{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T06:07:50Z","timestamp":1770530870419,"version":"3.49.0"},"reference-count":58,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2023,3,22]],"date-time":"2023-03-22T00:00:00Z","timestamp":1679443200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fukuoka University Institute for Physical activity","award":["No.926"],"award-info":[{"award-number":["No.926"]}]},{"name":"Fukuoka University Institute for Physical activity","award":["No.K22011"],"award-info":[{"award-number":["No.K22011"]}]},{"name":"Fukuoka University Institute for Physical activity","award":["No.190712"],"award-info":[{"award-number":["No.190712"]}]},{"name":"Asahi Kasei Corp","award":["No.926"],"award-info":[{"award-number":["No.926"]}]},{"name":"Asahi Kasei Corp","award":["No.K22011"],"award-info":[{"award-number":["No.K22011"]}]},{"name":"Asahi Kasei Corp","award":["No.190712"],"award-info":[{"award-number":["No.190712"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Ultra-short-term heart rate variability (HRV) has been validated in the resting state, but its validity during exercise is unclear. This study aimed to examine the validity in ultra-short-term HRV during exercise considering the different exercise intensities. HRVs of twenty-nine healthy adults were measured during incremental cycle exercise tests. HRV parameters (Time-, frequency-domain and non-linear) corresponding to each of the 20% (low), 50% (moderate), and 80% (high) peak oxygen uptakes were compared between the different time segments of HRV analysis (180 s (sec) segment vs. 30, 60, 90, and 120-sec segments). Overall, the differences (bias) between ultra-short-term HRVs increased as the time segment became shorter. In moderate- and high-intensity exercises, the differences in ultra-short-term HRV were more significant than in low intensity exercise. Thus, we discovered that the validity of ultra-short-term HRV differed with the duration of the time segment and exercise intensities. However, the ultra-short-term HRV is feasible in the cycling exercise, and we determined some optimal time duration for HRV analysis for across exercise intensities during the incremental cycling exercise.<\/jats:p>","DOI":"10.3390\/s23063325","type":"journal-article","created":{"date-parts":[[2023,3,22]],"date-time":"2023-03-22T06:35:28Z","timestamp":1679466928000},"page":"3325","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["The Validity of Ultra-Short-Term Heart Rate Variability during Cycling Exercise"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4009-8439","authenticated-orcid":false,"given":"Yukiya","family":"Tanoue","sequence":"first","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Ritsumeikan-Global Innovation Research Organization, Ritsumeikan University, Kusatsu 525-8577, Japan"},{"name":"Institute of Advanced Research for Sport and Health Science, Research Organization of Science and Technology, Ritsumeikan University, Kusatsu 525-8577, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shihoko","family":"Nakashima","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9759-5121","authenticated-orcid":false,"given":"Tomohiro","family":"Komatsu","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Center for Preventive, Anti-Aging, and Regenerative Medicine, Fukuoka University Hospital, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miki","family":"Kosugi","sequence":"additional","affiliation":[{"name":"Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Saki","family":"Kawakami","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1334-1918","authenticated-orcid":false,"given":"Shotaro","family":"Kawakami","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4978-1592","authenticated-orcid":false,"given":"Ryoma","family":"Michishita","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yasuki","family":"Higaki","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6075-7329","authenticated-orcid":false,"given":"Yoshinari","family":"Uehara","sequence":"additional","affiliation":[{"name":"Institute for Physical Activity, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan"},{"name":"Center for Preventive, Anti-Aging, and Regenerative Medicine, Fukuoka University Hospital, Fukuoka 814-0180, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"258","DOI":"10.3389\/fpubh.2017.00258","article-title":"An Overview of Heart Rate Variability Metrics and Norms","volume":"5","author":"Shaffer","year":"2017","journal-title":"Front. 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