring the distance or angle between the specified points. 1 Before the measurement, the reference bone points (the acromion and seventh vertebra) were marked using a pen or a reflective marker to be clearly observed on the photograph.
The camera was set up to take a photograph of the participant from the right lateral side. The participant was subsequently asked to lean forward and backward three times to relax and assume a comfortable standing position. While the participants breathed properly and stood still, a point was marked on the wall directly opposite the participant's eye level to maintain posture. After taking the photo, the cursors on the application screen were adjusted, and the desired angle was recorded (Figure 2). Validity and reliability studies of this smartphone application were conducted, and the intraclass correlation coefficient value was found to be 0.92. 24 Table 1. Exercise program These exercises were provided to both the intervention groups and control group.

Exercise Explanation Intensity 'W' wall slides
At the edge of the wall, when the back is in full contact with the wall, the arms are first opened to the side and bent by the elbows (making a W), dragging upward on the wall without interrupting the arm contact with the wall, and subsequently returning to the initial W position.

sets × 15
Twice a day 4 weeks

Shoulder retraction
Elbows are bent at 90° with arms adjacent to the body. In this position, the shoulder blades are squeezed for 5 s and held close to each other and then loosened. Concurrently, care should be taken not to pull up the shoulders. It is recommended to perform this exercise in front of the mirror if possible.

Backward shoulder rolls
While the arms are adjacent to the trunk, and the elbows are bent, the shoulders are rolled up first, then backward, and downward. The shoulder is required to make a full circle movement. This exercise is continued for 2 min.   14.462, P = 0.001, partial η 2 : 0.287) (P < 0.05). However, in the post hoc analyses, none of the evaluated parameters showed differences among the groups from baseline to 4 weeks (P > 0.05) ( Table 3).

DISCUSSION
To our knowledge, this is the first randomized controlled study to investigate the effects of MCT on muscle stiffness. After 4 weeks of mechanical scapular correction taping application, the results showed that the RS posture significantly decreased in all groups; however, the SA was corrected only in the PT and C groups.   measurements; however, no change in posture was noted. 32 The use of this technique is controversial in the literature. In these studies, posture was generally measured immediately after taping. In contrast, we evaluated the long-term effects in our study. The results were inconsistent with different fabricated tapes. The SA did not change in the CT group; however, it significantly increased in the PT group. Intergroup analyses also showed that no superiority of scapular MCT on the SA over the controls was noted. Since the numerical increase in the SA was mostly in the control group, we cannot conclude that the angular change was due to taping.
We postulate that the exercise program had the necessary effect.
Overactivation and stiffness of the upper trapezius and pectoralis minor muscles associated with weakness of the lower trapezius and rhomboid muscles may cause a relatively protracted shoulder and disrupt normal posture. 33,34 In desk workers, upper trapezius stiffness was shown to increase as the inclination angle of the head changes. 6,35,36 Like the upper trapezius, proper tensionlength relationship and pectoralis minor stiffness are also associated with optimal scapular posture. 9 40 Likewise, in another study, similar exercises were performed while MCT was added to the intervention group. In that study, it was shown that the greatest improvement in craniovertebral angle occurred in the exercise group, and a well-planned exercise program was concluded to help improve posture. 41 In the present study, the exercise program prescribed to all participants included simple postural corrective exercises. The fact that no difference was noted between the groups showed that even a 4-week posture training with simple exercises could achieve the same effect.
Our study had some limitations. First, we performed pre-screening using supine AT distance measurement instead of angular measurement, while similar studies used angular measurements as the inclusion criteria of the participants. We recommend using postural angle data obtained by the photogrammetric method as an inclusion criterion in future studies. Second, a healthy group was not included in the study for comparison. Thus, in future studies, the baseline measurements can also be compared with those of healthy individuals.

CONCLUSION
Scapular mechanical correction using corrective taping in addition to a postural exercise program was not found to be effective for muscle stiffness and posture in workers with RS posture. Different fabrics of tape materials did not result in significant changes.
Therefore, prescribing corrective postural exercises will be more effective for the treatment of muscle stiffness that develops secondary to postural disorders. Based on our study results, we do not recommend the use of scapular MCT with the expectation of corrective and muscle stiffness regulatory effects in the long term.