Studies indicate that adolescents spend approximately 1.5 hours daily on smartphones, exacerbating FHP, rounded shoulders, and abnormal spinal curvature [6, 7, 8]. These issues manifest as neck pain, upper back discomfort, and tenderness upon palpation due to repetitive strain on cervical musculature [9]. Given the long-term implications for spinal health, targeted rehabilitation interventions, such as corrective exercise programs, are critical [2, 10].
This study evaluates the impact of an 8-week corrective exercise protocol on neck muscle length, strength, and endurance in female students aged 12–14 years diagnosed with Text Neck Syndrome.

Methods

This randomized controlled trial employed a pretest-posttest design with a control group. The study population comprised female students aged 12–14 years in Hamedan city, Iran, diagnosed with Text Neck Syndrome. From 150 volunteers, 86 met the inclusion criteria, and after 16 withdrawals, 70 participants were randomized into an intervention group (n=35) or a control group (n=35). Due to dropouts, 32 participants remained in each group.
Inclusion Criteria: Participants were required to be aged 12–14 years, send/receive at least 25 text messages daily, engage in at least one hour of mobile gaming or browsing, and use smartphones for a minimum of three hours daily [15].
Exclusion Criteria: Participants were excluded if they missed more than two exercise sessions, engaged in external physical activities, or withdrew consent.
The intervention group participated in an 8-week corrective exercise program, conducted three times weekly for 60-minute sessions. The program included posterior and lateral neck muscle stretches, wall-supported shoulder stretches, pectoralis minor stretching, and progressive isometric resistance exercises (15–30 seconds per set) [10]. Each session began with a 10-minute dynamic warm-up and concluded with a 10-minute cool-down to enhance recovery. The control group received no intervention.
Validated tools were used to measure pectoralis minor length (standard ruler), neck flexor and extensor strength (North Coast handheld dynamometer), and muscle endurance (standardized cervical flexion and extension tests) [16, 17]. A blinded assessor performed all measurements. Data analysis was conducted using SPSS version 26, employing repeated-measures ANOVA and paired t-tests, with a significance level of 0.05.

Results

The corrective exercise program yielded significant improvements in all measured outcomes. In the intervention group, pectoralis minor length increased bilaterally (p<0.001), with no significant changes in the control group (p>0.05). Neck flexor and extensor strength improved by 30.38% and 34.20%, respectively, in the intervention group (p<0.001), while the control group showed a 10.75% reduction in flexor strength (p=0.048). Neck flexor and extensor endurance increased by 89.47% and 92.48%, respectively, in the intervention group (p<0.001), whereas the control group experienced a 17.87% decrease in extensor endurance (p=0.022).
Between-group analyses confirmed significant time-by-group interactions for all variables (p<0.001). Additionally, the intervention group reported reduced neck pain and improved FHP, underscoring the clinical benefits of the rehabilitation protocol.

Discussion and Conclusion

These findings align with sports rehabilitation research emphasizing corrective exercises for postural correction. For instance, Jaroenrungsup et al. demonstrated that targeted stretching improves pectoralis minor length, reducing muscle tightness—consistent with the current study’s results [11]. Stretching induces viscoelastic changes, enhancing muscle flexibility and alleviating strain from FHP [22].
Isometric exercises strengthened deep cervical flexors and extensors, stabilizing the cervical spine and correcting the disrupted length-tension relationship caused by Text Neck Syndrome [27]. The "chin-tuck" exercise, a key component of rehabilitation, significantly enhanced deep cervical flexor strength, reducing strain on superficial muscles and alleviating pain [27].
Supporting studies, such as Sarraf et al. and Roshani et al., confirm that corrective exercises improve FHP, rounded shoulders, and associated symptoms by addressing muscle imbalances [10, 13]. The control group’s decline in endurance highlights the detrimental effects of unchecked smartphone use, emphasizing the need for preventive rehabilitation in adolescents [26].
Strengths of the Study: The study’s randomized controlled design, blinded assessments, and standardized measurement tools ensure robust results.
Limitations: The sample was restricted to female students aged 12–14 in Hamedan, limiting generalizability. The absence of long-term follow-up or advanced imaging (e.g., MRI) to assess structural changes and uncontrolled factors (e.g., sitting habits, precise smartphone usage) may have influenced outcomes.
In conclusion, the 8-week corrective exercise program significantly improved pectoralis minor length, neck muscle strength, and endurance while reducing pain and correcting FHP in female students with Text Neck Syndrome. Integrating such rehabilitation protocols into school-based programs could mitigate the rising prevalence of this condition. Future research should explore long-term outcomes, diverse populations, and advanced imaging to further validate these findings.

Ethical Considerations

This study was approved by the Research Ethics Committee of Bu-Ali Sina University under the code IR.BASU.REC.1402.021 and registered in the Iranian Registry of Clinical Trials with the code IRCT20230711058742N1.

Funding

There is no funding support.

Authors’ Contribution

In this study, the first and third authors were responsible for data collection and initial manuscript drafting, while the second author led the conceptualization, data analysis, and manuscript editing. All authors contributed equally to the conceptualization and writing of the article. Each author reviewed and approved the final manuscript, agreeing on all aspects of the work.

Conflict of Interest

Authors declared no conflict of interest.

Acknowledgments

We sincerely thank all the students who participated as subjects in this study and supported its implementation.

Authors’ Contribution

Authors contributed equally to the conceptualization and writing of the article. All of the authors approved the content of the manuscript and agreed on all aspects of the work.