Effects of Ramadan on cognitive functions in young boys.

Fasting during Ramadan involves abstaining from food and drink from dawn to sunset, potentially influencing cognitive functions essential for the intellectual development of the youth. Therefore, understanding the effects of fasting on these functions in children/adolescents provides valuable perspectives to enhance education and promote mental well-being. However, studies on children/adolescents in this context are still limited. To evaluate the impact of Ramadan fasting on cognitive functions, including information processing speed, inhibition, decision-making, and auditory attention processes among children and adolescents aged 11 to 15 years. This study was conducted with 24 healthy children/adolescents (aged 12.84 ± 0.69 years). The experimental protocol consisted of two sessions: Before-Ramadan (BR) and at the beginning of the second week of Ramadan (R2). At each session, the boys were randomly tested on simple reaction time (SRT), choice reaction time (CRT), negative priming reaction time (NPRT), and auditory discrimination (P300). The tests were administered and scored by the same person in the different sessions. The study found that Ramadan fasting did not have an effect on various reaction times or on electro-physiological data, including P300 amplitude and latency. The current study, conducted with healthy children/adolescents, indicates that Ramadan fasting had no impact on various reaction times (SRT, CRT, NPRT), suggesting the preservation of information processing speed and decision-making, even in the face of increased task complexity. This is evident, on the one hand, through the maintenance of the ability to react to unexpected events, and, on the other hand, through the mastery of resistance to automatism, thus reflecting the preservation of inhibitory function (NPRT). Regarding P300 data, the absence of changes in latencies and amplitudes suggests that Ramadan fasting did not alter either the evaluation time of auditory stimuli or auditory attention processes.

Effects of cardiorespiratory rehabilitation program on submaximal exercise in patients with long-COVID-19 conditions: a systematic review of randomized controlled trials and recommendations for future studies.

INTRODUCTION: Long-COVID-19 patients (LC19Ps) often experience cardiovascular and respiratory complications. Cardiorespiratory rehabilitation programs (CRRPs) have emerged as promising interventions to enhance exercise capacity in this population. This systematic review aimed to assess the impact of CRRPs on submaximal exercise performance, specifically the 6-minute walk test (6MWT) outcomes, in LC19Ps through an analysis of available randomized controlled trials (RCTs). METHODS: A systematic search was conducted in PubMed/Medline and Scopus to identify relevant RCTs. Six RCTs meeting inclusion criteria were included in this review, investigating the effects of CRRPs on 6MWT outcomes in LC19Ps. RESULTS: The findings from the included RCTs provide compelling evidence supporting the effectiveness of CRRPs in improving submaximal exercise performance in LC19Ps. These results underscore the potential of CRRPs to enhance submaximal exercise capacity and overall functional well-being in this population. However, future research is imperative to determine optimal CRRPs, including duration, intensity, and specific intervention components. Additionally, the long-term sustainability and durability of CRRP-induced improvements warrant further exploration. Future studies should prioritize patient-centric outcomes and address potential implementation barriers. CONCLUSION: CRRPs show promise in ameliorating submaximal exercise performance among LC19Ps. Further research is needed to refine these programs and ensure their lasting impact on this patient group. SYSTEMATIC REVIEW REGISTRATION: https://doi.org/10.17605/OSF.IO/HMN38. [Figure: see text].

ChatGPT for Sample-Size Calculation in Sports Medicine and Exercise Sciences: A Cautionary Note.

PURPOSE: To investigate the accuracy of ChatGPT (Chat generative pretrained transformer), a large language model, in calculating sample size for sport-sciences and sports-medicine research studies. METHODS: We conducted an analysis on 4 published papers (ie, examples 1-4) encompassing various study designs and approaches for calculating sample size in 3 sport-science and -medicine journals, including 3 randomized controlled trials and 1 survey paper. We provided ChatGPT with all necessary data such as mean, percentage SD, normal deviates (Zα/2 and Z1-ß), and study design. Prompting from 1 example has subsequently been reused to gain insights into the reproducibility of the ChatGPT response. RESULTS: ChatGPT correctly calculated the sample size for 1 randomized controlled trial but failed in the remaining 3 examples, including the incorrect identification of the formula in one example of a survey paper. After interaction with ChatGPT, the correct sample size was obtained for the survey paper. Intriguingly, when the prompt from Example 3 was reused, ChatGPT provided a completely different sample size than its initial response. CONCLUSIONS: While the use of artificial-intelligence tools holds great promise, it should be noted that it might lead to errors and inconsistencies in sample-size calculations even when the tool is fed with the necessary correct information. As artificial-intelligence technology continues to advance and learn from human feedback, there is hope for improvement in sample-size calculation and other research tasks. However, it is important for scientists to exercise caution in utilizing these tools. Future studies should assess more advanced/powerful versions of this tool (ie, ChatGPT4).

Evaluation of muscle strength and quality in North African patients with chronic hepatitis B: A pilot case control study.

Early detection of alteration of muscle strength, quantity, and quality, and sarcopenia is useful in non-cirrhotic chronic hepatitis B (NC-CHB) patients. Studies, which explored the handgrip strength (HGS) are scarce with questionable results, and no previous case-control study explored the presence of sarcopenia.The aim of this study was to assess the muscle strength [i.e.; HGS absolute (HGSA), HGSA/body mass index (BMI)], muscle quantity [i.e.; appendicular skeletal muscle (ASM), ASM/height2, ASM/total body weight (TBW), ASM/BMI], and muscle quality [i.e.; HGSA/total muscle mass (TMM), HGSA/ASM] of NC-CHB patients.This was a case-control study. Cases (n = 26) were untreated NC-CHB patients, and controls (n = 28) were 'apparently' healthy participants. Muscle mass was estimated via the TMM (kg) and ASM (kg). Muscle strength was evaluated via the HGS data [i.e.; HGSA (kg), HGSA/BMI (m2)]. Six variants of HGSA were determined: highest values for the dominant and non-dominant hands, highest value between the two hands, averages of the three measurements for the two hands, and the average of the highest values of the two hands. Muscle quantity was expressed in three relative variants (ASM/height2, ASM/TBW, and ASM/BMI). Muscle quality was evaluated via relative HGS data adjusted by muscle mass (i.e.; HGSA/TMM, HGSA/ASM). Probable and confirmed sarcopenia were retained in front of low muscle strength, and low muscle strength and muscle quantity or quality, respectively.There were no significant differences between controls and NC-CHB patients in values of muscle i) Strength whatever the HGS' mode of expression (e.g.; HGSA/BMI: 1.59 ± 0.54 vs. 1.53 ± 0.54 m2, p = 0.622, respectively), ii) Quantity (e.g.; ASM/BMI: 0.79 ± 0.24 vs. 0.77 ± 0.23 m2, p = 0.883), and iii) Quality (e.g.; HGSA/ASM: 2.00 ± 0.25 vs. 2.01 ± 0.41, p = 0.952, respectively). One NC-CHB participant had a confirmed sarcopenia.To conclude, both controls and NC-CHB patients had similar HGS values. Only one NC-CHB patient had a confirmed sarcopenia.

Prevalence and risk factors of functional gastrointestinal disorders in early period medical students: a pilot study in Tunisia.

Functional gastrointestinal disorders (FGIDs) are highly prevalent in medical students around the world. However, there is no specific data on FGIDs in Tunisia. The objectives of this study were to evaluate the prevalence of FGIDs in medical students according to the rome III criteria and to identify risk factors associated with these disorders. A self-administered questionnaire survey was carried out among the students from the first and the second year of medical studies. We studied the influence of socio-demographic characteristics, lifestyle, health care seeking, psychosomatic symptoms and hospital anxiety and depression scale on the prevalence of FGIDs among these students. Three hundred and forty-three students (20.3 ± 0.8years) were included in our study. The prevalence of FGIDs was 54.2%. The main FGIDs found were the unspecified functional bowel disorder (46.6%), functional constipation (11.6%), irritable bowel syndrome (7.6%) and functional dyspepsia (6.7%). In logistic regression, abnormal BMI (OR = 2.1, 95% CI= 1-4.3), living in school dormitory (OR = 3.7, 95% CI = 1.7-7.8), low water intake (OR = 2.2, 95% CI = 1.1-4.2), digestive medication use (OR = 3.4, 95% CI= 1.3-8.5), and probable or definite anxiety (OR = 2.5, 95% CI = 1.1-5.8) were the five risk factors associated with FGIDs. We demonstrate a high prevalence of FGIDs (54.2%) among our students. Risk factors for FGIDs were abnormal BMI, living in school dormitory, low water intake, digestive medication use and anxiety.

Reversibility of pancreatic ß-cells dysfunction after vitamin D and calcium supplementation: a pilot study in a population of obese and prepubescent North-African children.

The mechanisms of diabetogenesis in children remain largely obscure. This study aimed to determine the impact of vitamin D and calcium supplementation on pancreatic ß-cells function in terms of insulin secretion and sensitivity. This was a quasi-experimental study involving 30 obese and prepubescent Tunisian children (57% boys). During three months, the children received calcium and vitamin D supplementation at therapeutic doses. An oral glucose tolerance test (OGTT) was performed at the beginning and at the end of the study. The following metabolic definitions were applied: i) hyperinsulinism: insulinemia sum > 300 µ UI/ml during OGTT, ii) insulin-resistance: homeostatic model assessment of insulin-resistance > 2, iii) normal glycaemic profile: normal plasma levels during OGTT without any spike, and iv) pancreatic ß-cells dysfunction reversibility: disappearance of the aforementioned disorders. The means ± standard-deviation of age and body mass index were 10.87 ± 1.9 years, and 30.17 ± 4.99 kg/m2, respectively. All children were at the stage of hyperinsulinism associated with insulin-resistance. These disturbances were noted even in children having a normal glycaemic profile at OGTT. After calcium and vitamin D supplementation, glycaemic profile as well as insulin-secretion improved significantly (p < 0.0001). Hyperinsulinism and insulin-resistance decreased significantly by 56.67% (p < 0.0001) and 70.00% (p < 0.0001), respectively. Complete reversibility of these two disorders was noted in 26.6% of children. To conclude, in obese and prepubescent children, vitamin D and calcium supplementation led to the reversibility of the pancreatic ß-cells dysfunction.

Deficiency, incapacity and social disadvantage of patients with chronic hepatitis B: a case-control study.

INTRODUCTION: Studies examining impairment, disability and social disadvantage of patients with chronic viral hepatitis B (CHB) are scarce and present conflicting conclusions. AIM: To assess the deficiency, incapacity, and social disadvantage of patients with CHB. METHODS: This is a project of a case-control study with two age-matched groups. Cases (n=27) will be untreated patients with a CHB. Controls (n=27) will be healthy participants. The following data will be collected: deficiency [anthropometric, biochemical (renal and hepatic functions, lipid balance, and inflammatory markers), haematological, virological, handgrip-strength, and spirometric data], incapacity [6-min walk distance, number of stops, oxy-haemoglobin saturation, dyspnoea (visual analogue scale), heart-rate, and blood-pressure] and social disadvantage ["chronic liver disease" and physical-activity questionnaires]. Each spirometric data < lower-limit-of-normal will be considered abnormal. A handgrip-strength <26 kg (male) or <16 kg (female) will be considered low. The signs of walking intolerance will be: stop during the walk, 6-min walk distance ≤ lower-limit-of-normal, dyspnoea at the end of the walk> 5/10, drop in oxy-haemoglobin saturation >5 points, heart-rate at the end of the walk ≤60%. A total physical-activity score <9.42 will classify the participant as sedentary. EXPECTED RESULTS: Compared with controls, cases will have a marked alteration of submaximal aerobic data. These alterations will worsen quality-of-life and may be related to muscle and/or spirometric abnormalities, and supported by systemic inflammation and high viral load.

In COVID-19 context : a look back at the transition to exclusive e-learning experiment and the engagement of medical students.

In a context of unprecedented pandemic, e-learning has emerged as the only possible alternative to pursue higher education. In this work, we carried out an experiment consisting in completely transforming a fundamental science course into e-learning via the tools offered by Moodle platform. The results were generally encouraging in terms of learning outcomes and evaluation. However, the lack of motivation and adhesion observed in part of the promotion remains the main obstacle universally criticized in this type of teaching.

Relationships of the 5-Jump Test (5JT) Performance of Youth Players With Volleyball Specific' Laboratory Tests for Explosive Power.

Volleyball involves movements with and/or without horizontal approaches (i.e., spike jumps, jump setting, blocking). The 5-jump test (5JT) was suggested to assess lower limb explosive power of athletes competing in some disciplines (e.g., soccer, judo, running). It appears that no previous study has investigated the 5JT performance components in volleyball players. This study aimed to test the relationship between 5JT performance and two specific laboratory tests for explosive power (i.e., countermovement jump [CMJ] and squat jump [SJ]). Forty volleyball players (boys, mean age: 12.4 ± 0.8 years) were tested for 5JT, CMJ, and SJ tests. 5JT performance was expressed in absolute terms (m), and relative to leg length (5JTLL) and body mass (5JTBM). The SJ and CMJ tests were evaluated using the optojump photoelectric cells and the following data were collected: peak power (Pp) of jump (W, W.kg-0.67), peak jumping force (Fpeak, N), peak jumping velocity (Vpeak, m/s), peak heights of CMJ and SJ (CMJH and SJH, respectively, cm). Only significant (p < .05) Pearson product-moment correlations (r) > 0.30 were considered. 5JT performance was significantly correlated with SJ, Vpeak (r = 0.90), SJH (r = 0.88), Pp [W.kg-0.67 (r = 0.86), W (r = 0.72)], Fpeak (r = 0.45); and CMJ, Vpeak (r = 0.82), CMJH (r = 0.80), Pp [W.kg-0.67 (r = 0.89), W (r = 0.85)], Fpeak (r = 0.73). 5JTLL values were significantly related to SJ, Pp [W (r = 0.81), W.kg-0.67 (r = 0.74)], Vpeak (r = 0.82); and CMJ, Pp [W (r = 0.73), W.kg-0.67 (r = 0.84)], Vpeak (r = 0.75), Fpeak (r = 0.67)]. 5JTBM values were significantly related to SJ, Pp (W, r = -0.43). To conclude, in youth volleyball players, the 5JT may be viewed as an explosive strength diagnostic instrument under field circumstances.

Does Ramadan Observance Affect Cardiorespiratory Capacity of Healthy Boys?

Studies raising the issue of the effects of Ramadan observance (RO) on boys' 6-min walk test (6MWT) data are rare. The studies, which did not include control groups of non-fasters, presented contradictory results. This study aimed to compare the 6MWT data (6-min walk distance [6MWD; m, %predicted], heart rate [HR; bpm, % of maximal predicted HR]), oxy-hemoglobin saturation (Oxy-sat; %), systolic and diastolic blood pressures (SBP and DBP, respectively; mmHg) determined at rest (Rest and at the end End of the test) of a group of 22 healthy fasting boys (age: 12 to 15 years) with an age-matched non-fasting group (n = 10). The 6MWTs were performed during three experimental conditions (ECs): Pre-Ramadan, Mid-Ramadan, and Post-Ramadan. The two groups' 6MWT data for each EC were compared, and repeated factorial analysis of variance (2 groups vs. 3 ECs) was performed. Both groups had similar values of 6MWD (m, %predicted), HRRest or HREnd (bpm, % of maximal predicted HR), Oxy-satRest, Oxy-satEnd, SBPRest, and DBPRest during the three ECs. Compared to the non-fasting group, the fasting group had significantly higher SBPEnd (121 ± 10 vs. 130 ± 11) and DBPEnd (72 ± 6 vs. 78 ± 7) determined during the Mid-Ramadan EC. No significant interactive effects of the groups (2) vs. ECs (3) was found for the 6MWD (%predicted; p = .809), HRRest (%, p = .555), HREnd (%, p = .964), Oxy-satRest (p = .336), Oxy-satEnd (p = .389), SBPRest (p = .708), SBPEnd (p = .548), DBPRest (p = .277), and DBPEnd (p = .096). To conclude, in boys, RO does not impact the 6MWD, HR, or Oxy-sat, but it has minimal impact on the SBPEnd and DBPEnd.

Does Ramadan Fasting Affect Spirometric Data of Healthy Adolescents?

PURPOSE: Several studies raised the effects of Ramadan fasting on healthy adults spirometric data, but none was performed in children. The aim of this study was to compare the spirometric data of a group of faster adolescents (n = 26) with an age-matched non-faster one (n = 10). METHODS: This comparative quasi-experimental study, including 36 healthy males aged 12 to 15 years, was conducted during the summer 2015 (Ramadan: June 18 to July 16). Three sessions (Before-Ramadan [Before-R], Mid-Ramadan [Mid-R], After-Ramadan [After-R]) were selected for spirometry measurements. Spirometry was performed around 5.5 to 3.5 h before sunset and the spirometric data were expressed as percentages of local spirometric norms. RESULTS: The two groups of fasters and non-fasters had similar ages and weights (13.35 ± 0.79 vs 12.96 ± 0.45 years, 46.8 ± 9.2 vs 41.7 ± 12.6 kg, respectively). There was no effect of Ramadan fasting on forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, peak expiratory flow, and maximal mid-expiratory flow. For example, during the Before-R, Mid-R, and After-R sessions, there was no significant difference between the fasters and non-fasters mean FVC (101 ± 11 vs 99 ± 14, 101 ± 12 vs 102 ± 14, 103 ± 11 vs 104 ± 13, respectively) or FEV1 (101 ± 13 vs 96 ± 16, 98 ± 11 vs 97 ± 16, 101 ± 10 vs 98 ± 16, respectively). CONCLUSIONS: Ramadan fasting had no interaction effect with the spirometric data of Tunisian healthy male adolescents.

Effects of cold water immersion on aerobic capacity and muscle strength of young footballers.

AIMS: The main aim was to compare aerobic performance data, determined before «period1¼ and after «period2¼ cold water immersion in two groups of footballers (CWI and no-CWI groups). METHODS: This is an experimental study with matching and randomization. The 20 male footballers, aged 17 to 20 years, were divided into two groups (n = 10 for each) following a random draw. The two groups were age-, height- and weight matched. 1000-m race was made during the two periods. Heart-rate (HR, % of theoretical maximum HR) and hemoglobin oxygen saturation (Oxy-sat, %) were measured before and after the race, and the time of the race (min) was noted. An Oxy-sat decrease > 4 points retained the diagnosis of exercise-induced desaturation. Eight CWI sessions (one per week), until the hip in a standing position (10 min; temperature: 11-12 °C) were performed. RESULTS: The two groups were age-, height- and weight matched. Comparatively to the race time of «period1¼, this of «period2¼ was decreased in the CWI group (3.21±0.04 vs. 3.15±0.04 min) and was increased in the no-CWI group (3.23±0.05 vs. 3.27±0.07 min). Comparatively to the HRs (before, after the race) of «period1¼, these of «period2¼ were decreased in the CWI group (36±1 vs. 34±1%; 56±3 vs. 44±2%) and were increased in the no-CWI group (35±2 vs. 36±1%; 55±2 vs. 57±2%). Comparatively to the after race Oxy-sat' of the «period1¼, this of «period2¼ was increased in the CWI group (96±1 vs. 98±0%) and was decreased in the no-CWI group (96±1 vs. 95±1%). While in the CWI group, the percent of desaturators was decreased between «period1¼ and «period2¼ (30 vs. 0%), in the no-CWI group, percentages remained similar (50 vs. 90%). CONCLUSION: CWI improves aerobic capacity and muscle strength of young footballers.

The Effects of Ramadan Intermittent Fasting (RIF) on Spirometric Data of Stable COPD Patients: A Pilot Study.

No previous study has raised the effects of RIF on lung function data of chronic obstructive pulmonary disease (COPD) patients. The objective of the present study was to assess the effects of RIF on spirometric data measured in male patients with a stable COPD. Sixteen patients with stable COPD (mean ± SD of age: 64 ± 7 years) who fasted during Ramadan volunteered to the study. Three sessions (Before-R, End-R, and After-R) were selected for spirometry tests that were consistently performed 2.5-4.5 hr before fasting break. Assessment sessions comprised: forced vital capacity (FVC), 1st s forced expiratory volume (FEV1), FEV1/FVC, peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), and forced expiratory flow rate at the x% of FVC to be exhaled (FEFx%). A reversibility test was performed only during the Before-Ramadan session. Spirometric data were expressed in percentages of local reference values. Findings were analyzed by applying repeated measures analysis of variance. The mean ± SD of the postbronchodilator FEV1/FVC ratio and the FEV1 were, respectively, 0.52 ± 0.14 and 48 ± 19%. The mean ± SD of FEV1 (Before-R: 47 ± 19, End-R: 45 ± 18, After-R: 44 ± 19%), FVC (Before-R: 73 ± 18, End-R: 71 ± 16, After-R: 69 ± 17%), FEV1/FVC (Before-R: 67 ± 16, End-R: 66 ± 16, After-R: 65 ± 16%), PEF (Before-R: 46 ± 19, End-R: 47 ± 22, After-R: 45 ± 21%), MMEF (Before-R: 19 ± 10, End-R: 18 ± 8, After-R: 18 ± 9%), FEF25% (Before-R: 16 ± 6, End-R: 16 ± 5, After-R: 15 ± 5%), FEF50% (Before-R: 21 ± 14, End-R: 20 ± 12, After-R: 20 ± 12%) and FEF75% (Before-R: 27 ± 19, End-R: 27 ± 19, After-R: 27 ± 19%) were not significantly influenced by RIF. RIF did not bring about any significant changes in the spirometric data of stable COPD male patients fasting the 2016 holy month of Ramadan.

The Effects of Ramadan Fasting on the Spirometric Data of Healthy Adult Males.

The few studies carried out on the effects of Ramadan fasting (RF) on spirometric values present contradictory conclusions. This study aimed at assessing whether RF affects healthy adults' spirometric values. Twenty-nine nonsmoking healthy males ( M ± standard error of mean [ SEM] of age: 27 ± 1 years) who fasted during Ramadan (June 29-July 28, 2014) volunteered to the study. Three periods (before-Ramadan [June 23-25], mid-Ramadan [July 14-16] and after-Ramadan [August 11-14]) were selected for spirometry measurements that were consistently performed 5.5 to 3.5 hours (between 15:00 and 17:00 hours) before fasting break. Assessment sessions comprised following: weight (kg), forced vital capacity (FVC), first second expiratory volume (FEV1), FEV1/FVC, peak expiratory flow (PEF), maximal mid expiratory flow (MMEF), and forced expiratory flow rate at the x% of FVC to be exhaled (FEF x%). Spirometric data were expressed in percentages of reference values. Results were analyzed by applying repeated measures analysis of variance. The M ± SEM of weight (before-R: 81.6 ± 2.8 kg, mid-R: 80.8 ± 2.9 kg, after-R: 81.2 ± 2.9 kg), FEV1 (before-R: 99 ± 2%, mid-R: 98 ± 2%, after-R: 98 ± 2%), FVC (before-R: 103 ± 2%, mid-R: 101 ± 2%, after-R: 101 ± 2%), PEF (before-R: 112 ± 3%, mid-R: 113 ± 2%, after-R: 114 ± 3%), MMEF (before-R: 83 ± 3%, mid-R: 83 ± 3%, after-R: 82 ± 3%), FEF25% (before-R: 90 ± 5%, mid-R: 89 ± 6%, after-R: 87 ± 6%), FEF50% (before-R: 94 ± 4%, mid-R: 91 ± 4%, after-R: 93 ± 3%), and FEF75% (before-R: 108 ± 3%, mid-R: 111 ± 2%, after-R:111 ± 3%) were not significantly influenced by RF. To conclude, RF did not bring about any significant changes in the spirometric values of nonsmoking healthy adult males.

Effects of one-night sleep deprivation on selective attention and isometric force in adolescent karate athletes.

BACKGROUND: Most of the available literature related to aspects of sleep deprivation is primarily focused on memory and learning, and studies regarding its effects on selective attention and/or physical performance are scarce. Moreover, the available literature includes general population or people involved in team sports (e.g. volleyball). However, only few studies were performed on athletes involved in combat sports (e.g. karate). The aim of the present study was to determine the effects of a total one-night sleep deprivation (1NSD) on activation and inhibition processes of selective attention and on maximal isometric force in karate athletes. METHODS: Twelve young karate athletes (mean age 16.9±0.8 years) were enrolled. The protocol consists of two successive sessions: a normal night's sleep (NNS) and a total 1NSD. After each night, athletes performed selective attention and muscle strength tests during the same following three times (T) of the day: T1NNS or T11NSD: 8-9 a.m.; T2NNS or T21NSD: 12 a.m.-1 p.m.; T3NNS or T31NSD: 4-5 p.m. Activation (simple [SRT] and choice reaction times [CRT]) and inhibition (negative priming) processes were evaluated using Superlab v. 4.5 software (Cedrus Corporation, San Pedro, CA, USA). Maximal force and maximal force time (MFT) of brachial biceps isometric contraction were evaluated (Ergo System®, Globus, Codognè, Italy). A non-parametric test was used to evaluate the sessions (NNS vs. SND for the same time period) and time (T1NNS vs. 1NSD) effects. RESULTS: All athletes completed all tests after a NNS. Twelve, eleven and four athletes completed all tests at T11NSD, T21NSD and T31NSD, respectively. As for sessions effects, no statistically significant difference was found. As for time effects, a significant increase in SRT at T21NSD vs. T1NNS (345±47 vs. 317±33 ms, respectively), a significant increase in MFT at T21NSD vs. T1NNS (2172±260 vs.1885±292 ms, respectively), and no significant changes in CRT and negative priming reaction time or MFT data were observed. CONCLUSIONS: 1NSD affects both activation processes of selective attention and maximal isometric strength, two key skills in combat sports.

6-min walk-distance norms in adults Arab populations: a literature review.

INTRODUCTION: The primary outcome of the 6-min walk-test is the 6-min walk-distance (6MWD). Its interpretation relies upon the comparison of the measured 6MWD with the predicted one from published norms. OBJECTIVE: The aim of the present review is to report the 6MWD norms published for healthy adults Arab populations. METHODS: The review includes a literature search, from 1970 to January 5th 2017 using the PubMed search engine. Reference equations lists of retrieved English/French articles were searched for any supplementary references. The research includes the combination of the following (or their synonyms) "Medical Subject Headings" or "Title/Abstract" terms: «walking¼ AND «reference values¼ AND «Arabs¼. RESULTS: Five studies, conducted in Saudi-Arabia (n=2), Tunisia (n=2) and Algeria (n=1) were included. Norms comprised the following factors: age (Yrs), height (cm), weight (kg), body mass index (BMI, kg/m2), sex (0:women; 1:men) and physical activity level. Five norms were proposed for Tunisian aged 40-79 years [6MWD (m) = 299.8 - 4.34xAge + 3.43xHeight - 1.46xWeight + 62.5xSex] or aged 40-85 years [6MWD (m) = 720.50 + 160.27xSex - 5.14xAge - 2.23xWeight + 2.72xHeight], for Saudi-Arabian aged 16-50 years [6MWD (m) = - 28.5 + 2.81xHeight + 0.79xAge] or aged 18-71 years [6MWD (m) = 342.650 + 74.31xPhysical activity level + 33.88xSex - 4.25xAge] and for Algerian aged 16-40 years [6MWD (m) = 800.05 + 64.71xSex - 10.23xBMI - 1.63xAge + 2.05xWeight]. These norms explained 25% to 77% of the 6MWD variability. CONCLUSION: Fewer 6MWD norms exist for adults' Arab population. Other norms are welcome.

Effects of Ramadan intermittent fasting on North African children's heart rate and oxy-haemoglobin saturation at rest and during sub-maximal exercise.

AIM: To examine the effects of Ramadan intermittent fasting (RIF) on the heart rate (HR) and oxyhaemoglobin saturation levels (oxy-sat) of boys at rest and during a six-minute walking test (6MWT). METHODS: Eighteen boys (age: 11.9 ± 0.8 years, height: 153.00 ± 8.93 cm, body mass: 55.4 ± 18.2 kg), who fasted the entire month of Ramadan in 2012 for the first time in their lives, were included. The experimental protocol comprised four testing phases: two weeks before Ramadan (pre-R), the end of the second week of Ramadan (R-2), the end of the fourth week of Ramadan (R-4), and 10 to 12 days after the end of Ramadan (post-R). During each phase, participants performed the 6MWT at approximately 15:00. HR (expressed as percentage of maximal predicted HR) and oxy-sat (%) were determined at rest and in each minute of the 6MWT. RESULTS: R-4 HR values were lower than those of (1) pre-R (in the second minute), (2) R-2 (in the first and second minutes), and (3) post-R (in the first, second, fourth, fifth and sixth minutes). R-2 oxy-sat values were higher than those of pre-R (in the third minute) and those of post-R (in the fifth minute). Post-R oxy-sat values were lower than those of pre-R and R-4 in the fifth minute. These oxy-sat changes were not clinically significant since the difference was less than five points. CONCLUSION: In non-athletic children, their first RIF influenced their heart rate data but had a minimal effect on oxy-sat values.

Influencing factors of the 6-min walk distance in adult Arab populations: a literature review.

Background Walk tests, especially the 6-min walk-test (6MWT), are commonly used in order to evaluate submaximal exercise capacity. The primary outcome of the 6MWT is the 6-min walk-distance (6MWD). Numerous demographic, physiological and anthropometric factors can influence the 6MWD in healthy adults. Objective The purpose of the present review is to highlight and discuss the 6MWD influencing factors in healthy of the healthy adult Arab populations. Methods It is a review including a literature search, from 1970 to September 31th 2015 using the PubMed, the Science Direct databases and the World Wide Web on Google search engine. Reference lists of retrieved English/French articles were searched for any additional references. Results Six studies, conducted in Tunisia (n=2), Saudi Arabia (n=3) and Algeria (n=1) were included. All studies were conducted according to the 2002-American-thoracic-society guidelines for the 6MWT. In addition to anthropometric data (sex, age, height, weight, body mass index, lean mass), the following data were recognized as 6MWD influencing factors: schooling and socioeconomic levels, urban origin, parity, physical activity score or status, metabolic equivalent task for moderate activity, spirometric data, end-walk heart-rate, resting diastolic blood pressure, dyspnoea Borg value and niqab-wearing. Conclusion The 6MWD influencing factors in adult Arab populations are numerous and include some specific predictors such as parity, physical activity level and niqab-wearing.

Ramadan fasting does not adversely affect neuromuscular performances and reaction times in trained karate athletes.

BACKGROUND: The present study aimed to investigate the concomitant effects of Ramadan intermittent fast (RIF) and muscle fatigue on neuromuscular performances and reaction times in young trained athletes. METHODS: Eight karate players (17.2 ± 0.5 years) were tested on three sessions: during a control period (S1: one week before Ramadan), and during the first (S2) and the fourth week of RIF (S3). Dietary intake and anthropometric measurements were assessed before each session. During each test session, participants performed maximal voluntary isometric contractions (MVC) and a submaximal contraction at 75 % MVC until exhaustion (T lim ) of the right elbow flexors. Surface electromyography was recorded from biceps brachii muscle during MVC and T lim . Simple (SRT) and choice (CRT) reaction times were evaluated at rest and just after T lim in a random order. RESULTS: The total daily energy (S2: +19.5 %, p < 0.05; S3: +27.4 %, p < 0.01) and water (S2: +26.8 %, p < 0.01; S3: +23.2 %, p < 0.05) intake were significantly increased during RIF. However, neither body mass nor body mass index was altered by RIF (F (2,14) = 0.80, p = 0.47 and F (2,14) = 0.78, p = 0.48, respectively). In addition, T lim (F (2,14) = 2.53, p = 0.12), MVC (F (2,14) = 0.51, p = 0.61) and associated electrical activity (F (2,14) = 0.13, p = 0.88) as well as neuromuscular efficiency (F (2,14) = 0.27, p = 0.76) were maintained during RIF. Moreover, neither SRT nor CRT was affected by RIF (F (2,14) = 1.82, p = 0.19 and F (2,14) = 0.26, p = 0.78, respectively) or neuromuscular fatigue (F (1,7) = 0.0002, p = 0.98 and F (1,7) = 3.78, p = 0.09, respectively). CONCLUSIONS: The present results showed that RIF did not adversely affect the neuromuscular performances and anthropometric parameters of elite karate athletes who were undertaking their usual training schedule. In addition, neither RIF nor neuromuscular fatigue poorly affects reaction times in elite karate athletes.