Publications by authors named "Karim Khalladi"

Healthy adult Muslims who practice Ramadan fasting (RF) follow strict religious rules regarding their lifestyle. RF influences several parameters, including nutrition, hydration, and sleep habits, and can potentially reduce physical performance. It seems that RF prevents athletes from training and participating in competitions, and prevents the general community from engaging in physical exercise.

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Purpose: To investigate differences in athletes' knowledge, beliefs, and training practices during COVID-19 lockdowns with reference to sport classification and sex. This work extends an initial descriptive evaluation focusing on athlete classification.

Methods: Athletes (12,526; 66% male; 142 countries) completed an online survey (May-July 2020) assessing knowledge, beliefs, and practices toward training.

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Objective: Disrupted sleep and training behaviors in athletes have been reported during the COVID-19 pandemic. We aimed at investigating the combined effects of Ramadan observance and COVID-19 related lockdown in Muslim athletes.

Methods: From an international sample of athletes ( = 3,911), 1,681 Muslim athletes (from 44 countries; 25.

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Article Synopsis
  • The study examined how the length of COVID-19 lockdown and training intensity affected sleep quality and insomnia symptoms in 1,454 elite athletes from various countries, using a web-based questionnaire.
  • Results showed that sleep quality (measured by PSQI) and insomnia severity (measured by ISI) worsened during the lockdown, particularly for those who reduced their training intensity, with significant increases in PSQI and ISI scores.
  • While the duration of the lockdown did not significantly impact sleep quality, athletes who were locked down for more than 2 months reported greater insomnia severity compared to those who were confined for less than 1 month.
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Objective: In a convenience sample of athletes, we conducted a survey of COVID-19-mediated lockdown (termed 'lockdown' from this point forward) effects on: (i) circadian rhythms; (ii) sleep; (iii) eating; and (iv) training behaviors.

Methods: In total, 3911 athletes [mean age: 25.1 (range 18-61) years, 1764 female (45%), 2427 team-sport (63%) and 1442 elite (37%) athletes] from 49 countries completed a multilingual cross-sectional survey including the Pittsburgh Sleep Quality Index and Insomnia Severity Index questionnaires, alongside bespoke questions about napping, training, and nutrition behaviors.

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Objective: Our objective was to explore the training-related knowledge, beliefs, and practices of athletes and the influence of lockdowns in response to the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods: Athletes (n = 12,526, comprising 13% world class, 21% international, 36% national, 24% state, and 6% recreational) completed an online survey that was available from 17 May to 5 July 2020 and explored their training behaviors (training knowledge, beliefs/attitudes, and practices), including specific questions on their training intensity, frequency, and session duration before and during lockdown (March-June 2020).

Results: Overall, 85% of athletes wanted to "maintain training," and 79% disagreed with the statement that it is "okay to not train during lockdown," with a greater prevalence for both in higher-level athletes.

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This study aimed to determine if sleep quality and psychological factors were associated with time to meet the discharge criteria to return to sport (RTS) following anterior cruciate ligament reconstruction (ACL-R) among athletes. A cohort-study design included 89 athletes following ACL-R. Each participant completed a battery of questionnaires at 6 different time points: within 3 days of injury occurrence and at post-surgery (1.

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Objective: Insufficient sleep duration and quality has negative effects on athletic performance, injury susceptibility and athlete development. This study aimed to assess the sleep characteristics of professional Qatar Stars League (QSL) soccer players.

Methods: In a cross-sectional study, QSL players (n=111; 23.

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Chronotype questionnaires provide a simple and time-effective approach to assessing individual differences in circadian variations. Chronotype questionnaires traditionally focused on one dimension of chronotype, namely its orientation along a continuum of morningness and eveningness. The Caen Chronotype Questionnaire (CCQ) was developed to assess an additional dimension of chronotype that captures the extent to which individual functioning varies during the day (amplitude).

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