ABSTRACT
Background/Objectives
Massage therapy has been shown to alleviate stress and improve well‐being, making it a promising intervention for healthcare professionals who often face high levels of job‐related stress. This study investigated the effects of automated massage chair therapy on negative emotional states, musculoskeletal pain, and biochemical markers in healthcare professionals.
Methods
Twenty‐four healthcare professionals with moderate levels of depression, anxiety, and stress were randomly assigned to either an automated massage chair group or a progressive muscle relaxation (PMR) group. Each group received 15‐min sessions, three times per week for 4 weeks, totaling 12 sessions. The depression, anxiety, and stress scale‐21 items (DASS‐21), the visual analog scale (VAS) for pain, and blood biomarkers [brain‐derived neurotrophic factor (BDNF), cortisol, beta‐endorphin, superoxide dismutase 1 (SOD1), endothelial nitric oxide synthase (eNOS), and myeloperoxidase (MPO)] were measured at baseline, after six sessions, and after 12 sessions.
Results
The massage chair group showed significant reductions in depression scores at 6 sessions (Z = −2.043, p = 0.041), and in stress scores at 6 (Z = −2.499, p = 0.012) and 12 sessions (Z = −2.326, p = 0.020). Calf pain scores improved significantly at 12 sessions (right calf: Z = −2.677, p = 0.007; left calf: Z = −2.253, p = 0.024), and lower back pain reduced at both 6 (Z = −2.275, p = 0.023) and 12 sessions (Z = −2.517, p = 0.012). MPO levels were significantly reduced in the massage group post‐intervention (F [1, 22] = 7.956, p = 0.01; t [11] = 2.959, p = 0.013), indicating anti‐inflammatory effects. A significant time effect was also observed for beta‐endorphin (F [1, 22] = 6.632, p = 0.017), with reduced levels after massage (t [11] = 3.321, p = 0.007). No significant changes were found in anxiety, blood pressure, heart rate, BDNF, cortisol, SOD1, or eNOS.
Conclusions
Automated massage chair therapy significantly alleviated depression, stress, and musculoskeletal pain, particularly in the calves and lower back, with modest biochemical changes such as reduced MPO and beta‐endorphin levels. These findings support massage chair use as a convenient, noncontact strategy to enhance psychological and physical well‐being in healthcare professionals.
Keywords: automated massage chair, BDNF, beta‐endorphin, cortisol, emotional distress, endothelial nitric oxide synthase, musculoskeletal pain, myeloperoxidase, superoxide dismutase
1. Introduction
Occupational stress among healthcare professionals has become a significant concern over the past decade, with profound implications for both physical and emotional health. Defined by the National Institute for Occupational Safety and Health [1], occupational stress occurs when job demands exceed the individual's capabilities, resources, or needs. Healthcare professionals, particularly physicians and nurses, are particularly vulnerable to stress due to factors such as inadequate staffing, long working hours, high public expectations, and exposure to infectious diseases and hazardous substances [2, 3]. This stress has been linked to a range of health problems, including cardiovascular disease, psychiatric disorders, psychosomatic symptoms, and, in extreme cases, suicide [4, 5, 6, 7, 8, 9]. Furthermore, the mental health of healthcare professionals remains a major post‐pandemic concern, with continued issues of burnout and stress [10, 11].
In Malaysia, the prevalence of occupational stress varies among healthcare occupations. Yahaya et al. [12] reported a 7.9% prevalence of stress among emergency department medical officers, while Rusli et al. [13] found a 24.6% prevalence among nurses. Lua and Imilia [14] identified radiographers as the most stressed group among support staff, followed by nurses and medical laboratory technologists. Occupational stress in the medical community is associated with numerous health issues, including burnout, sleep disturbances, anxiety, and an overall lack of well‐being [15, 16, 17].
Several interventions have been proposed to alleviate work‐related stress in healthcare workers, including physical activity [18, 19], relaxation technique [20, 21], massage therapy [22, 23, 24], and the use of automated massage chair [23, 25, 26]. Massage therapy, which stimulates sensory nerves in the skin, has been shown to reduce anxiety and depression [22, 24]. However, traditional massages require scheduling with a qualified therapist, and some individuals may not be comfortable with human contact. An alternative, noncontact therapy known as progressive muscle relaxation (PMR), has also demonstrated effectiveness in reducing stress by alternating muscle tension and relaxation, though it requires proper guidance and correct execution to be effective [27].
Automated massage chairs, which provide standardized, noncontact stimulation, offer a promising solution for stress reduction. These devices have been shown to alleviate musculoskeletal tension, improve blood circulation, and reduce stress hormones [26]. Automated back massages are particularly beneficial for individuals who prefer to avoid human touch. As these chairs become more sophisticated and accessible, they offer a convenient, contact‐free alternative to traditional massage therapy. However, empirical evidence on their efficacy remains limited, and the lack of standardization in intensity and modality may lead to inconsistent health outcomes [28].
Chronic occupational stress is known to affect multiple physiological systems, including neuroendocrine, immune, and vascular pathways [29]. To capture these multidimensional effects, selected serum biomarkers were included in this study as objective indicators of stress‐related biological alterations. Specifically, brain‐derived neurotrophic factors (BDNF) play a crucial role in neuronal plasticity, resilience, and mood regulation, and their levels are often diminished in individuals under chronic psychological stress or depressive states [30]. Cortisol, a key glucocorticoid hormone released via activation of the hypothalamic–pituitary–adrenal (HPA) axis, serves as a central marker of both acute and chronic stress responses [31]. Beta‐endorphins, as endogenous opioids, are involved in the modulation of pain and mood, and are typically elevated during stress‐induced analgesia [32]. To assess oxidative stress and vascular function, both of which are disrupted under chronic stress exposure, this study also measured superoxide dismutase 1 (SOD1), a key antioxidant enzyme [33]; endothelial nitric oxide synthase (eNOS), which regulates vascular tone and endothelial health [34]; and myeloperoxidase (MPO), a pro‐oxidant enzyme linked to inflammatory activation [35]. Together, these biomarkers provide a comprehensive physiological profile relevant to the emotional and somatic effects of occupational stress, as well as the potential therapeutic mechanisms of massage‐based interventions.
Given the increasing need for evidence‐based interventions to prevent and manage stress‐related health issues in healthcare professionals, it is essential to explore the effects of automated massage chairs on depression, anxiety, stress, musculoskeletal pain and biochemical markers. Therefore, the aim of this study was to assess the efficacy of automated massage chair therapy on psychological distress (depression, anxiety, and stress), musculoskeletal pain, and selected biochemical markers among healthcare professionals. It is hypothesized that massage chair therapy would lead to greater improvements in psychological distress, musculoskeletal pain, and selected biochemical markers compared to PMR.
2. Materials and Methods
2.1. Participants
The study involved 24 healthcare professionals (11 males, 13 females; mean age of 37.7 ± 8.1 years) recruited from Hospital Universiti Sains Malaysia (HUSM), Kubang Kerian, Kelantan, a tertiary teaching hospital affiliated with Universiti Sains Malaysia. All participants were full‐time staff, including nurses, assistant medical officers, medical laboratory technologists, and radiographers. Recruitment was conducted through internal announcements and emails distributed via the hospital's internal communication system. Individuals who expressed interest were selected based on their highest scores from the self‐reported Depression, Anxiety, and Stress Scale‐21 items (DASS‐21) during the initial screening assessment [36]. Before the study, participants were briefed on the research procedures, and informed written consent was obtained if they agree to participate. The consent forms and study procedures were approved by the Human Research Ethics Committee of Universiti Sains Malaysia (USM/JEPeM/19120958). A familiarization session was conducted during Visit 1 to ensure participants were comfortable with the study setup and protocol. This study was conducted at the Exercise and Sports Science laboratory, School of Health Sciences, Health Campus, Kubang Kerian, Kelantan, Malaysia.
2.2. Study Design
In Visit 2, participants were randomly assigned to either the massage chair or PMR group using a computer‐generated random sequence with a 1:1 allocation ratio. The randomization sequence was stored in a secure, password‐protected database accessible only to an independent staff not involved in enrollment or assessment. The sample size was determined a priori using G*Power software with the following parameters: 80% power, 95% confidence interval, 0.05 alpha level, an effect size (ES) of 0.25, and an estimated 20% dropout rate. Based on these parameters and the previous method used [37], a total of 24 participants were required, with 12 participants per group. The aim was to evaluate the efficacy of massage chair therapy compared to PMR in improving psychological, musculoskeletal, and biochemical health parameters in healthcare professionals. It is hypothesized that massage chair therapy would lead to greater improvements across these outcomes compared to PMR.
Both groups participated in their respective interventions three times per week for 4 weeks, with a total of 12 sessions. Body weight, body height, physio‐psychological measures such as systolic blood pressure (SBP), diastolic blood pressures (DBP), average heart rate (HR), psychological distress, musculoskeletal pain and biochemical markers were assessed at baseline (0‐), 6‐, and 12‐sessions post‐intervention by a trained researcher, with assistance from a medical laboratory technologist from sports science department.
2.3. Massage Chair Intervention
The automated massage chair (Master's Choice, Ogawa Masters Drive AI 2.0) was used according to the manufacturer's recommendation, with a 15‐min duration per session to promote relaxation. Sessions occurred three times per week for 4 weeks. The massage chair was controlled via a Bluetooth‐enabled app (Ogawa Wellness, Ogawa International Holdings Limited). Participants wore normal work clothing, with shoes and personal items removed. The room was set to temperature of 20°C with low lighting ambience to create a relaxing environment.
2.4. Progressive Muscle Relaxation Intervention
Participants practiced PMR while sitting in a semi‐reclining position, with eyes closed and arms and legs placed comfortably on the massage chair's leg and footrest. The massage chair program was not activated during this intervention. Participants assigned to the PMR group underwent 15‐min sessions, three times per week for 4 weeks (totaling 12 sessions). This duration was based on previous studies indicating that a minimum of five sessions is sufficient to reduce somatic and psychological stress symptoms [36, 38]. The PMR protocol was standardized using an audio‐guided recording with consistent narration and instrumental music played at a low volume.
2.5. Psychological Distress Assessments
The Malay version of the Depression, Anxiety, and Stress Scale‐21 items (DASS‐21) scale was used to determine the psychological distress [39]. Each item was rated on a 4‐point scale, from 0 (not at all) to 3 (most of the time). The DASS‐21 is a validated self‐report instrument comprising three subscales (depression, anxiety, and stress) each consisting of 7 items. Participants rated the extent to which they experienced each symptom over the past week on a 4‐point Likert scale ranging from 0 (“Did not apply to me at all”) to 3 (“Applied to me very much or most of the time”). Scores for each subscale are summed and then multiplied by two to match the original 42‐item DASS scale, producing final scores ranging from 0 to 42 for each subscale. Higher scores indicate greater levels of distress. The Malay version of the DASS‐21 has demonstrated good internal consistency, with Cronbach's alpha coefficients reported as 0.84 for depression, 0.74 for anxiety, and 0.79 for stress [40]. It has also shown satisfactory construct validity and is widely used in clinical and nonclinical Malaysian populations.
2.6. Musculoskeletal Complaints
A body chart was used to assess musculoskeletal complaints. Participants marked areas of pain or discomfort experienced in the last 12 months, targeting the area of the neck, back and calves. Pain perception was measured using the VAS, with a range from 0 (no pain) to 10 (worst possible pain) [41, 42].
2.7. Blood Sampling and Biochemical Marker Analysis
Blood samples were collected via venipuncture into 5‐mL tubes, processed immediately, and stored at −20°C until analysis. Serum was obtained through centrifugation (4°C, 10 min, 1500g) and analyzed for biomarkers using enzyme‐linked immunosorbent assay (ELISA) (Raybiotech, Norcross, GA, USA). Serum biomarkers analyzed included BDNF, Superoxide Dismutase 1 (SOD1), Endothelial Nitric Oxide Synthase (eNOS), Beta‐Endorphin, Cortisol, and MPO. To preserve sample integrity, all samples were aliquoted immediately after centrifugation to avoid repeated freeze/thaw cycles. Each aliquot was thawed only once before analysis. Samples were analyzed in duplicate using a microplate reader (Tecan Infinite 200 PRO, Switzerland), with absorbance read at 450 nm. Results with a coefficient of variation (CV) greater than 15% between duplicates were excluded from the analysis.
2.8. Statistical Analysis
All data analyzes were conducted using IBM SPSS Statistics version 27. Descriptive statistics are presented as mean ± standard deviation (SD). Before inferential analysis, normality of all data was assessed using the Shapiro‐Wilk test.
For normally distributed variables (BP, DBP, HR, BDNF, cortisol, beta‐endorphin, SOD1, eNOS, and MPO), General Linear Model (GLM) repeated measures ANOVA was applied to examine within‐subject effects of TIME (baseline, 6 sessions, 12 sessions), between‐subject effects of GROUP (massage chair vs. PMR), and TIME × GROUP interaction effects. Where assumptions of sphericity were violated, Greenhouse‐Geisser correction was applied.
For non‐normally distributed variables [DASS‐21 subscale scores (depression, anxiety, stress) and VAS pain scores for neck, back, and calves], non‐parametric methods were used. The Friedman test was employed to assess differences across timepoints (baseline, 6 sessions, 12 sessions), while the Wilcoxon Signed‐Rank Test was used for pairwise comparisons within groups. Statistical significance was set at a two‐tailed alpha of 0.05.
3. Results
3.1. BP and HR
Resting systolic (SBP) and diastolic blood pressures (DBP) measured at all timepoints were not significantly different between massage chair and PMR [SBP: F(3, 66) = 0.912, p = 0.44; DBP: F(3, 66) = 0.987, p = 0.404]. Participants recruited were normotensive during both massage chair and PMR interventions, showing unchanged responses across pre, 0‐, 6‐ and 12‐ sessions. SBP and DBP were not different across time points for massage chair intervention (no main TIME effect [SBP: F[3, 66] = 1.387, p = 0.255; DBP: F[3, 66] = 1.207, p = 0.314] [See Figure 1A,B]).
Figure 1.

Systolic (A) and diastolic (B) resting blood pressures and average heart rate (C) measured at pre, 0‐, 6‐, 12‐ sessions in participants in both massage chair and progressive muscle relaxation (PMR) interventions. Data in mean ± standard deviation.
Average resting heart rates (HR) were not significantly different between massage chair and PMR interventions across 0‐, 6‐, and 12‐sessions (F[2, 44] = 1.388, p = 0.26) (See Figure 2). Resting HR were normal in all participants during both intervention sessions. Within‐subject analysis showed massage chair intervention showed a main TIME effect (F[2, 44] = 3.459, p = 0.04)at 6‐ and 12‐sessions. (See Figure 1C).
Figure 2.

Depression (A), anxiety (B) and stress (C) scores measured at 0‐, 6‐, 12‐ sessions in participants for both massage chair and progressive muscle relaxation (PMR) interventions. *Significantly different from 0‐session for massage chair intervention.
3.2. DASS‐21
3.2.1. Depression, Anxiety and Stress Scores
There was significant difference in depression scores 2(2, N = 24) = 16.037, p = 0.0001] between massage chair and PMR interventions. For massage intervention, depression scores were lower at 6‐sessions compared to 0‐session (Z = −2.043, p = 0.041) (see Figure 2A).
Anxiety scores were not significantly different 2(2, N = 24) = 4.083, p = 0.130] between massage chair and PMR interventions. For massage intervention, anxiety scores were not significantly different at 6‐ (Z = −0.997, p = 0.319) and 12‐session (Z = −1.476, p = 0.140) compared to 0‐session (see Figure 2B).
Stress scores were not significantly different 2(2, N = 24) = 12.487, p = 0.002] between massage chair and PMR interventions. For massage intervention, stress scores were significantly different at 6‐ (Z = −2.499, p= 0.012) and 12‐sessions (Z = −2.326, p = 0.020) compared to 0‐session (see Figure 2C).
3.3. Musculoskeletal Pain Scores
3.3.1. Neck Pain
There was no significant difference in neck pain score 2(2, N = 24) = 14.852, p = 0.001] between massage chair and PMR interventions. Wilcoxon Signed Ranks Test showed that neck pain was significantly lower in massage chair intervention at 6‐ (Z = −2.222, p = 0.026) and 12‐sessions (Z = −2.958, p= 0.003) compared to 0‐session, respectively (see Figure 3).
Figure 3.

Neck pain scores measured at 0‐, 6‐, 12‐ sessions in participants for massage chair and progressive muscle relaxation (PMR) intervention group. *Significantly different from 0‐session for massage chair intervention.
3.3.2. Upper and Lower Back Pain
There was no significant difference in upper back pain score 2(2, N = 24) = 5.429, p = 0.066] between massage chair and PMR interventions. However, lower back pain score was significantly different [ 2(2, N = 24) = 10.586, p = 0.005] between massage chair and PMR interventions. Wilcoxon Signed Ranks Test showed that lower body pain score was lower at 6‐ (Z = −2.275, p = 0.023) and 12‐sessions (Z = −2.517, p = 0.012) compared to 0‐week for massage chair intervention (See Figure 4).
Figure 4.

Upper (A) and lower (B) back pain scores measured at 0‐, 6‐, 12‐ sessions in participants in both massage chair and progressive muscle relaxation (PMR) interventions. *Significantly different from 0‐session for massage chair intervention.
3.3.3. Right and Left Calf Pain
There was significant difference in right calf pain score 2(2, N = 24) = 10.571, p = 0.005] between massage chair and PMR interventions. For massage intervention, right calf pain scores were lower at 12‐sessions compared to 0‐session (Z = −2.677, p = 0.007) and at 12‐sessions compared to 6‐sessions (Z = −1.973, p = 0.049) (see Figure 5A).
Figure 5.

Right (A) and left (B) calves scores measured at 0‐, 6‐, 12‐ sessions in participants for both massage chair and progressive muscle relaxation (PMR) interventions. *Significantly different from 0‐session for massage chair intervention; + Significantly different from 6‐session for massage chair intervention.
However, left calf score was not significantly different [ 2(2, N = 24) = 5.059, p = 0.08] between massage chair and PMR interventions. However, Wilcoxon Signed Ranks Test showed that left calf pain score was lower at 12‐sessions (Z = −2.253, p = 0.024) compared to 0‐session for massage chair intervention (see Figure 5B).
3.4. Blood Biomarkers
3.4.1. BDNF, Cortisol, and Beta‐Endorphin
There was no significant difference in BDNF (F[1, 22] = 0.008, p = 0.928) between massage chair and PMR interventions. The BDNF concentrations were not significantly different across time points for both massage chair and PMR interventions (Main TIME effect: F[1, 22] = 1.764, p = 0.198) (See Figure 6A). Similarly, cortisol concentrations were not significantly different (F[1, 20] = 0.188, p = 0.669] between massage chair and PMR interventions. The cortisol concentrations were not significantly different across time points for both massage chair and PMR interventions (Main TIME effect: F[1, 20] = 1.556, p = 0.072) (See Figure 6B). There was no significant difference in beta‐endorphins (F[1, 22] = 1.377, p = 0.253) between massage chair and PMR interventions. However, there was a main TIME effect (F[1, 22] = 6.632, p = 0.017), with the beta‐endorphins concentrations significantly reduced at post massage chair intervention (t[11] = 3.321, p = 0.007] (See Figure 6C).
Figure 6.

Concentration of serum brain‐derived neurotrophic factor (BDNF) (A), cortisol (B) and beta‐endorphin (C) measured at 0‐, 6, 12‐ sessions in participants for both massage chair and progressive muscle relaxation (PMR) interventions. Data in mean ± SD. *Significantly different from pre for massage chair intervention.
3.4.2. SOD1, eNOS, and MPO
There was no significant difference in SOD1 (F[1, 22] = 0.942, p = 0.342) between massage chair and PMR interventions. The SOD1 concentrations were not significantly different across time points for both massage chair and PMR interventions (Main TIME effect: F[1, 22] = 1.018, p = 0.324) (See Figure 7A).
Figure 7.

Serum concentrations of superoxide dismutase 1 (SOD1) (A), endothelial nitric oxide synthase (eNOS) (B) and myeloperoxidase (MPO) (C) measured at 0‐, 6‐, 12‐ sessions in participants for both massage chair and progressive muscle relaxation (PMR) interventions. Data in mean ± standard deviation. *Significantly different between massage chair and PMR interventions.
Similarly, there was no significant difference in eNOS (F[1, 22] = 0.550, p = 0.466) between massage chair and PMR interventions. The eNOS concentrations were not significantly different at post intervention for both massage chair and PMR (Main TIME effect: F[1, 22] = 1.108, p = 0.304) (See Figure 7B).
There was a significant difference in MPO concentrations (F[1, 22] = 7.956, p = 0.01) between massage chair and PMR interventions. There was a main TIME effect (F[1, 22] = 4.548, p = 0.044], with MPO concentrations significantly reduced at post massage chair intervention (t[11] = 2.959, p= 0.013) (See Figure 7C).
4. Discussion
The findings from this study offer important insights into the effectiveness of automated massage chair therapy, particularly in comparison to PMR for managing musculoskeletal pain, psychological distress, and inflammatory biochemical markers. The massage chair intervention was found to significantly reduce musculoskeletal pain in the neck, lower back, and calf regions, demonstrating its potential as an effective nonpharmacological treatment for pain management. These results are aligned with recent research indicating that massage chair therapy can provide substantial relief for musculoskeletal pain [43, 44]. Our study found that massage chair therapy significantly alleviated pain in the neck, lower back, and calves after 6 and 12 sessions. Massage devices, including automated systems, have been shown to have similar efficacy to manual massage, with advantages such as convenience and accessibility [44]. The improvement in lower body pain, particularly in the calves, highlights the potential of massage chair therapy for addressing localized discomfort. Interestingly, no significant differences were found in upper back pain reduction between massage chair and PMR interventions, suggesting that the therapeutic effects of automated massage may be more effective in certain anatomical regions. The efficacy of massage may vary by muscle group, with certain areas benefiting more from massage due to work‐related muscle discomfort. One such example of a healthcare job is the cardiac sonographer, who showed improved musculoskeletal conditions following massage chair therapy [45].
The massage chair intervention was also effective in reducing both stress and depression scores, reflecting its impact on psychological well‐being. These findings corroborate recent studies showing that massage therapy can lead to significant reductions in stress and depressive symptoms by promoting relaxation and modulating the autonomic nervous system [46, 47]. Moreover, the observed improvement in stress scores after both 6 and 12 sessions emphasizes the potential of massage chair therapy in stress and fatigue management [48], especially in the healthcare settings where managing stress is critical. Frequent and long‐term use of a massage chair can significantly reduce stress in healthcare professionals experiencing high levels of work‐related stress [25]. In Malaysia, the healthcare industries have been reported to have high prevalence of occupational stress [12, 14, 49, 50].
The anxiety scores did not show significant improvement, which may suggest that while massage can alleviate stress and depression levels, its effects on anxiety may be less pronounced. Massage's ability to reduce anxiety may depend on factors such as the intensity of the massage and the individual's baseline anxiety levels [51, 52]. For example, Swedish massage has been found to reduce anxiety of generalized anxiety disorder compared to light massage [53] while effleurage type of massage reduces anxiety in multiple sclerosis patients who experienced much more pronounced anxiety [54]. Thus, while massage therapy shows promise in addressing stress and depression, further exploration is needed to understand its effects on anxiety more thoroughly.
In terms of physiological parameters, the massage chair intervention did not produce significant changes in BP or HR. These results are consistent with studies suggesting that massage therapy has minimal effects on cardiovascular parameters in normotensive individuals [55]. The lack of significant change in these measures supports the safety aspects of massage chair therapy, indicating that it does not negatively affect cardiovascular function in healthy individuals [56].
Our results also indicated a significant reduction in MPO levels following the massage chair intervention, which points to potential anti‐inflammatory effects. MPO is a marker of neutrophil activation, known as inflammatory and oxidative markers of stress [57]. Our findings on MPO are in line with studies suggesting that massage therapy can modulate immune function and reduce inflammation, possibly through mechanisms such as improved circulation and reduced muscle tension [58, 59]. In contrast, no significant changes were observed in other biomarkers, such as BDNF, SOD1, eNOS, or cortisol levels in the current study. BDNF is an important neuroprotective growth factor, and its secretion is said to be dependent on the event of damage to the neuron cells [60]. The SOD1 and eNOS are both secreted in oxidative‐stressed neuro and endothelial cells respectively. Thus, it is believed that the unchanged levels in these biomarkers showed massage chair sessions may be utilized safely without contraindications up to 12 sessions (3 x weekly for 20 min). Cortisol, a measure of stress hormone, is more extensively studied in stress studies and is shown to be reduced in another study on a large cohort of 82 hospital bedside nurses, a 10‐min massage chair session reduced the perception of stress compared to a regular “coffee break” session of similar duration [61]. The reduction in cortisol levels in individuals receiving massage chair therapy may be attributed to the specific job responsibilities of these healthcare professionals [62]. Therefore, it is plausible to suggest that the impact of massage on reducing stress levels in healthcare professionals remains inconclusive [63]. Taken together, the lack of significant response in these blood biomarkers may indicate that the therapeutic effects of massage chair therapy in the current study may be more localized or that the systemic effects are not more pronounced than in a much more demanding job environment (i.e. intensive care nurses) [24].
The decrease in beta‐endorphins seen after the intervention implies that, like manual massage and other therapeutic touch, the analgesic effects of massage chair therapy may be mediated by the activation of endogenous opioid systems [64, 65]. Our current study found a decrease in beta‐endorphin; however, this finding does not negate the pain‐relieving benefits of massage. The effect of pain is not always directly correlated with beta‐endorphin levels [66]. Nevertheless, we believe that with long‐term usage of a massage chair, overall well‐being of the healthcare professionals can be maintained. In Engen et al.'s study [23], 38 nurses (78.95%) who received 15‐min weekly massage chair therapy for 10 weeks during work hours reported improved job satisfaction, and 23 (60.53%) expressed willingness to pay USD $10–25 for a 15‐min massage at work. Thus, long‐term use of massage chair therapy may reduce job dissatisfaction, potentially increasing job retention among healthcare professionals.
While the current study provides promising results, several limitations should be considered. Our participants' biomarker values at both baseline and post‐intervention were largely within the expected physiological reference ranges. participants' biomarker values at both baseline and post‐intervention were largely within accepted physiological reference ranges. Serum BDNF levels ranged within the expected 15–30 ng/mL range reported in healthy adults [67, 68]. Likewise, morning cortisol concentrations fell within the typical reference interval of 140–690 ng/mL [69]. The absence of biomarker dysregulation at baseline may have constrained the potential for significant pre–post changes in this relatively healthy population. Based on the results of the present study, although the massage chair group reported slightly higher baseline pain scores in the upper back, lower back, and calves compared to the PMR group, these differences were not statistically significant. As group allocation was randomized and no systematic recruitment bias was identified, the observed baseline variations are likely attributable to random variation inherent in the group assignment process, particularly given the modest sample size. The present study investigates a diverse group of healthcare professionals, who have different job‐related tasks which may produce different localized symptoms (i.e. musculoskeletal pain). Future studies are needed to confirm these results and assess by job scope and work duration to understand the broader applicability of massage chair therapy in certain healthcare jobs. Additionally, a longer follow‐up period would help clarify the long‐term benefits of the massage intervention.
Future research should also explore the underlying mechanisms of action, particularly the neurobiological pathways involved in the therapeutic effects of massage, to gain a deeper understanding of its impact on inflammation, pain, and psychological health.
5. Conclusions
The massage chair intervention demonstrated several beneficial effects, particularly in reducing musculoskeletal pain and stress. While it did not significantly affect blood pressure, heart rate, or anxiety levels, it significantly alleviated pain in the neck, lower back, and calves, with reductions observed after 6‐ and 12‐session interventions. Additionally, depression and stress scores improved after the massage chair sessions. Notably, the intervention also reduced MPO concentrations, indicating a potential anti‐inflammatory effect. However, no significant changes were observed in biomarkers such as BDNF, SOD1, eNOS, and cortisol. These findings suggest that massage chair therapy may be a promising nonpharmacological approach for managing musculoskeletal pain and stress in healthcare professionals, with a favorable relaxation profile state similar to PMR intervention. Therefore, healthcare professionals may benefit from using automated massage chair therapy should it be available in the healthcare settings. Further research is needed to fully elucidate its mechanisms and to explore its long‐term benefits.
Author Contributions
Marilyn Li Yin Ong: conceptualization, methodology, formal analysis, data curation, visualization, writing — original draft, writing — review and editing. Adam Abdul Malik: conceptualization, methodology, investigation, writing — review and editing. Norhasmah Mohd Zain: conceptualization, methodology, investigation, writing — review and editing. Nurulilyana Sansuddin: conceptualization, methodology, investigation, writing — review and editing. Norazliah Hj Samsudin: conceptualization, methodology, investigation, writing — review and editing. Rosminah Mohamed: conceptualization, methodology, investigation, writing — review and editing. Idris Long: conceptualization, methodology, investigation, writing — review and editing. Nor Haslina Mohd: conceptualization, methodology, investigation, writing — review and editing. Nurul Asma Abdullah: conceptualization, methodology, investigation, resources, writing — review and editing. Hairul Anuar Hashim: conceptualization, methodology, formal analysis, supervision, funding acquisition, visualization, project administration, writing — review and editing, data curation, resources.
Ethics Statement
The study was conducted in accordance with the Declaration of Helsinki and approved by Human Research Ethics Committee of Universiti Sains Malaysia (protocol code USM/JEPeM/19120958 and date of approval May 4th, 2020).
Consent
Written informed consent was obtained from all participants before agreeing to be involved in this study (printed and signed). Written informed consent has been obtained from the participants to publish this article.
Conflicts of Interest
The funder had no role in the design of the study; in the collection, analyzes, or interpretation of data; in the writing of the article; or in the decision to publish the results. There is no other conflict of interest to declare.
Transparency Statement
The lead author Hairul Anuar Hashim affirms that this article is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.
Acknowledgments
The authors would like to thank Madam Norlida Azalan@ZED and Madam Nur Fadhilah Ain Md Adanan for their assistance in the biochemical analysis. All participants were thanked for volunteering in the research project. This study and APC were funded by Healthy World Lifestyle Sdn. Bhd. (OGAWA), grant number OGW‐USM‐AO2663‐04.
Data Availability Statement
All data related to this study has been included in the results section of this article. The data that support the findings of this study are available from the corresponding author upon reasonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
All data related to this study has been included in the results section of this article. The data that support the findings of this study are available from the corresponding author upon reasonable request.
