<![CDATA[The production of cigarettes involves manual labor, and some workers experience issues such as pain and cramping in the back of the thigh. These are symptoms of hamstring muscle shortening. Shortened hamstring muscles are often considered a primary risk factor for muscle injury, as well as a problem related to muscle health or the musculoskeletal system. The aim of this study is to determine the relationship between work posture, length of service, and individual characteristics and hamstring muscle flexibility. A cross-sectional study was conducted among 55 cigarette factory workers in Kudus, Indonesia, selected by proportional random sampling. Data on age, exercise habits, and years of experience were collected using questionnaires, while work position, BMI, and hamstring flexibility were assessed through observation, anthropometric measurements, and the V-Sit and Reach Test. Bivariate analysis used the Chi-square test at a 5% significance level. The mean age of the respondents was 46.51 years, with an average exercise frequency of 1.31 times per week. A total of 56.4% of respondents fell into the normal category, and 61.8% had a tenure of less than 4 years. Chi-square analysis showed the following results: age (p=0.020), BMI (p=0.205), exercise habits (p=0.000), work posture (p=0.273), and tenure (p=0.386). Conclusion: Age and exercise habits are risk factors associated with hamstring muscle flexibility among cigarette workers in Kota Kudus District, Kudus Regency. Age and exercise habits were significantly associated with hamstring flexibility. Workplace programs should promote regular physical activity, active breaks, mobility exercises, and stretching, particularly for older workers]]>
