medRxiv - Sports Medicine最新文献

{"title":"Fractal correlation properties of heart rate variability as a marker of exercise intensity during incremental and constant-speed treadmill running","authors":"Cody R van Rassel, Oluwatimilehin O Ajayi, Kate M Sales, Christian A Clermont, Markus Rummel, Martin J MacInnis","doi":"10.1101/2023.12.19.23300234","DOIUrl":"https://doi.org/10.1101/2023.12.19.23300234","url":null,"abstract":"The short–term scaling exponent of detrended fluctuation analysis (DFAα1) applied to interbeat intervals may provide a method to identify ventilatory thresholds and indicate systemic perturbation during prolonged exercise. The purposes of this study were to i) confirm whether DFAα1 values of 0.75 and 0.5 coincide with the gas exchange threshold (GET) and respiratory compensation point (RCP), ii) quantify DFAα1 during constant-speed running near the maximal lactate steady state (MLSS), and iii) assess the repeatability of DFAα1 between MLSS trials. Seventeen runners performed an incremental running test, and eleven and ten runners also performed constant–speed running 5% below, at, and 5% above the MLSS, and a repeat trial at MLSS, respectively. GET (bias [LOA]: –3.6 [–9.1 to 1.9] mL/kg/min) and RCP (–3.5 [–14.1 to 7.2] mL/kg/min) were overestimated using DFAα1. DFAα1 responses during 30-min running trials near MLSS were variable (i.e., 0.27 to 1.24), and affected by intensity (p=0.019) and duration (p=0.001). No difference in DFAα1 was detected between MLSS trials (p=0.926). These results question whether DFAα1 values can accurately delineate exercise thresholds, but the dependency of DFAα1 on intensity and duration support its potential use to quantify systemic perturbations imposed by continuous exercise.","PeriodicalId":501122,"journal":{"name":"medRxiv - Sports Medicine","volume":"486 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138823598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 6-week randomized-controlled field study: Effect of isokinetic eccentric resistance training on strength, flexibility and muscle structure for the shoulder external rotator in male junior handball players","authors":"Sebastian Vetter, Maren Witt, Pierre Hepp, Axel Schleichardt, Stefan Schleifenbaum, Christian Roth, Timm Denecke, Jeanette Henkelmann, Hans-Peter Koehler","doi":"10.1101/2023.12.06.23299595","DOIUrl":"https://doi.org/10.1101/2023.12.06.23299595","url":null,"abstract":"Background: Team handball involves a tremendous amount of shoulder motion with high forces during repeated extended external range of motion. Shoulder complaints are a common problem in youth handball players. While eccentric training for the lower extremity shows preventive effects by improving strength, range of motion and fascicle length, there is a research gap for the shoulder joint and for advanced tissue characterization using diffusion tensor imaging. Objectives: To investigate the effects of six-week eccentric isokinetic resistance training on the strength, flexibility, and fiber architecture characteristics of the external rotators compared to an active control group in junior handball players.\u0000Methods: 15 subjects were randomly assigned to the eccentric training group and 14 subjects to the active control group (conventional training). Primary outcome measures were eccentric and concentric isokinetic strength of the external rotators, range of motion, and muscle fascicle length and fascicle volume.\u0000Results: The intervention group, showed significant changes in eccentric strength (+15 %). The supraspinatus and infraspinatus muscles showed significant increases in fascicle length (+13 % and +8 %), and in fractional anisotropy (+9 % and 6 %), which were significantly different from the control group. Conclusions: Eccentric isokinetic training has a significant effect on the function and macroscopic structure of the shoulder external rotators in male junior handball players. While strength parameters and muscle structure improved, range of motion did not change. Future research is needed for more convenient field exercises in this context.","PeriodicalId":501122,"journal":{"name":"medRxiv - Sports Medicine","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138560063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of menstrual cycle and oral contraceptive phases on bone (re)modelling markers in response to intervallic running","authors":"Isabel Guisado-Cuadrado, Nuria Romero-Parra, Kirsty J. Elliott-Sale, Craig Sale, Ángel E. Díaz, Ana B. Peinado","doi":"10.1101/2023.11.29.23299199","DOIUrl":"https://doi.org/10.1101/2023.11.29.23299199","url":null,"abstract":"<strong>Objectives</strong> To examine procollagen type I N-propeptide (P1NP) and carboxy-terminal cross-linking telopeptide of type I collagen (β-CTX-1) concentrations across different phases of the menstrual (MC) and oral contraceptive (OC) cycles and in response to running.","PeriodicalId":501122,"journal":{"name":"medRxiv - Sports Medicine","volume":"28 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138511582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A within-person randomised trial to investigate the effects of a rigid cervical collar on three-dimensional angular movement and angular acceleration during emergency spinal immobilisation and extrication procedures in elite football (soccer) players: The RESTRICT study","authors":"Michael J Callaghan, Tom Hughes, John Davin, Russell Hayes, Neil Hough, Dan Torpey, David Perry, Sam Dawson, Eoghan Murray, Matthew Lancett, Anmin Liu, Richard K Jones","doi":"10.1101/2023.11.22.23298822","DOIUrl":"https://doi.org/10.1101/2023.11.22.23298822","url":null,"abstract":"<strong>Objective</strong> To determine the effects of rigid collars on cervical movement and acceleration during triple spinal immobilisation and extrication.","PeriodicalId":501122,"journal":{"name":"medRxiv - Sports Medicine","volume":"28 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138511581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Position: a study protocol for the prevention of fall injuries in French Special Forces selection courses using a body-centered intervention","authors":"Loucas Obligi, Matthieu Bertrand, Mathieu Boivent, Simon-Pierre Corcostegui, Pierre-Emmanuel Coz, Clement Derkenne, Vincent Des Robert, Victor Hurpin, Jauffrey Hus, Benoit L Hermitte, Laurent Lely, Edouard Patey, Emeric Romary, Luc Saint-Jean, Alexandre Trente, Marine Turpin, Nicolas Vertu, Charles Verdonk, Anais M Duffaud","doi":"10.1101/2023.07.13.23292623","DOIUrl":"https://doi.org/10.1101/2023.07.13.23292623","url":null,"abstract":"Introduction - The Military Physical and Sports Training program was developed by the French Army in order to train, optimize, and maintain individual readiness. Although the health benefits of sport practice do not need to be demonstrated, such activities can cause acute musculoskeletal injuries that need to be addressed. The prevalence of lower limb injury is rather high in the French military population and, in particular, ranges from 15 to 45% during Special Forces selection courses. Thus, this project aims to investigate the efficiency of a body-centered program designed to enhance body awareness. The program seeks to train the mind to actively pay attention to body information, while the latter is viewed as a protective factor against fall injuries. We assume: (i) that postural control can be improved by enhancing the level of body awareness; and (ii) that greater postural awareness could be beneficial in reducing the risk of fall injuries. The body-centered prevention program is based on the Optimization of the Resources of the Armed Forces (ORAF) intervention, which focuses on mental preparation and recovery, and has been deployed in the French Army for many years.\u0000Method and analyses - The study focuses on five French Special Forces selection courses (400 soldiers/ participants). It is divided into two stages (year 1, year 2). The first year is dedicated to data collection from the control group (200 participants), while in the second year the ORAF intervention will be deployed. The main objective is to evaluate the effectiveness of the ORAF intervention in reducing the rate of fall injuries during military selection, based on a multidisciplinary method that captures demographic, biological, biometric, clinical, and para-clinical measures. Registration number: IDRCB number 2021-A02108-33, Clinical Trial: NCT 05451394","PeriodicalId":501122,"journal":{"name":"medRxiv - Sports Medicine","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138511580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}