El Ghali Bouhafs

Background: The relationship between physical activity (PA), health-related physical performance (PP), and academic achievement (AA) plays an important role in childhood. This study examined the differences in PA, sedentary behavior, health-related PP, maturity status, and AA between normal-weight and obese school children in Qatar. Methods: Eighty schoolchildren were recruited (age: 12.1 ± 0.6 years). Based on age-specific BMI percentiles, the children were classified as normal weight (n = 40) or obese (n = 40). Moore’s equations were used to estimate their maturity status (PHV). The measurements encompassed anthropometric data as well as PP tests (medicine ball throw, postural stability, handgrip strength). AA was assessed by reviewing school records for grade point average in Mathematics, Science, and Arabic courses. The total amount of time spent participating in PA each week was calculated using the International Physical Activity Questionnaire Short Form. Results: Handgrip strength was the only parameter that showed a relevant group difference (p < 0.001, η_p² = 0.15; normal weight: 19.7 ± 3.46 N; obese: 21.7 ± 2.80 N). We found only one moderate correlation between PHV and handgrip strength (r = 0.59). Conclusions: The findings suggest that obesity status alone might not serve as a sufficient predictor of AA in school or PA levels.

This study examined the effects of 8 weeks of twice-weekly combined plyometric and sprint with change-of-direction (CPSCoD) training into habitual training regimes of young male soccer players. Participants were randomly allocated to an experimental group (n = 17, age: 14.6 ± 0.44 years, body mass: 61.2 ± 7.34 kg, height: 1.67 ± 0.09 m, body fat: 11.2 ± 1.56%) and a control group (n = 16, age: 14.6 ± 0.39 years, body mass: 61.1 ± 3.96 kg, height: 1.67 ± 0.05 m, body fat: 11.8 ± 1.47%). Measures obtained pre- and post intervention included vertical and horizontal jump performance (i.e., squat jump (SJ), countermovement jump (CMJ), and standing long jump (SLJ)), and sprint performance (i.e., 5 m and 20 m sprint). In addition, Measures obtained pre- and post-intervention included change-of-direction ability (4 × 5 m sprint test (S 4 × 5 m) and sprint 9–3–6–3–9 m with backward and forward running (SBF)), repeated change of direction (RCoD), and static balance performance (stork balance test). The training group experienced superior jump (all p < 0.05; d ≥ 0.61), sprint (all p < 0.05; d ≥ 0.58), change-of-direction (CoD) ability (all p < 0.05; d ≥ 0.58), RCoD (all parameters except the fatigue index p < 0.01; effect size (d) ≥ 0.71), and static balance (all p < 0.05; d ≥ 0.66) improvement. Adding twice-weekly CPSCoD training to standard training improves the anaerobic performance of U15 male soccer players.

We investigated adding 8 weeks of bi-weekly loaded plyometric and short sprints (LPaSS) training into training for under 19 (U19) soccer players. An experimental group (EG, n = 18, age: 17.5 ± 0.58 years, body mass: 67.4 ± 4.37 kg, height: 1.76 ± 0.05 m, body fat: 11.4 ± 1.55%), and a control group (CG, n = 16, age: 17.5 ± 0.58 years, body mass: 68.7 ± 3.65 kg, height: 1.78 ± 0.03 m, body fat: 11.6 ± 1.14%) participated. The pre- and postintervention measures were: the squat-jump (SJ); the countermovement-jump with arm swing (CMJA); the five jump test (5JT); 10 m and 30 m sprint; the ability to change direction (sprint with 90° turns (S90°) and sprinting 9–3–6–3–9 m, involving running both backwards and forwards (SBF); repeated sprint ability (RSA), and balance (Y-balance test). The EG experienced superior jump (p < 0.001; d_range: 1.69–1.89), sprint (p < 0.001; d_range: 1.82–2.56), S90° (p < 0.001; d_range: 1.64–2.25), RSA (p < 0.001; d_range: 3.90–4.17), and balance (p < 0.001; d_range: 1.11–2.54) improvement. Comparatively, the pre- to postchanges in the CG ranged from d = 0.36 (dynamic balance) to d = 1.00 (10 m sprint). Therefore, bi-weekly LPaSS training improves athletic performance in young soccer players, particularly RSA.

This project investigated effects of 8 weeks of biweekly loaded combined plyometric and short sprint with change-of-direction training an in-season regimen of young soccer players. An experimental (n = 17, age: 16.5 ± 0.5 years, body mass: 64.5 ± 5.2 kg, height: 1.73 ± 0.07 m,) and control group (n = 17, age: 16.7 ± 0.5 years, body mass: 65.6 ± 4.8 kg, height: 1.74 ± 0.07 m) were tested pre- and post-intervention for squat-jump (SJ), countermovement-jump (CMJ), and five-jump test (5JT), 10 m and 30 m sprint performance, change-of-direction ability, and dynamic balance performance. The experimental group (EG) outperformed the control group (CG) over 8 weeks in jumping (p < 0.001; d = 0.98–1.17), 10 m sprinting (p < 0.001; d = 0.94), change-of-direction ability (p < 0.001; d = 1.24), and dynamic balance performance (p < 0.001; d = 0.53–0.74). We conclude that adding biweekly loaded plyometric with short sprints and change-of-direction training to habitual training improves athleticism of young soccer players. Therefore, loaded plyometric with short sprints and change-of-direction training should be implemented as a part of research-informed soccer training.

This project investigated the effect of adding 8 weeks of bi-weekly plyometric and short sprint with change-of-direction (PSSCoD) training into standard training for elite youth soccer players from Tunisia. A training group (n = 18; age: 16.6 ± 0.5 years; body mass: 63.2 ± 4.8 kg; stature: 1.73 ± 0.07 m; body fat: 11.2 ± 1.7%), and control group (n = 16; age: 16.6 ± 0.5 years; body mass: 63.6 ± 4.3 kg; height: 1.73 ± 0.06 m; body fat: 11.6 ± 1.5%) participated. The pre- and post-intervention measures were squat-jump (SJ), countermovement jump (CMJ), standing long jump (SLJ), 5 m and 20 m sprint, change-of-direction ability (4 × 5 m sprint test (S 4 × 5 m)), repeated sprint ability (RSA), and static balance (stork balance test). The training group displayed superior jump (all p < 0.05; d > 0.49), sprint (p < 0.05; d > 0.52), change-of-direction ability (p < 0.01; d = 0.78), RSA (p < 0.01; d > 0.70), and static balance (p < 0.05; d > 0.49) improvements. Adding bi-weekly PSSCoD improves the athletic performance of young soccer players.

This study investigated effects of home confinement on physical activity (PA) in Team Handball during the COVID-19 outbreak. A total of 1359 handball players participated (age: 23 ± 6 years). Participants from Europe, Western Asia, and North Africa answered an online version of the International Physical Activity Questionnaire (IPAQ) considering “before” and “during” confinement. COVID-19 home confinement has had a negative effect on PA (vigorous, moderate, walking, and overall). The largest decrease was in the sum parameter “all PA” (MET (metabolic equivalent of task)-min/week, η_p² = 0.903; min/week, η_p² = 0.861). Daily sitting time increased from 2.7 to 5.0 h per weekday (p < 0.001, η_p² = 0.669). For gender, continent, country, level of handball league, and playing position, no significant differences (group and interaction effects) were observed. The largest change in PA behavior was in walking (minutes per day: η_p² = 0.755), with males displaying the greatest decrease (from 62 ± 11 to 30 ± 14 min per weekday; d = 2.67). In terms of magnitude, difference between genders was greatest for sitting time (difference in d = 1.20). In conclusion, while COVID-19 measures were essential to preserve public health, PA was compromised and sedentary behavior increased because of these public health measures regardless of gender, playing position, and competition level.

This study examined the effects of home confinement on physical activity (PA) and life satisfaction during the COVID-19 outbreak in Qatar. A total of 1144 subjects participated (male: n = 588; female: n = 556; age: 33.1 ± 11.1 years; mass: 76.1 ± 16.4 kg; height: 1.70 ± 0.11 m; body mass index (BMI): 26.1 ± 4.44 kg/m²). Online survey questions considered “before” and “during” confinement. Confinement reduced all PA intensities (η_p² = 0.27–0.67, p < 0.001) and increased daily sitting time from 3.57 ± 1.47 to 6.32 ± 1.33 h per weekday (η_p² = 0.67, p < 0.001). The largest reduction was detected for the sum parameter all physical activity (minutes per week, η_p² = 0.67, p < 0.001; MET (metabolic equivalent of task)-minutes/week, η_p² = 0.69, p < 0.001). Life satisfaction decreased, with the score for “I am satisfied with my life” (η_p² = 0.76, p < 0.001) decreasing from 28.1 ± 4.81 to 14.2 ± 6.41 arbitrary units (AU). Concerning life satisfaction, the largest change was detected for the statement “the conditions of my life are excellent” (d_male = 7.93). For all parameters, time effects were indicative of large negative effects in both genders. In terms of magnitude, the difference between gender was greatest for the parameter “the conditions of my life are excellent” (difference between groups, d = 4.84). In conclusion, COVID-19 confinement decreased PA, increased sitting time, and decreased life satisfaction in Qatar. These precautionary findings explicate the risk of psychosocial impairment and the potential physical harm of reducing physical activity during early COVID-19 confinement in 2020.

This study aimed to compare 10-to-12-year-old Qatari male athletes and assess body fat, body mass index, and physical fitness, as well as the difference of these measures between ages. Thirty-five youth handball players volunteered for the investigation and were divided into three groups: 12-year-old players (U12; n = 12), 11-year-old players (U11; n = 11), 10-year-old players (U10; n = 12). Anthropometry was assessed by body mass, body fat percentage (%BF), and body mass index (BMI). Measurements included the Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1), jumping ability (squat and countermovement jumps (SJ and CMJ, respectively)), and sprint tests (10 and 15 m). The power of the upper extremity was measured by a 2-kg overhead medicine ball throw for distance. Except for %BF (p = 0.387) and BMI (p = 0.070), all anthropometric and demographic parameters were different between age groups. The largest differences were found for body mass (p = 0.007) and body height (p = 0.008). Regarding fitness parameters, only the medicine ball throw (p = 0.022) was different between age groups (U10 vs. U12: p = 0.009; U11 vs. U12: p = 0.048). There was no difference between groups for jumping (CMJ: p = 0.586; SJ: p = 0.377), sprinting (10 m: p = 0.211; 15 m: p = 0.194) and Yo-Yo IR1 (p = 0.228). Body fat was the anthropometric parameter with the strongest relationship with physical performance in that lower body fat was related to superior jumping performance and sprint performance. In conclusion, except for %BF and BMI, all anthropometric parameters were different between U10, U11, and U12 handball players. For physical parameters, jumping, sprinting, and endurance performance were not different between age groups. From a practical perspective, coaches can use these findings as reference for the evaluation of their school-aged handball players, as well as for establishing performance goals.