{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T01:57:00Z","timestamp":1772848620542,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,1,24]],"date-time":"2019-01-24T00:00:00Z","timestamp":1548288000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sports"],"abstract":"<jats:p>The assessment of oxygen uptake (VO2) kinetics is a valuable non-invasive way to evaluate cardiorespiratory and metabolic response to exercise. The aim of the study was to develop, describe and evaluate an online VO2 fitting tool (VO2FITTING) for dynamically editing, processing, filtering and modelling VO2 responses to exercise. VO2FITTING was developed in Shiny, a web application framework for R language. Validation VO2 datasets with both noisy and non-noisy data were developed and applied to widely-used models (n = 7) for describing different intensity transitions to verify concurrent validity. Subsequently, we then conducted an experiment with age-group swimmers as an example, illustrating how VO2FITTING can be used to model VO2 kinetics. Perfect fits were observed, and parameter estimates perfectly matched the known inputted values for all available models (standard error = 0; p &lt; 0.001). The VO2FITTING is a valid, free and open-source software for characterizing VO2 kinetics in exercise, which was developed to help the research and performance analysis communities.<\/jats:p>","DOI":"10.3390\/sports7020031","type":"journal-article","created":{"date-parts":[[2019,1,24]],"date-time":"2019-01-24T11:12:48Z","timestamp":1548328368000},"page":"31","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["VO2FITTING: A Free and Open-Source Software for Modelling Oxygen Uptake Kinetics in Swimming and other Exercise Modalities"],"prefix":"10.3390","volume":"7","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0494-0000","authenticated-orcid":false,"given":"Rodrigo","family":"Zacca","sequence":"first","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, Porto 4200-450, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP), University of Porto, Porto 4200-450, Portugal"},{"name":"CAPES Foundation, Ministry of Education of Brazil, Bras\u00edlia 70040-031, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8904-002X","authenticated-orcid":false,"given":"Rui","family":"Azevedo","sequence":"additional","affiliation":[{"name":"CESPU, Institute of Research and Advanced Training in Health Sciences and Technologies (IINFACTS), Gandra PRD 4585-116, Portugal"}]},{"given":"Pedro","family":"Figueiredo","sequence":"additional","affiliation":[{"name":"Portugal Football School, Portuguese Football Federation, Cruz Quebrada-Dafundo 1495-433, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4109-2939","authenticated-orcid":false,"given":"Jo\u00e3o Paulo","family":"Vilas-Boas","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, Porto 4200-450, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP), University of Porto, Porto 4200-450, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0848-8226","authenticated-orcid":false,"given":"Fl\u00e1vio A. de S.","family":"Castro","sequence":"additional","affiliation":[{"name":"Aquatic Sports Research Group, Universidade Federal do Rio Grande do Sul, Porto Alegre 90690-200, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1555-5079","authenticated-orcid":false,"given":"David B.","family":"Pyne","sequence":"additional","affiliation":[{"name":"Research Institute for Sport and Exercise, University of Canberra, Canberra, ACT 2617, Australia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5811-0443","authenticated-orcid":false,"given":"Ricardo J.","family":"Fernandes","sequence":"additional","affiliation":[{"name":"Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, Porto 4200-450, Portugal"},{"name":"Porto Biomechanics Laboratory (LABIOMEP), University of Porto, Porto 4200-450, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,1,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"538","DOI":"10.1123\/ijspp.2018-0093","article-title":"An Integrated, Multifactorial Approach to Periodization for Optimal Performance in Individual and Team Sports","volume":"13","author":"Mujika","year":"2018","journal-title":"Int. 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