DOI 10.1515/ijamh-2013-0319 Int J Adolesc Med Health 2014; aop
Whye Lian Cheah*, Hazmi Helmy and Ching Thon Chang
Factors associated with physical inactivity among female and male rural adolescents in Borneo – a cross-sectional study Abstract: Rural communities have shown marked increase in metabolic syndrome among young people, with physical inactivity as one of the main contributing factors. This study aimed to determine factors associated with physical inactivity among male and female rural adolescents in a sample of schools in Malaysia. A crosssectional study was conducted among 145 students aged 13–15 years. Data on socio-demographic, health-related, and psychosocial factors (perceived barriers, self-efficacy, social influences) were collected using a self-administered questionnaire. Anthropometric measurement was taken to generate body mass index (BMI)-for-age, while physical activity (PA) level was assessed using pedometers. The mean steps per day was 6251.37 (SD = 3085.31) with males reported as being more active. About 27% of the respondents were either overweight or obese, with more females in this group. There was no significant difference in steps among males and females (p = 0.212), and nutritional status (BMI-for-age) (p = 0.439). Females consistently scored higher in most items under perceived barriers, but had significantly lower scores in self-efficacy’s items. Males were more influenced by peers in terms of PA (p < 0.001) and were more satisfied with their body parts (p = 0.047). A significantly higher body size discrepancy score was found among females (p = 0.034, CI –0.639, –0.026). PA level was low and almost one-third of the respondents were overweight and obese. Female students faced more barriers and had lower self-efficacy with regards PA. Based on the findings, it is recommended that interventions focus on reducing barriers while increasing support for PA. This is particularly important in improving the health status of the youth, especially among the females. Keywords: perceived self-efficacy.
barriers;
physical
activity;
*Corresponding author: Dr. Whye Lian Cheah, PhD, Senior Lecturer, Faculty of Medicine and Health Sciences, Department of Community Medicine and Public Health, Universiti Malaysia Sarawak, Lot 77,
Section 22 KTLD, Jalan Tun Ahmad Zaidi Adruce, 93150 Kuching, Sarawak, Malaysia, Phone: +6082 226222, E-mail:
[email protected] Hazmi Helmy: Faculty of Medicine and Health Sciences, Department of Community Medicine and Public Health, Universiti Malaysia Sarawak, Sarawak, Malaysia Ching Thon Chang: Faculty of Medicine and Health Sciences, Department of Nursing, Universiti Malaysia Sarawak, Sarawak, Malaysia
Introduction A population study done in Malaysia in 2004 reported that the prevalence of metabolic syndrome among younger age groups was higher among Indigenous Sarawakians compared with other ethnic groups (1). Individuals with metabolic syndrome had higher risk of developing cardiovascular disease (2). With the increasing socio-economic affluences, this phenomenon affects not only the adults but also adolescents. One of the contributing factors that increase metabolic syndrome is lack of physical activity (PA). There are many health benefits of physical activities in adolescents. Adolescents need it to help build healthy bones and muscles (3). PA also has protective effects for adolescents against obesity and other chronic diseases such as diabetes, cardiovascular disease, and colon cancer during adulthood as well as promotes psychological wellbeing (3). Other studies found that PA helped improve students’ academic performance (4). Despite its benefits, many studies showed a marked decline in PA during adolescence (5, 6). A recent study carried out among adolescents in Kuantan, Malaysia indicated that only 3% of the adolescents were at the high PA level, while the rest of the respondents were inactive (7). Findings from the Malaysia National Health and Morbidity Survey III revealed that 43.7% of the Malaysian adults were physically inactive (8). There are many factors associated with physical inactivity in adolescents. Biological, socio-demographic, health-related factors and psycho-social factors were
2 Cheah et al.: Physical inactivity among rural adolescents in Borneo
found to be associated with physical inactivity (9, 10). Sociodemographic factors, such as gender and age, influence different levels of PA, and older or female adolescents were found to be more inactive compared with younger or male ones (11). Psychosocial factors, such as behaviors, comprise one of the considerable potential important determinants of PA level, particularly during adolescence – a period marked by intense physical, psychosocial, and cognitive developmental changes (12). In Malaysia, a study carried out among adolescents in secondary schools found that the predictors for adolescents to engage in PA included PA self-efficacy, sex, and peer influence (7). Though the same study also indicated that males were more physically active, further analysis did not explore the difference in psychosocial factors between males and females (7). In addition, PA level was measured in the form of self-reported questionnaire, which excluded physical activities outside the school. The current study is proposed to ascertain the factors associated with physical inactivity among male and female adolescents in Sarawak, where the ethnic composition differs from that in Peninsular Malaysia. With the use of a pedometer, a more accurate level of PA can be captured.
Materials and methods Study population For this cross-sectional study, two rural secondary schools located in Bau district were randomly selected, wherein the majority of students were Indigenous Sarawakians (Bidayuh). Both schools had a co-educational student composition. All form 2 and form 4 students in the two schools who were intellectually capable, physically fit without any illnesses (e.g., asthma, heart condition, etc.) were invited to participate. Form 3 and form 5 students were excluded because of their involvement in the government public examinations (Penilaian Menengah Rendah and Sijil Pelajaran Malaysia). Permission was granted by the Ministry of Education and school principals before entering the schools. Written consent was also obtained from the parents of the respondents. Ethical approval was obtained from the Medical Research Ethical Committee, Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak. Using PS software 3.0.43, based on the proportion rate (35.5% for low PA level, 61.5% moderate PA level) reported in Dan et al. (7), study power of 0.8 and type 1 error probability of 0.05, a total of 130 sample (including attrition rate of 10%) was needed for this study.
weight and height; (c) pedometer reading based on 1 week reading that included both the weekdays and weekends; (d) perceived barriers to PA, 21 items; (e) PA self-efficacy, 17 items; (f) social influences for PA, 8 items; (g) beliefs for PA outcomes, 16 items; (h) perception of body size, 3 items; and (i) satisfaction with body parts, 10 items. The Malay version of the questionnaire was obtained with permission from Dan et al. (7), with an internal consistency (Cronbach’s α) of 0.67–0.93.
Anthropometric measurements Measurement of body height and weight were done using SECA portable weighing scale and body meter (Birmingham, UK). The respondents were asked to remove their shoes before their weight was taken. For height measurement, respondents stood upright on a flat surface; they were barefoot and the back of their heels and occiput were against the body meter. Body mass index (BMI) was calculated using formula of weight by height squared (kg/m2). The calculated BMI was plotted onto BMI-for-age percentile charts for different genders and classified into thin, normal, overweight, and obese based on WHO reference 2007 (13).
Assessment of PA A pedometer is one of the most preferred instrumentation in measuring PA because of its affordability and ease of interpretation (14). For this study, Yamax Digi-Walker CW-70 was used (Tokyo, Japan). All respondents were asked to wear the pedometer to record the amount of steps they accumulated over a 1-week period. The pedometer was clipped at the waist through a rubber belt specially tailored for this study. Each pedometer was set by the researchers before it was attached to the respondent. Respondents were briefed on how to care for the pedometer while using it.
Perceived barriers to PA The perceived barriers to PA is a 21 items instrument adopted from Allison et al. (11). Items are scored on a 5-point scale ranging from “not at all” [1] to “a great deal” [5].
PA self-efficacy The instrument consists of 17-item questions that assessed perceived self-efficacy or confidence in respondents in carrying out any PA. The scale was adapted from Saunders et al. (15) and used a 5-point scale ranging from 1 – “not at all confident” to 5 – “extremely confident”. Higher scores indicate higher self-efficacy for PA.
Data collection
Social influences for PA
Data were collected using a self-administered questionnaire. The questionnaire consisted of the following: (a) sociodemographic information (sex, age, race, religion, parent’s occupation); (b)
This scale was adapted from Saunder et al. (15). It measures peer and family influences on a person’s PA, based on a 5-point scale ranging from 1 – “not at all” to 5 – “a great deal”.
Cheah et al.: Physical inactivity among rural adolescents in Borneo 3
Beliefs in PA outcomes Based on a total of 16 items, this scale was adapted from Saunder et al. (15). Using a 5-point scale ranging from 1 – “strongly disagree” to 5 – “strongly agree”, this instrument assesses beliefs in PA outcome. Higher scores indicate stronger positive belief in PA outcome.
Body image This component consists of two sub-sections, namely, perception of body size and body parts satisfaction. Under perception of body size, respondents were asked to choose figures based on the “Contour Drawing Rating Scale” (16), to represent their own perception towards their current body size, ideal body size, and healthiest body size. Based on the difference between perceived current body size and perceived ideal body size, a score is then generated. For perception of body parts, respondents were asked to perceive their body parts and indicate scores a 5-points scale ranging from 1 – “strongly dissatisfied” to 5 – “strongly satisfied”. This instrument was adopted from Dan et al. (7).
Statistical analysis Data were entered and analyzed using SPSS for Windows version 19.0. Data were cleaned for outliers and checked for normality using Kolmogorov-Smirnov. Majority of Kolmogorov-Smirnov normality tests showed p > 0.05, indicating normal distribution of data. In addition to the descriptive information, independent t-test was employed to determine the association between psychosocial factors and sex based on a p < 0.5 (2-sided).
Results A total of 145 respondents participated in the study; of these, 66.2% were female and 66.9% were Bidayuh.
Based on the BMI classification, there were 11.7% obese and 15.2% overweight respondents. There was a higher proportion of overweight female respondents compared with the males. However, under the category of obese, both male and female respondents had almost similar proportion, with the male group being a bit higher. Mean step per day was 6251.37 (SD = 3085.31). Between males and females, males recorded higher mean step per day (6699.67, SD = 3605.46) compared with females (6022.55, SD = 2775.66) (Table 1). The overall mean score of perceived barriers was relatively low with only one item of 3.0. Perceived barriers related to too much homework was reported to be the highest factor that caused physical inactivity. Items such as “weather is too bad”, “do not have anyone to do PA with and lack of convenience place to go”, “friends do not like to do PA”, “lack of time”, “chosen last for teams”, “no one at the skill level to do PA with”, “don’t want people to see the body when doing PA”, “lack of skills”, and “lack of knowledge on how to do PA” were the perceived barrier components that received mean scores of 2.0 or greater. Further analysis on the factor structure of these components indicated they were mainly from external factors (Table 2). In comparing males and females, majority of the females scored higher in all perceived barrier components except in the following items: “too overweight to do PA”, “have too much homework”, and “weather is too bad”. However, only four items showed significant differences between males and females, namely, “lack of interest in PA” (p = 0.011), “lack of skills” (p = 0.016), “lack of knowledge on how to do PA” (p = 0.008), and “weather is too bad” (p = 0.048).
Table 1 Characteristics of the subjects (n = 145). Characteristics
n (%)
Mean (+SD)
Sex Male Female Ethnicity Malay Chinese Bidayuh Others (including Iban) School time Morning session Afternoon session
49 (33.8%) 96 (66.2%) 4 (2.8%) 34 (23.4%) 97 (66.9%) 10 (6.9) 64 (44.1%) 81 (55.9%)
Classification of BMI Obese Overweight Normal Thinness and below Physical activity level (step per day)
All 17 (11.7%) 22 (15.2%) 101 (69.7%) 5 (0.7%)
6251.37 (3085.31)
Male (n = 49) 9 (18.0%) 7 (14.3%) 31 (63.3%) 2 (4.1%) 6699.67 (3605.46)
Female (n = 96) 8 (8.3%) 15 (15.6%) 70 (72.9%) 3 (3.1%) 6022.55 (2775.66)
4 Cheah et al.: Physical inactivity among rural adolescents in Borneo Table 2 Mean scores of perceived barriers and self-efficacy by gender (n = 145).
All (n = 145)
Mean
SD Mean
Perceived barrier-internal Self-conscious about my looks when I do PA 1.85 0.915 Self-conscious of my body when I do PA 1.87 1.043 Don’t want people to see my body when I do PA 2.17 1.149 Lack of interest in PA 1.88 1.033 Lack of skills 2.10 1.002 Lack of knowledge on how to do PA 2.15 0.892 Friends tease me during PA/sports 1.69 0.902 Too overweight to do PA 1.55 0.957 Physical activity is too much work 1.88 0.878 I do not like how my body feels when I do PA 1.90 1.013 Being active is physically uncomfortable 1.84 0.966 Physical activity is too hard 1.60 0.776 Perceived barrier-external I have too much homework 3.00 1.067 Lack of time 2.28 0.941 Weather is too bad 2.46 0.921 Lack of a convenient place to do PA 2.35 1.051 Lack of equipment 1.88 1.033 Do not have anyone to do PA with me 2.39 1.259 I’m chosen last for teams 2.14 1.242 No one at my skill level to do PA with me 2.14 1.118 Friends don’t like to do PA 2.34 1.180 Self-efficacy-internal Possess the skill to be physically active 3.12 1.083 Able to be physically active in most of the day after school 3.13 1.056 Able to be physically active despite how busy on that day 2.75 1.011 Able to be physically active no matter how tired I am 2.57 1.085 Able to be physically active outdoor whether it is hot or cold 2.70 1.132 Able to be physically active although I have a lot of homework 2.52 1.061 Able to be physically active after school although I can watch TV 2.86 1.099 or play video or computer games Able to be physically active although I have to be at home 3.06 1.039 Able to be physically active although I prefer to do other things 2.90 0.984 Able to be physically active although my friends disapprove 2.91 1.073 2.88 0.992 Able to be physically active although my friends want me to do other things Able to be physically active at least three times a week for the 3.11 1.100 coming 2 weeks Self-efficacy-external Can ask my parents or other adults to register me for sports, 2.98 1.164 dance, or other physical activities Can ask my parents or other adults to send me to physical training 2.98 1.164 session or sports Can ask my friends to be physically active with me 3.37 1.033 Can ask my parents or other adults to be physically active with me 3.12 1.142 Can ask my parents or other adults to obtain the equipment that I 2.94 1.113 need for PA 2.58 0.870 Peer influence Family influence 2.66 0.854 53.10 7.149 Beliefs in physical activity outcomes Body size discrepancy score 1.18 0.895 Body part satisfaction 33.54 5.86 Significant at p < 0.05.
a
Males (n = 49)
Females t (n = 96) statistics
SD Mean
df P-Value
SD
1.73 0.953 1.69 1.084 1.96 1.241 1.57 0.816 1.82 1.112 1.88 0.949 1.65 0.925 1.57 1.000 1.78 0.941 1.82 1.167 1.81 1.085 1.53 0.739 3.10 1.104 2.22 0.919 2.67 0.966 2.27 1.095 2.16 1.087 2.20 1.224 2.10 1.279 2.08 1.187 2.29 1.190 3.20 1.354 3.27 1.271 3.59 1.117 3.24 1.315 3.41 1.273 3.55 1.062 3.61 1.096
1.91 1.96 2.27 2.03 2.24 2.29 1.71 1.54 1.94 1.95 1.85 1.64 2.95 2.31 2.35 2.40 2.50 2.48 2.17 2.18 2.36 2.86 2.83 3.25 3.06 2.70 2.90 2.89
0.895 1.015 1.090 1.100 0.915 0.832 0.893 0.939 0.844 0.927 0.906 0.796 1.050 0.955 0.882 1.031 1.095 1.273 1.228 1.086 1.180 1.042 1.083 0.973 1.044 0.942 1.031 0.950
–1.068 –1.450 –1.553 0.822 –0.532 1.996 –0.706 –2.584 –2.447 –1.755 –2.700 –1.247 –0.296 –0.485 –0.380 –0.348 0.177 –1.051 –0.735 –0.243 –0.768 1.672 2.141 1.902 0.909 3.800 3.583 4.134
145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145 145
0.006a 0.064 0.162 0.007a 0.004 a 0.000a 0.000a
3.14 1.061 3.04 1.040 3.14 1.291 2.92 1.057
2.55 2.32 2.47 2.32
0.928 1.031 0.973 1.010
3.454 3.954 3.522 3.304
145 145 145 145
0.001a 0.000a 0.001a 0.001a
0.287 0.149 0.123 0.011a 0.016a 0.008a 0.728 0.860 0.295 0.464 0.808 0.444 0.413 0.596 0.048a 0.481 0.081 0.215 0.768 0.628 0.705
3.12 1.184 2.72 1.033
2.117 145 0.036a
3.31 1.176 2.93 0.943
2.102 145 0.037a
3.18 0.972 2.75 0.962
2.558 145 0.012a
3.24 1.217 2.74 0.954 3.22 1.066 2.70 0.908 3.49 1.227 2.92 0.981
2.742 145 0.007a 3.113 145 0.002a 3.052 145 0.003a
3.00 0.860 2.80 0.861 54.43 7.760 0.96 0.89 34.90 5.65
2.36 2.58 52.43 1.29 32.85
0.797 0.847 6.759 0.82 5.88
4.42 1.422 1.603 2.142 2.006
145 145 145 145 145
0.000a 0.157 0.111 0.034a 0.047a
Cheah et al.: Physical inactivity among rural adolescents in Borneo 5
For self-efficacy assessment, only six of 17 items had a mean score of 3.0 and above (i.e., “possess the skill to be physically active”, “able to be physically active in most of the day after school”, “able to be physically active although they have to be at home”, “able to be physically active at least three times a week for the coming two weeks”, “can ask the parents or other adults to be physically active”, “can ask friends to be physically active”). The rest of the items received mean scores that were more than 2 but less than 3. Males had more positive self-efficacy in PA compared with females, thus supporting our hypothesis. The differences between males and females were also significant for all items under self-efficacy except two items (“able to be physically active in most of the days after school” and “able to physically active despite a busy schedule on that day”). In terms of social influence for PA, overall, family had a stronger influence on PA compared with peers (2.66 ± 0.86 vs. 2.58 ± 0.87). However, peers have greater influence on males than females in terms of PA (3.00 ± 0.86 vs. 2.36 ± 0.80, p < 0.001). Males also had stronger beliefs in PA outcome compared with females (54.43 ± 7.76 vs. 52.43 ± 6.76). However, the difference was not significant (p = 0.111). In the perception of body size, males demonstrated less discrepancy between perceived current body size and perceived ideal body size, compared with the females. This indicated that males were more satisfied with their body size. This difference was found to be significant (p = 0.034). Similar for body parts satisfaction, males were more satisfied with their body parts compared with females (34.9 ± 5.65 vs. 32.85 ± 5.88, p = 0.047).
Discussion Based on a review by Tudor-Locke et al. (14), the recommended standard steps for children and adolescents should be in the range of 8000 to 16,000 steps per day. The present study showed that the mean steps per day was 6251.37 (SD = 3085.31), a low level compared with the international standards. In addition, both males and females did not meet the respective recommended. This study indicated there was a high level of physical inactivity among the studied population – a common phenomenon among adolescent boys and girls. This is consistent with a study carried out in Taiwan (17), which also reported that girls were less active compared with boys, supporting the findings of the current study. Asians generally valued academic performance as the most important aspect in their
life. In Korea, participation of adolescents in PA was low due to overload of homework and their academic-centered lifestyle (18). Some even attend tuition classes after school in order to achieve better grades. Nevertheless, there is also an increasing trend of children who spend a lot of time on computer games, smart phones, and television viewing at home (19). This phenomenon is not only affecting the urban adolescents but also rural adolescents (20). In our study, females reported body consciousness as a barrier to PA compared with males. Females were more body conscious and concerned about others seeing their bodies while performing PA. They were also less interested in vigorous PA, which was more favored by males. The findings of this study is consistent with those reported by Allison et al. (11). On the one hand, a possible reason highlighted by Allison et al. (11) is that females are usually given additional domestic/family responsibilities at home. This is plausible as in our rural setting, young females are expected to assist in house chores while their parents are out working and are expected to be back only at night. This is consistent with a study in Iran where female students were expected to take more responsibility in doing housework, limiting their PA involvement and time for doing exercise (21). On the other hand, male adolescents are more prone to moderate and high intensity activities that suit their physical and mental well-being, hence, they tend to have positive belief in PA outcome. This is further reflected in the subsequent findings where male adolescents were more satisfied with their body size and parts in comparison with female adolescents. Adolescence is a critical period of time when individuals are more aware of their bodily cues and self-reflection in terms of their body and appearance. Between genders, females are often concerned about body shape and are always not satisfied with their appearances although they are normal in weight. Furthermore, all female adolescents in this study were experiencing pubertal changes that might cause the increase in weight and proportion of fat. Such discontent in their expectation and body parameters was reflected the increase in discrepancy score between body size and ideal. By contrast, the male adolescents in our study were undergoing maturity, thus gaining muscle mass that approach their ideal body size and parts. Of all the perceived external barriers to PA, “too much homework” was considered one of the highest, with males’ slightly higher than females’. Other external barriers were perceived within mean scores of 2.08 to 2.67, with a mixture of lower and higher scores between males and females. Literature suggested that adolescents deciding to be physically active or not are influenced by environmental and social factors (19, 20, 22). Therefore, a condusive
6 Cheah et al.: Physical inactivity among rural adolescents in Borneo
environment would reinforce their habits to prefer doing more PA than be sedentary. Nevertheless, the intrinsic need of an individual can overcome the external barriers to be more physically active. This is quite possible because adolescence is the time when they are more conscious about their physical appearance, which is hinged upon their self-esteem. The findings from this study indicated that self-efficacy to PA is consistently higher among males compared with females. This is consistent with Robbins et al. (23). According to Social Cognitive Theory (SCT) by Bandura (24), self-efficacy is a central influence on exercise behavior. If applied in this context, high self-efficacy motivates PA. Therefore, as evidenced by Sallis et al. (25), interventions that build perception of self-efficacy can increase PA in young adults. Nevertheless, recent studies suggested that the decline in PA are inversely associated with self-efficacy for overcoming barriers to PA and perceived support from peer and family (26). In other words, individuals with high self-efficacy tend to have a greater decline in PA if they perceived declines in social support (peer or family). Though this study did not investigate the mediating or moderating effect of self-efficacy on PA and perceived social support, the mean scores for both peer and family support were higher among male adolescents compared with females. Two limitations of the present study should be noted: (a) sample bias, that is, because the participation of the study was voluntary, the study may have attracted those
who are interested in PA, and (b) respondents included in this study represented students in rural areas of Sarawak, thus the findings cannot be generalized beyond those in similar groups. Despite these limitations, findings of this study indicated the importance of interventions for this group of young population before they reach adulthood. Given that the level of PA is low for both genders, particularly among females, more intensive efforts should be considered in any of the public health policies and programs implemented for this group. In addition, to design effective intervention programmes, there should be attempts to reduce barriers to PA, increase self-efficacy and belief in PA outcome, and strengthen social support, in order to help our adolescents be healthier and more physical. The study also showed that self-efficacy plays an important role in promoting PA. The involvement of PA can be further improved with the support from one’s family, peers, and community. Acknowledgments: This work was supported by a grant from the Sarawak Heart Foundation. This study is registered at Universiti Malaysia Sarawak under Research Grant No. GL(F05)/10/2012/HF (10). Conflict of interest statement: None.
Received August 23, 2013; accepted November 24, 2013
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