{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:40:33Z","timestamp":1760236833482,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,29]],"date-time":"2021-12-29T00:00:00Z","timestamp":1640736000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Italian Ministry of University and Research","award":["7101\/01\u2013E.F.2020"],"award-info":[{"award-number":["7101\/01\u2013E.F.2020"]}]},{"name":"Italian Ministry of Health","award":["RC2020","AF2018"],"award-info":[{"award-number":["RC2020","AF2018"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study proposes the instrumental analysis of the physiological and biomechanical adaptation of football players to a fatigue protocol during the month immediately after the COVID-19 lockdown, to get insights into fitness recovery. Eight male semi-professional football players took part in the study and filled a questionnaire about their activity during the lockdown. At the resumption of activities, the mean heart rate and covered distances during fatiguing exercises, the normalized variations of mean and maximum exerted power in the Wingate test and the Bosco test outcomes (i.e., maximum height, mean exerted power, relative strength index, leg stiffness, contact time, and flight time) were measured for one month. Questionnaires confirmed a light-intensity self-administered physical activity. A significant effect of fatigue (Wilcoxon signed-rank test p &lt; 0.05) on measured variables was confirmed for the four weeks. The analysis of the normalized variations of the aforementioned parameters allowed the distinguishing of two behaviors: downfall in the first two weeks, and recovery in the last two weeks. Instrumental results suggest a physiological and ballistic (i.e., Bosco test outcomes) recovery after four weeks. As concerns the explosive skills, the observational data are insufficient to show complete recovery.<\/jats:p>","DOI":"10.3390\/s22010242","type":"journal-article","created":{"date-parts":[[2021,12,29]],"date-time":"2021-12-29T23:31:35Z","timestamp":1640820695000},"page":"242","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Quantitative Analysis of Performance Recovery in Semi-Professional Football Players after the COVID-19 Forced Rest Period"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2943-7690","authenticated-orcid":false,"given":"Luigi","family":"Truppa","sequence":"first","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"Department of Excellence in Robotics & AI, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"},{"name":"IRCCS Fondazione don Carlo Gnocchi, 50143 Firenze, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lorenzo","family":"Nuti","sequence":"additional","affiliation":[{"name":"School of Biomedical Engineering, Universit\u00e0 di Pisa, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefano","family":"Mazzoleni","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Information Technology, Politecnico di Bari, 70125 Bari, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pietro","family":"Garofalo","sequence":"additional","affiliation":[{"name":"Turingsense EU Lab s.r.l., 47121 Forli, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0760-052X","authenticated-orcid":false,"given":"Andrea","family":"Mannini","sequence":"additional","affiliation":[{"name":"IRCCS Fondazione don Carlo Gnocchi, 50143 Firenze, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,29]]},"reference":[{"doi-asserted-by":"crossref","unstructured":"Paoli, A., and Musumeci, G. 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