Introduction

In addition to their main and known role of teaching and qualifying their students, teachers have another essential hard responsibility of educating and developing new generations [1]. Thus, being a teacher can be classified as one of the hardest jobs. In fact, the teaching occupation could be responsible for poor general well-being among school teachers [2]. This fact could be related to the levels of work-related stress and poor physical health accompanying this job [3].

Previous data underlined universally that teachers had a relatively constant high prevalence of mental and physical disorders, notably high blood pressure and musculoskeletal disorders such as low back pain (LBP) [1, 3, 4]. Furthermore, teachers could be more exposed to other health consequences such as coronary heart disease psychiatric disorders, and diabetes [5]. The prevalence of LBP was variable and ranged between 20% in Japan in 2002 [6], 40% in the Philippines in 2020 [7], 50% in Malaysia in 2020 [8], and 90% as reported in an international systematic review in 2011 [9].

Physical activity (PA), considering all the physiological stimulations and secretions that could be generated by regular practice, could have a positive impact on both mental and physical teachers’ health [10]. Several previous studies reported that regular PA could have benefits in reducing teachers’ health problems [10—13].

Previous data reported various frequencies of PA among school teachers. These frequencies were 46.3%, 42.7%, and 11% for low, moderate, and high levels of PA respectively in a previous survey from Brazil [14]. Another study in Poland noted a rate of (32.8%) for low level, (61.2%) for moderate level, and 6% for high level of PA [5]. In Tunisia, more than one in two people from the general population (57.7%) aged 15 and over had insufficient PA in 2016 according to the Tunisian Health Examination survey [15].

To the best of our knowledge, there was a lack of studies that estimated the level of PA among Tunisian school teachers, and there seems to be missing data about the role PA in reducing musculoskeletal health problems among them. In light of this, this study aimed to determine the describe the specificities of PA among schoolteachers and to study its association with low back pain occurrence.

Material and methods

Settings

This was a cross-sectional survey with a representative sample of teachers, conducted in secondary, middle, and primary public schools in Sfax, Tunisia, during the period March 1st to April 30th, 2021.

Sampling procedures

All teachers who were present at the moment of the data collection were eligible for this study. Teachers who did not complete the questionnaire were excluded. The sample of teachers was representative, and it was chosen using a stratified cluster sampling to select teachers from primary, middle, and secondary schools in both rural and urban zones, proportionally to the number of teachers in each school and at each educational level. Using a previous moderate to high level of PA prevalence (57.4%) in a previous similar study in Saudi Arabia [10], a 5% margin of error and a 95% confidence interval, the minimum sample size was 376 teachers.

Data collection and case definition

The data collection tool was an anonymous self-administered questionnaire. Teachers were invited to fill it in their meeting room during their break. The data instrument contained three major parts. The first part included personal, sociodemographic, and clinical characteristics of teachers such as age, gender, marital status, professional grade, lifestyle habits, and history of chronic diseases. A sedentary lifestyle was defined as the absence of regular walking or sports activity, regardless of its intensity, and a sitting position for more than 6 hours per day [16].

PA was classified into three levels. The low PA: when adequate PA was not achieved to be in categories 2 and 3 (below) [14]. Moderate PA was defined as practicing regularly walking briskly, dancing, playing doubles tennis, or raking the yard, slowly, and swimming for a duration of ≥30 minutes per day and ≥3 days per week [17]. High PA was defined as participants having a vigorous PA ≥3 days/week such as a combination of walking and moderate or vigorous exercise accumulating at least ≥30 minutes per day [14].

The second part focused on the working conditions and the professional characteristics, such as working seniority, working area, type of matter taught, and the number of working hours during the current year.

The last part concerned teachers’ physical health such as history of chronic diseases, the measurement of weight, and height, as well as the presence of LBP. Chronic diseases were defined by the World Health Organization (WHO) as being of long duration, generally slow in progression, and not passed from person to person such as heart disease, cancer, and diabetes [18]. LBP intensity was assessed by a Visual Analogue Scale (VAS) graduated from 1 to 10. A severe LBP was defined as VAS ≥7 [19]. Height and weight were measured by a stadiometer graduated in centimeters and a balance, and the Body Mass Index (BMI) was calculated by dividing weight in kilograms by the square of height in meters. Overweight and obesity were defined by a BMI ≥25 kg/m² and BMI ≥30 kg/m², respectively [20].

Participants were subdivided into two groups: group one having moderate to high level of regular PA and a control group reporting none or low level of PA in order to compare physical health problems frequencies, mainly LBP and lifestyle behaviors between the two groups.

Statistical analysis

We used IBM SPSS Statistics v. 26 for data analysis. We used mean ± standard deviation or median and interquartile range (IQR) to describe continuous variables giving to the normality of the variable distribution. Categorical variables were presented as percentages. For the univariate analysis, we used Chi-square test was used to compare two categorical variables in independent samples [Crude Odds Ratio (COR); 95% Confidence Interval (95% CI), p] in order to compare clinical characteristics such as chronic diseases mainly LBP, and lifestyle behaviors among teachers with PA and other who had not. The significance level was of 0.05 (p<0.05).

Results

Main descriptive data about teachers

Among 540 enrolled teachers, 525 participants completed the questionnaire, giving a response rate of 97%. In total, 233 teachers were males (44.4%), and the median age was 48 years (IQR = [41—53] years). There were 424 teachers (80.8%) working in urban localities and 256 (48.8%) subjects working at secondary schools.

Chronic diseases were noted among 123 participants (23.4%) and 41 teachers were current smokers (7.8%). Overall, 147 teachers reported a severe form of LBP, giving a global prevalence of 28% (table 1).

Table 1. Main descriptive data about teachers

Note. VAS — Visual Analogue Scale.

Physical activity levels among teachers

Our results reported that 289 teachers (55.1%) had a regular low level of PA or no PA (control group), 133 teachers (25.3%) had a moderate level and 103 teachers (19.6%) had a high level of PA (group 1) giving a global prevalence of moderate to a high level of PA among teachers of 44.9% (n=236).

Comparison of clinical characteristics and lifestyle behaviors among teachers

Teachers with no or low level of PA had statistically highest rates of severe LBP (Odds Ratio (OR)=1.5; p=0.046), coronary disease (OR=2.89; p=0.001), overweight (OR=1.6; p=0.011) and tobacco consumption (OR=1.9; p=0.042) (table 2).

Table 2. Comparison of clinical characteristics such as chronic diseases mainly low back pain, lifestyle behaviors, and mental health between the two study groups

Note. PA — physical activity; N — Number; % — Percentage; COR — Crude Odds Ratio; 95% CI — 95% Confidence Interval.

Discussion

Results from this original study showed that nearly 45% of South Tunisian teachers practice moderate to high levels of PA. This percentage was relatively lower than other studies from Poland 67% and 54% from Brazil [5, 14]. The differences between frequencies between our results and other countries could be related to the differences in development status between nations, by the differences in definitions used to measure PA in each study and the difference of moments of survey conduction [21]. In our country, there seems to be no data about the prevalence of PA among teachers. Besides, there were some ideas about this frequency among the Tunisian general population. In fact, the WHO reported that only 8.7% of the adult Tunisian population was engaged in moderate or vigorous intensity leisure-time physical activity [22]. This very low prevalence of PA among the general population and teachers could be explained by the awareness of this occupational category, since they are considered as high-level educated people, about the necessity of PA in daily life and its multiple benefits and positive impact on health. By comparing the two groups of teachers in our study, we found that teachers with no or low levels of PA had statistically highest rates of chronic diseases, overweight, cardiovascular disease, severe LBP, and depression. For chronic diseases, overweight, and cardiovascular disease our study results were supported by another previous survey that reported that physical inactivity leads to an increased risk of chronic diseases such as obesity, diabetes, cardiovascular diseases, and renal failure [23]. In fact, it was commonly reported that a healthy lifestyle characterized by regular moderate PA and healthy food was indispensable to guarantee good health regardless of age and profession groups [24]. As for LBP, our survey noted a significant association between no or low level of PA and high rates of LBP, this result was reported by another previous data from Cameron mentioning that Musculoskeletal disorders notably LBP are prevalent among secondary school teachers and statistically associated with a lower level of PA [25]. This association could be scientifically explained by the contribution of PA in blood supplements to muscles and bones, reduction of muscle tension, preservation of joint movement, and pain minimization [25]. We found also that no or low level of PA was statistically associated with depression.

Our study reported that tobacco consumption was statistically more frequent among teachers with no or low PA. In the literature, the results of this association were controversial. A previous study from Saudi Arabia did not report an association between these two facts [10]. Besides, another survey from Turkey concluded that teachers with regular PA had a statistically significantly lower rate of tobacco consumption [26]. This fact could be explained by the socio-cultural differences between nations.

This inventive and valuable study underlines the prevalence of PA among Tunisian teachers and studies the association between regular PA and chronic diseases mainly LBP and lifestyle behaviors. A positive point of our survey was carried out on a representative sample of teachers and with a clear methodology. However, there are some limitations. The cross-sectional design does not necessarily determine cause and effect. Finally, there was still a possibility of biased results since the data collection tool was self-administered and the participants’ responses could be subjective.

Conclusion

This study highlighted a relatively low prevalence of physical activity among South Tunisian school teachers. It showed also a statistical benefit of physical activity among teachers in terms of chronic diseases, low back pain as well as mental health wellbeing. Thus, teachers should be educated and encouraged to do regular moderate or high physical activity. In addition, education and health authorities should plan regularly free days for teachers as well their students to practice physical activity in order to have good health for them and to set an example for their students to adopt a healthy lifestyle since childhood and adolescence.

Funding. The study had no sponsorship.