{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T01:36:30Z","timestamp":1787016990665,"version":"build-2736575974"},"reference-count":40,"publisher":"BMJ","issue":"3","license":[{"start":{"date-parts":[[2025,9,9]],"date-time":"2025-09-09T00:00:00Z","timestamp":1757376000000},"content-version":"unspecified","delay-in-days":70,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"IF Elfsborg","award":["50 000 Sek"],"award-info":[{"award-number":["50 000 Sek"]}]},{"name":"Folksam research council","award":["50 000 sek"],"award-info":[{"award-number":["50 000 sek"]}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open Sport Exerc Med"],"accepted":{"date-parts":[[2025,8,21]]},"published-print":{"date-parts":[[2025,7]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>Hamstring strain injury (HSI) is the most common time-loss injury in football and is prone to recurrence. This exploratory study aimed to describe the relationship between short-term external training load (TL) and HSI occurrence in male senior football players at the professional level.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>TL data in terms of global positioning system (GPS) variables and HSI incidence were collected over four seasons from 25 senior professional football players. GPS variables included total distance (TD), very intense accelerations (&gt;3.00 m\/s\u00b2), very intense decelerations (&lt;\u20133.00 m\/s\u00b2), high-speed running distance (&gt;19.8\u2009km\/hour), maximal sprint distance (&gt;29.8\u2009km\/hour) and maximal velocity. For each injury case, TL during the 7 and 14 days preceding the injury was compared with matched control periods from the same player.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>25 hamstring injuries were included for analysis. Large interindividual variation in TL patterns was observed, with some players exhibiting higher and others lower TL in the periods preceding injury compared with control periods. No consistent group-level trends were identified between injured and control periods.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>This exploratory study found considerable individual variability in TL prior to HSI and no clear group-level patterns. These findings suggest that short-term TL metrics alone may have limited utility in predicting HSI risk at the group level in professional football players.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjsem-2025-002649","type":"journal-article","created":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T04:40:19Z","timestamp":1757479219000},"page":"e002649","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":3,"title":["Hamstring injury risk in male professional football: do external training loads play a role?"],"prefix":"10.1136","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-2715-3133","authenticated-orcid":false,"given":"Tania","family":"Nilsson","sequence":"first","affiliation":[{"name":"Department of Food and Nutrition and Sports Science, University of Gothenburg, Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dan","family":"Fransson","sequence":"additional","affiliation":[{"name":"Department of Food and Nutrition and Sports Science, University of Gothenburg, Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8786-0438","authenticated-orcid":false,"given":"Mats","family":"Borjesson","sequence":"additional","affiliation":[{"name":"Department of Molecular and Clinical Medicine, University of Gothenburg Sahlgrenska Academy, Goteborg, Sweden"},{"name":"Department of Medicine, Geriatrics and Acute Medicine \u00d6stra Sjukhuset, Gothenburg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Matilda","family":"Lundblad","sequence":"additional","affiliation":[{"name":"Department of Food and Nutrition and Sports Science, University of Gothenburg, Gothenburg, Sweden"},{"name":"Department of Orthopaedics, Sahlgrenska Academy, Goteborg, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Ivarsson","sequence":"additional","affiliation":[{"name":"Centre of Research on Welfare, Health and Sport, Halmstad University, Halmstad, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2025,9,9]]},"reference":[{"key":"2025090921401391000_11.3.e002649.1","doi-asserted-by":"publisher","DOI":"10.1136\/bjsm.2009.060582"},{"key":"2025090921401391000_11.3.e002649.2","doi-asserted-by":"crossref","first-page":"292","DOI":"10.1136\/bjsports-2021-105407","article-title":"Hamstring injury rates have increased during recent seasons and now constitute 24% of all injuries in men\u2019s professional football: the UEFA Elite Club Injury Study from 2001\/02 to 2021\/22","volume":"57","author":"Ekstrand","year":"2022","journal-title":"Br J Sports Med"},{"key":"2025090921401391000_11.3.e002649.3","doi-asserted-by":"crossref","DOI":"10.1136\/bmjsem-2019-000675","article-title":"Estimation of injury costs: financial damage of English Premier League teams\u2019 underachievement due to injuries","volume":"6","author":"Eliakim","year":"2020","journal-title":"BMJ Open Sport Exerc Med"},{"key":"2025090921401391000_11.3.e002649.4","doi-asserted-by":"publisher","DOI":"10.1136\/bjsm.2002.002352"},{"key":"2025090921401391000_11.3.e002649.5","doi-asserted-by":"crossref","DOI":"10.1136\/bmjsem-2022-001461","article-title":"Risk factors for hamstring muscle injury in male elite football: medical expert experience and conclusions from 15 European Champions League clubs","volume":"9","author":"Ekstrand","year":"2023","journal-title":"BMJ Open Sport Exerc Med"},{"key":"2025090921401391000_11.3.e002649.6","doi-asserted-by":"publisher","DOI":"10.1136\/bjsports-2019-100983"},{"key":"2025090921401391000_11.3.e002649.7","doi-asserted-by":"publisher","DOI":"10.1136\/bjsports-2021-104769"},{"key":"2025090921401391000_11.3.e002649.8","doi-asserted-by":"publisher","DOI":"10.1007\/s40279-023-01925-x"},{"key":"2025090921401391000_11.3.e002649.9","doi-asserted-by":"crossref","first-page":"1057","DOI":"10.5114\/biolsport.2023.125595","article-title":"Exposures to near-to-maximal speed running bouts during different turnarounds in elite football: association with match hamstring injuries","volume":"40","author":"Buchheit","year":"2023","journal-title":"Biol Sport"},{"key":"2025090921401391000_11.3.e002649.10","doi-asserted-by":"crossref","DOI":"10.3390\/sports8050065","article-title":"Mechanisms of Hamstring Strain Injury: Interactions between Fatigue, Muscle Activation and Function","volume":"8","author":"Huygaerts","year":"2020","journal-title":"Sports (Basel)"},{"key":"2025090921401391000_11.3.e002649.11","doi-asserted-by":"publisher","DOI":"10.1097\/JSM.0000000000001109"},{"key":"2025090921401391000_11.3.e002649.12","doi-asserted-by":"crossref","first-page":"779","DOI":"10.1177\/17479541231164507","article-title":"Running more than before? 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