{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T19:59:19Z","timestamp":1777406359395,"version":"3.51.4"},"reference-count":46,"publisher":"PeerJ","license":[{"start":{"date-parts":[[2023,6,20]],"date-time":"2023-06-20T00:00:00Z","timestamp":1687219200000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:sec>\n               <jats:title>Background<\/jats:title>\n               <jats:p>Repeat power ability (RPA) assessments are a valuable evaluation of an athlete\u2019s ability to repeatedly perform high intensity movements. Establishing the most reliable and valid loaded jump RPA assessment and method to quantify RPA has yet to be determined. This study aimed to compare the reliability and validity of an RPA assessment performed with loaded squat jumps (SJ) or countermovement jumps (CMJ) using force-time derived mean and peak power output.<\/jats:p>\n            <\/jats:sec>\n            <jats:sec>\n               <jats:title>Materials and Methods<\/jats:title>\n               <jats:p>RPA was quantified using calculations of average power output, a fatigue index and a percent decrement score for all repetitions and with the first and last repetitions removed. Validity was established by comparing to a 30 second Bosco repeated jump test (30BJT). Eleven well-trained male field hockey players performed one set of 20 repetitions of both SJs (20SJ) and CMJs (20CMJ) on separate occasions using a 30% one repetition maximum half squat load. These assessments were repeated 7 days apart to establish inter-test reliability. On a separate occasion, each participant performed the 30BJT.<\/jats:p>\n            <\/jats:sec>\n            <jats:sec>\n               <jats:title>Results<\/jats:title>\n               <jats:p>The reliability of average peak power for 20SJ and 20CMJ was acceptable (CV &lt; 5%; ICC &gt; 0.9), while average mean power reliability for 20CMJ (CV &lt; 5%; ICC &gt; 0.9) was better than 20SJ (CV &gt; 5%; ICC &gt; 0.8). Percent decrement of 20CMJ peak power, with the first and final jump removed from the percent decrement calculation (PD%CMJ<jats:sub>peak18<\/jats:sub>), was the most reliable measurement of power output decline (CV &lt; 5 %; ICC &gt; 0.8). Average mean and peak power for both RPA protocols had moderate to strong correlations with 30BJT average mean and peak power (r = 0.5\u20130.8; <jats:italic>p<\/jats:italic>&lt; 0.05\u20130.01). No RPA measurements of power decline were significantly related to BJT measurements of power decline.<\/jats:p>\n            <\/jats:sec>\n            <jats:sec>\n               <jats:title>Conclusions<\/jats:title>\n               <jats:p>These findings indicate that PD%CMJ<jats:sub>peak18<\/jats:sub> is the most reliable measure of RPA power decline. The lack of relationship between power decline in the loaded RPA and the 30BJT assessment suggest that each assessment may be measuring a different physical quality. These results provide sport science practitioners with additional methods to assess RPA and provide useful information on the reliability and validity of these outcome measures. Additional research needs to be performed to examine the reliability and validity of the novel RPA assessments in other athletic populations and to determine the sensitivity of these measurements to training and injury.<\/jats:p>\n            <\/jats:sec>","DOI":"10.7717\/peerj.15553","type":"journal-article","created":{"date-parts":[[2023,6,20]],"date-time":"2023-06-20T07:53:02Z","timestamp":1687247582000},"page":"e15553","source":"Crossref","is-referenced-by-count":5,"title":["The reliability and validity of repeat power ability assessments and measurement indices in loaded vertical jumps"],"prefix":"10.7717","volume":"11","author":[{"given":"Alex O.","family":"Natera","sequence":"first","affiliation":[{"name":"Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia"},{"name":"Sport Science, New South Wales Institute of Sport, Sydney, New South Wales, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dale W.","family":"Chapman","sequence":"additional","affiliation":[{"name":"Curtin School of Allied Health, Curtin University, Perth, Western Australia, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neil D.","family":"Chapman","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Justin W.L.","family":"Keogh","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia"},{"name":"Sports Performance Research Centre New Zealand, Auckland University of Technology, Auckland,  New Zealand"},{"name":"Cluster for Health Improvement, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Sunshine Coast, Queensland, Australia"},{"name":"Kasturba Medical College, Manipal Academy of Higher Education, Manipal, Karnataka, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"4443","published-online":{"date-parts":[[2023,6,20]]},"reference":[{"issue":"1","key":"10.7717\/peerj.15553\/ref-1","doi-asserted-by":"publisher","first-page":"33","DOI":"10.1519\/14783.1","article-title":"Reliability assessment of ballistic jump squats and bench throws","volume":"19","author":"Alemany","year":"2005","journal-title":"The Journal of Strength and Conditioning Research"},{"issue":"2","key":"10.7717\/peerj.15553\/ref-2","first-page":"8","article-title":"The effects of combined weight and pneumatic training to enhance power endurance in tennis players","volume":"18","author":"Apanukul","year":"2015","journal-title":"Journal of Exercise Physiology"},{"issue":"7","key":"10.7717\/peerj.15553\/ref-3","doi-asserted-by":"publisher","first-page":"1898","DOI":"10.1519\/JSC.0b013e3181e83a5b","article-title":"Repeated high-intensity exercise in a professional rugby 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