Prevalence of short sleep duration and its association with obesity among adolescents 15- to 19-year olds: a cross-sectional study from three major cities in Saudi Arabia

Adequate sleep has been considered important for the adolescent's health and well being. On the other hand, self-imposed sleep curtailment is now recognized as a potentially important and novel risk factor for obesity. The present study aimed to assess the prevalence of short sleep duration and its association with obesity among Saudi adolescents. This is a school-based cross-sectional study with self-reported sleep questionnaires. It was conducted during the years 2009/2010 in three cities in Saudi Arabia; Al-Khobar, Jeddah, and Riyadh. Participants were 2868 secondary-school males [1379] and females [1389] aged 15 to 19 years, randomly selected using a multistage stratified sampling technique. Measurements included weight, height, waist circumference, BMI, and sleeping duration. Logistic regression analysis while adjusted for age, gender, and location was used to examine the associations between sleep duration and obesity measures. The mean [SD] of sleep duration was 7.2 [1.6] hours/day with no significant differences between males and females. About 31% of the participants obtain less than 7 hours of sleep per day, while approximately 50% of the sample gets less than 8 hours of daily sleep. Two-way ANCOVA results while controlling for the effect of age revealed a significant gender by school-type interaction [P<0.001]. In addition, adequate sleep duration increased the odds of having normal weight [adjusted odds ratios = 1.28, 95% CI = 1.08-1.50, P = 0.003]. The present study observed a high prevalence of short sleep duration among Saudi adolescents 15- to 19-year olds and that short sleep duration was significantly associated with increased risk of overweight and obesity. Future interventions should investigate whether adopting a healthy lifestyle by adolescents with short sleep duration would improve their sleeping habits or not

Adiposity and physical activity levels among preschool children in Jeddah, Saudi Arabia

To assess the levels of adiposity and physical activity among Saudi preschool children from Jeddah. Participants included 224 Saudi preschool children, randomly selected from public and private preschools in Jeddah during April and May of 2006, using a multistage stratified sampling technique. Measurements included weight, height, body mass index, triceps and subscapular skinfolds, fat percentage, fat mass [FM], fat-free mass [FFM], FM index [FMI] and FFM index [FFMI], time spent watching television and physical activity levels using electronic pedometer for 3 continuous days during weekdays. The fat content averaged 20.6% of body weight, while the prevalence of obesity was 10.8%. There were significant gender differences in fat percentage, FM, FFM, FMI, and FFMI. The mean value for pedometer-determined steps counts for the preschool children was 6773.2 steps per day. Boys were significantly more active than girls. Only 22.4% of the preschool children had 10000 steps or more per day. There were no significant age differences in skinfolds measurements, fat percentage, FMI, FFMI, central obesity or daily steps counts. Television viewing time increased by 22.5% from age 4 to age 6. Compared to non-obese, obese preschool children were significantly heavier, taller and had higher values for all adiposity indices and television viewing time. A considerable proportion of Saudi preschool children is obese and even a greater proportion is physically inactive. Obesity and physical inactivity represent major risks for a number of non-communicable diseases, and an early intervention is most appropriate

School backpack. How much load do Saudi school boys carry on their shoulders?

To investigate the percentage of body weight represented by school backpacks, to determine the dimensions of school packs, and to identify the methods of carrying book bags by elementary school boys. A cross-sectional study, using a multistage random sampling technique, was conducted during the Spring of 2005. Six elementary schools from Riyadh were included involving 702 Saudi boys in grade 1-6. Measures included body mass, height, biacromial and bi-iliac breadths, triceps and subscapular skinfolds, calculated fat percentage, school bag weight and dimensions. Students were also asked to respond to questions related to how they travel to and from school, how they carry the bag, and if they have pain due to bag carriage. Body fat percentage increased from 14.2% in the first graders to 24.6% in the sixth graders. The increase in body dimensions, however, was less than the increase in the fat percentage. School bag averaged 3.2 kg in absolute weight and 10.7% relative to student's body mass. Nearly 50% of the sample carried backpacks weighing more than 10% of their weight. Bag surface area averaged 1.05 m2 while the ratio of bag surface area to student's trunk area ranged from 129% in the first graders to 81% in the sixth graders. Approximately 29% of the students walk to and from school. More than 65% of the sample carried their bags over one or 2 shoulders, 20% used single strap bags carried by one hand and 14.5% had bags with wheels. Over one third of the students reported experiencing bodily pain due to bag carriage. A considerable proportion of Saudi school boys carried an overloaded and oversized backpacks. Moreover, one third of the sample experienced bodily pain related to school bags. It is recommended that school bags be limited to no more than 5-10% of student's body weight

Normal isometric and isokinetic peak torques of hamstring and quadriceps muscles in young adult Saudi males

To provide reference data for peak isometric and isokinetic muscle strength of hamstring and quadriceps muscles in young adult Saudi males. The strength of left and right quadriceps and hamstrings leg muscles was assessed in 132 college-male students in the campus of King Saud University, Riyadh, Kingdom of Saudi Arabia in the year 2002 using a Cybex machine and a standardized protocol at the following velocities: 0, 60, 180, and 300 °/sec. Isometric strength [0°/sec] was assessed at 65o angle of knee flexion. Isometric flexion strength was 9.3% higher in the right leg compared to the left [p < 0.01], while there was no significant difference between the 2 legs in extension. In isokinetic strength, there was a decrease in both extension and flexion strength with increasing velocity. However, only in flexion strength a significant right-left difference was observed. Flexion/extension peak concentric torque ratio relative to angular velocity varied from 59.9-63.3% in the right leg and from 55.8-59.9% in the left leg, with significant difference [p < 0.02] between the 2 legs. In addition, the angle of peak torque decreased with increasing velocity at knee extension but increased at knee flexion. Young Saudi males appeared to have similar isometric peak strength in the knee extensors but not in the flexors when compared to previously published research. Isokinetic extension strength at 60°/sec in the Saudi males is lower than values reported for untrained males elsewhere. Furthermore, the hamstrings/quadriceps ratio in Saudi males seems to be within the recommended range of appropriate muscle function

Cardiopulmonary exercise testing. an underutilized diagnostic tool in Saudi Arabia

To assess the use of cardiopulmonary exercise testing [CPET] in major hospitals and medical centers throughout the Kingdom of Saudi Arabia [KSA] and to seek information on the way CPET is conducted. Self-reported questionnaires on the use of CPET were mailed during the fall of 2002 to 54 major public and private hospitals and medical centers throughout the KSA. The response rate was 64.2%. The returned questionnaires were coded and data were analyzed. The findings indicated that more than 85% of the sample was not employing CPET in their medical centers. However, all of the surveyed centers were regularly performing stress electrocardiogram tests. Approximately 21% of those medical centers who did not have CPET are planning to have it in the near future. The most frequent reasons for not conducting CPET were lack of equipment, lack of trained technicians and lack of training in interpreting test results. Moreover, the most important reasons for conducting the CPET were pulmonary problems, followed by cardiac disorders. Treadmill and leg ergometer were used most as an exercise mode. Bruce protocol as well as institution specific protocols were equally used during CPET. Finally, there appears a lack of local cardiorespiratory data, especially for healthy Saudi females at all ages as well as older male group. Cardiopulmonary exercise testing as a diagnostic tool for cardiopulmonary diseases was extremely underutilized in Saudi hospitals and medical centers. Much greater efforts are needed to raise the awareness among physicians on the usefulness of CPET

Echocardiographic dimensions and maximal oxygen uptake in elite soccer players

To assess cardiac dimensions in elite Saudi soccer players, and to correlate these measurements with maximal oxygen uptake. Twenty-three soccer players representing the Saudi National soccer team, and 19 untrained males participated in this study. Cardiac dimensions were measured by M-mode echocardiography, and maximal oxygen uptake was assessed by open-circuit spirometry during treadmill running. When compared with age-matched untrained males, soccer players appeared to have significantly [P<0.05] greater values [mm.m-2] in left ventricular end-diastolic dimension [28.8 +/- 2.7 vs 26.5 +/- 2.3], right ventricular cavity [14.1 +/- 2.5 vs 11.8 +/- 2.6], left atrial cavity [16.7 +/- 1.6 vs 14.9 +/- 2.2] and left ventricular mass [117.4 +/- 21.2 vs 89.0 +/- 16.0 g.m-2]. There was no significant difference between the 2 groups in left ventricular posterior wall [5.3 +/- 0.77 vs 5.3 +/- 0.61] or in interventricular septum [5.5 +/- 0.65 vs 5.2 +/- 0.59]. When soccer players were grouped by playing position, there were no significant differences in cardiac dimensions between the players, though the midfielders and the full-backs showed the highest values for left ventricular cavity and maximal oxygen uptake. Further, maximal oxygen uptake relative to body mass [ml.kg.-1 min-1] exhibited a significant correlation with left ventricular cavity normalized to either body mass [r = 0.62; P <0.01], or to body surface area [r = 0.53; P < 0.05]. The elite Saudi soccer players appear to have significantly greater left ventricular cavity and mass than age-matched untrained males. Such cardiac adaptation seems to result from the highly dynamic nature of the soccer game

Echocardiographic studies in Saudi athletes

M-mode and two-dimensional echocardiograms were carried out on 334 Saudi athletes in different sporting activities during the peak of their training seasons. They were compared with 25 age-matched controls comprised of men who were not involved in any systematic sporting activities. The findings of this study indicate that, while controlling for body surface area, the athletes had, in general, higher mean values in all of the measured cardiac parameters when compared with the controls. The differences were especially significant for the thickness of the left ventricular posterior wall and the interventricular septum. However, athletes such as tennis players and high jumpers who were known not to train vigorously did not have values higher than the controls. The results showed that the septal hypertrophy observed was not of that nature as to obstruct the left ventricular outflow tract as found in obstructive cardiomyopathy and is therefore not likely to contribute to sudden death in athletes. The data obtained in this study were compared with those found in athletes of some other countries

Maximal oxygen uptake, ventilatory anaerobic threshold and endurance performance in Saudi distance runners

To examine the relationship between maximal oxygen uptake [VO[2] max], ventilatory anaerobic threshold [VAT], and endurance running performance Twelve trained Saudi male distance runners completed a 15 km running race, and were later tested in the laboratory to determine their VO[2] max and VAT. Cardiorespiratory and metabolic parameters were assessed during a graded treadmill test using an automated open-circuit spirometry; VAT was determined by gas exchange method. The findings of this study indicated that the elite Saudi runners had a mean VO[2] max of about 71 ml/kg min. It was also shown that VO[2] max had a moderately strong correlation with 15 km running time [r= -0.69]. However, VAT had a much higher correlation with the 15km running time [r= -0.82]. Furthermore, VO[2] max relative to body weight was shown to be strongly correlated with VAT [r=0.92] A 1 5 km endurance performance is more closely associated with VAT than with VO[2] max in elite long-distance runners

Prevalence of coronary artery disease risk factors in Saudi Children

Two hundred and twenty boys, 7 to 12 years of age, were subjected to a comprehensive medical, anthropometric, and physiological evaluation to assess the prevalence of coronary artery disease risk factors. These risk factors include obesity, blood lipids and lipoproteins, blood glucose, blood pressure, cardiorespiratory fitness, and physical activity level. The results of this study indicate that there are no significant age-related differences in total cholesterol, triglycerides, LDL-cholesterol, HDL-C/cholesterol ratio, or blood glucose. No significant hypertension was detected among the subjects. Using relative body fat, 15.6% of the boys were considered obese. Body fat percent showed significant inverse relationships with cardiorespiratory fitness, HDL-cholesterol, HDL-C/cholesterol ratio, and was related positively to systolic and diastolic blood pressures but not to total cholesterol. Blood pressure was not related to cholesterol or triglyceride levels. The findings of this study also showed that 22.9% of the boys exceeded cholesterol level of 5.2 mmol/L, 26.4% had triglyceride level above 1.4 mmol/L, 15.4% had a LDL-cholesterol level above 3.4 mmol/L, and 4.0% had HDL-cholesterol below .96 mmol/L. We conclude that a considerable percentage of the tested schoolchildren between the ages of 7 and 12 years have one or more coronary artery disease risk factors

Physical growth and development of Saudi adolescents: a cross sectional study

An attempt was made to describe the patterns of growth and development of Saudi adolescents between the ages of 12 and 17 and to compare their results with their non-Saudi counterparts. 218 Saudi and 57 non-Saudi boys were randomly selected from Intermediate schools in the City of Riyadh. Measurements of height, weight, grip strength and the circumferences of shoulder, chest, abdomen, buttock, thigh, calf, ankle, arm, forearm and wrist were taken. Results indicated that Saudi boys appeared to have lower measurements than that of non- Saudi's, though the differences were only significant at age 13. A comparison with available data from world population was also made