Biology of Sport
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Changes in physical fitness and body composition of athletes after the COVID-19 lockdown: a systematic review, meta-analysis, and meta-regression, with assessment of the certainty of evidence

Jad Adrian Washif
1
,
Khaled Trabelsi
2, 3
,
Jeffrey Pagaduan
4
,
Marie Stella Louise Perreras
5
,
Imen Moussa-Chamari
6
,
Narimen Yousfi
7, 8
,
David B. Pyne
9
,
Karim Chamari
10, 11

  1. High Performance Branch, Sports Performance Division, National Sports Institute of Malaysia, Kuala Lumpur, Malaysia
  2. High Institute of Sport and Physical Education of Sfax, University of Sfax, Sfax, Tunisia
  3. Department of Movement Sciences and Sports Training, School of Sport Science, The University of Jordan, Amman, Jordan
  4. Melbourne School of Psychological Sciences, The University of Melbourne, Melbourne, Victoria, Australia
  5. Department of Sports Medicine and Science Graduate School, Konkuk University, Seoul, Republic of Korea
  6. Sport Coaching Department; College of Sport Sciences, Qatar University, Doha, Qatar
  7. Research Unit “Sport Sciences, Health and Movement”, Higher Institute of Sports and Physical Education of Kef, University of Jendouba, Kef, Tunisia
  8. Tunisian Research Laboratory “Sport Performance Optimisation”, National Center of Medicine and Science in Sport, Tunis, Tunisia
  9. Research Institute for Sport and Exercise, University of Canberra, Canberra, Australia
  10. Research Office, Naufar, Wellness and Recovery Center, Doha, Qatar
  11. Higher institute of Sport and Physical Education, ISSEP Ksar Saïd, Manouba University, Tunis, Tunisia
Biol Sport. 2026;43:463–488
DOI: https://doi.org/10.5114/biolsport.2026.153307
Online publish date: 2025/10/01
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