{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:18:52Z","timestamp":1760059132550,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,5,24]],"date-time":"2025-05-24T00:00:00Z","timestamp":1748044800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Mitacs Accelerate doctoral fellowship","award":["IT28971","66"],"award-info":[{"award-number":["IT28971","66"]}]},{"name":"Swimming Natation Canada and Institut national du sport du Qu\u00e9bec","award":["IT28971","66"],"award-info":[{"award-number":["IT28971","66"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Wearable technology can nowadays be used to improve para-swimming coaching; however, the extent to which individual anatomy affects features of swimming variability is unclear. Six paralympic swimmers were recruited, their upper-limb segment lengths were measured, and their absolute bilateral limb asymmetry indices (AbsLAIUL) were calculated. They were instrumented with a sacrum-worn inertial measurement unit and performed an in-water, fatiguing, freestyle aerobic test at incrementally faster paces. Stroke-to-stroke outcome and execution variability were calculated, respectively, using sample entropy (SampEn) and fractal dimension (FD) on forward and mediolateral linear acceleration signals. Significantly increased perceived exertion scores (F(4,28) = 154.1, p &lt; 0.001) were observed. Execution and outcome variability increased in the forward (SampEn = F(4,25) = 11.86, p &lt; 0.001; FD = F(4,24) = 6.17, p = 0.001) and mediolateral (SampEn = F(4,25) = 9.46, p &lt; 0.001; FD = F(4,24) = 27.64, p &lt; 0.001) directions. Modelling of FD (only) improved with AbsLAIUL as a covariate (forward = F(1,24) = 9.68, p = 0.005; mediolateral = F(1,24) = 8.57, p = 0.021), suggesting that AbsLAIUL affects only execution, but not outcome, variability. This information could help coaches determine which coordination indices should be personalized when monitoring variability during para-swimming training.<\/jats:p>","DOI":"10.3390\/s25113297","type":"journal-article","created":{"date-parts":[[2025,5,25]],"date-time":"2025-05-25T20:26:50Z","timestamp":1748204810000},"page":"3297","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Measuring the Impact of Limb Asymmetry on Movement Irregularity and Complexity Changes During an Incremental Step Test in Para-Swimmers Using Inertial Measurement Units"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7134-6023","authenticated-orcid":false,"given":"Matthew","family":"Slopecki","sequence":"first","affiliation":[{"name":"Department of Kinesiology and Physical Education, McGill University, Montreal, QC H2W 1S4, Canada"},{"name":"Institut National du Sport, Montreal, QC H1V 3N7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8212-3482","authenticated-orcid":false,"given":"Julien","family":"Cl\u00e9ment","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Physical Education, McGill University, Montreal, QC H2W 1S4, Canada"},{"name":"Institut National du Sport, Montreal, QC H1V 3N7, Canada"},{"name":"D\u00e9partement de G\u00e9nie des Syst\u00e8mes, \u00c9cole de Technologie Sup\u00e9rieure, Montr\u00e9al, QC H3C 1K3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mathieu","family":"Charbonneau","sequence":"additional","affiliation":[{"name":"Institut National du Sport, Montreal, QC H1V 3N7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6155-8946","authenticated-orcid":false,"given":"Julie N.","family":"C\u00f4t\u00e9","sequence":"additional","affiliation":[{"name":"Department of Kinesiology and Physical Education, McGill University, Montreal, QC H2W 1S4, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1097\/01.NPT.0000281949.48193.d9","article-title":"Optimal Movement Variability","volume":"30","author":"Stergiou","year":"2006","journal-title":"J. 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