Pub Date : 2019-10-20DOI: 10.1080/17461391.2019.1675768
D. Teixeira, L. Pelletier, D. Monteiro, F. Rodrigues, J. Moutão, D. Marinho, L. Cid
Abstract Objective: The main objective of the present study was to examine the associations between coach-created task-involving climate and athletes’ intentions to continue practicing sport, through a serial mediation analysis that included basic psychological needs satisfaction (BPN), self-determined motivation (SDM) and enjoyment. Methods: Seven-hundred and ninety-nine elite swimmers (450 males, 349 females; aged 12–22 years, M = 16.65, SD = 2.83) participated in the present study. Groups were created according to age, years of experience, and gender. Results: Serial mediation analysis provided support for the proposed model where BPN's and enjoyment represent the most important mediators between task-involving climate and athletes’ intentions to continue sport practice. Conclusion: Enjoyment stands out as the most relevant predictor of intention to persist and as a significant mediator in the relation between task-involvement climate, BPN, SDM, and long-term sports practice. The task-involving climate created by coaches appears to set in motion a sequence where the satisfaction of basic needs and SDM lead to more enjoyment and increased persistence among young athletes.
{"title":"Motivational patterns in persistent swimmers: A serial mediation analysis","authors":"D. Teixeira, L. Pelletier, D. Monteiro, F. Rodrigues, J. Moutão, D. Marinho, L. Cid","doi":"10.1080/17461391.2019.1675768","DOIUrl":"https://doi.org/10.1080/17461391.2019.1675768","url":null,"abstract":"Abstract Objective: The main objective of the present study was to examine the associations between coach-created task-involving climate and athletes’ intentions to continue practicing sport, through a serial mediation analysis that included basic psychological needs satisfaction (BPN), self-determined motivation (SDM) and enjoyment. Methods: Seven-hundred and ninety-nine elite swimmers (450 males, 349 females; aged 12–22 years, M = 16.65, SD = 2.83) participated in the present study. Groups were created according to age, years of experience, and gender. Results: Serial mediation analysis provided support for the proposed model where BPN's and enjoyment represent the most important mediators between task-involving climate and athletes’ intentions to continue sport practice. Conclusion: Enjoyment stands out as the most relevant predictor of intention to persist and as a significant mediator in the relation between task-involvement climate, BPN, SDM, and long-term sports practice. The task-involving climate created by coaches appears to set in motion a sequence where the satisfaction of basic needs and SDM lead to more enjoyment and increased persistence among young athletes.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"39 8 1","pages":"660 - 669"},"PeriodicalIF":3.2,"publicationDate":"2019-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76513834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-17DOI: 10.1080/17461391.2019.1675767
C. Nicks, E. H. Martin
Abstract Research suggests that caffeine can enhance measures of muscular strength in the upper and lower extremities, although the literature is somewhat equivocal. Little is known on whether or not caffeine will improve maximal inspiratory pressure (MIP), a surrogate measure of inspiratory muscle strength. The purpose of the study was to determine the effects of a moderate dose of caffeine on inspiratory muscle function. Fifteen (8 male, 7 female) healthy adults (mean ± SD: age = 24.3 ± 6.4 years; height = 1.75 ± 0.11 m; body mass = 78.8 ± 16.5 kg) volunteered to participate in the study which used a double-blind, placebo-controlled, cross-over design. During the initial visit, baseline data was collected and participants were familiarized with inspiratory muscle measurements. For the second and third visits, participants ingested either a 5 mg kg−1 dose of caffeine (CAF) or placebo capsule (PL). After one hour, they completed at least 12 maximal inspiratory manoeuvres with 1 min rest between each attempt. MIP, maximal inspiratory peak pressure (PP), and maximal rate of pressure development (MRPD) were recorded. The CAF trial resulted in significantly higher MIP (154.7 ± 35.8 vs. 146.6 ± 37.6 cmH2O; p = 0.02) and PP (165.8 ± 36.8 vs. 158.3 cmH2O; p = 0.01) compared to the PL condition. No significant difference was observed in MRPD (p = 0.18). MIP and PP improved after ingestion of caffeine compared to the placebo condition. The findings from the study further establish caffeine’s potential ergogenic benefit on measures of muscular strength.
{"title":"Effects of caffeine on inspiratory muscle function","authors":"C. Nicks, E. H. Martin","doi":"10.1080/17461391.2019.1675767","DOIUrl":"https://doi.org/10.1080/17461391.2019.1675767","url":null,"abstract":"Abstract Research suggests that caffeine can enhance measures of muscular strength in the upper and lower extremities, although the literature is somewhat equivocal. Little is known on whether or not caffeine will improve maximal inspiratory pressure (MIP), a surrogate measure of inspiratory muscle strength. The purpose of the study was to determine the effects of a moderate dose of caffeine on inspiratory muscle function. Fifteen (8 male, 7 female) healthy adults (mean ± SD: age = 24.3 ± 6.4 years; height = 1.75 ± 0.11 m; body mass = 78.8 ± 16.5 kg) volunteered to participate in the study which used a double-blind, placebo-controlled, cross-over design. During the initial visit, baseline data was collected and participants were familiarized with inspiratory muscle measurements. For the second and third visits, participants ingested either a 5 mg kg−1 dose of caffeine (CAF) or placebo capsule (PL). After one hour, they completed at least 12 maximal inspiratory manoeuvres with 1 min rest between each attempt. MIP, maximal inspiratory peak pressure (PP), and maximal rate of pressure development (MRPD) were recorded. The CAF trial resulted in significantly higher MIP (154.7 ± 35.8 vs. 146.6 ± 37.6 cmH2O; p = 0.02) and PP (165.8 ± 36.8 vs. 158.3 cmH2O; p = 0.01) compared to the PL condition. No significant difference was observed in MRPD (p = 0.18). MIP and PP improved after ingestion of caffeine compared to the placebo condition. The findings from the study further establish caffeine’s potential ergogenic benefit on measures of muscular strength.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"170 1","pages":"813 - 818"},"PeriodicalIF":3.2,"publicationDate":"2019-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74881315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-10DOI: 10.1080/17461391.2019.1672793
G. Metsios, M. Wyon, K. Patel, Nick Allen, Y. Koutedakis
Abstract Using electrocardiography and echocardiography, we screened elite men and women ballet dancers for abnormal cardiovascular conditions using an observation design with blinded clinical analysis of cardiac function tests. Fifty-eight (females n = 33) elite professional ballet dancers (age: 26.0 ± 5.7 years, body mass index: 19.9 ± 2.2 kg/m2) with no past or present history of cardiovascular disease volunteered. Participants were assessed via a 12-lead electrocardiography and two-dimensional echocardiography for cardiac function. Electrocardiography revealed that 83% of the dancers demonstrated normal axis, while 31% had incomplete right bundle branch block and 17% had sinus bradycardia; none showed any abnormal findings. Findings from the echocardiography were also normal for all participants and comparable to their counterparts in other sports. Significant differences (p < 0.05) were detected in almost all studied echocardiographic parameters between males and females. In conclusion, heart function and structure seem to be normal in elite ballet dancers, placing them at low risk for sudden cardiac death and performance-related cardiovascular complications. Larger samples are required to confirm these findings.
{"title":"Dancers’ heart: Cardiac screening in elite dancers","authors":"G. Metsios, M. Wyon, K. Patel, Nick Allen, Y. Koutedakis","doi":"10.1080/17461391.2019.1672793","DOIUrl":"https://doi.org/10.1080/17461391.2019.1672793","url":null,"abstract":"Abstract Using electrocardiography and echocardiography, we screened elite men and women ballet dancers for abnormal cardiovascular conditions using an observation design with blinded clinical analysis of cardiac function tests. Fifty-eight (females n = 33) elite professional ballet dancers (age: 26.0 ± 5.7 years, body mass index: 19.9 ± 2.2 kg/m2) with no past or present history of cardiovascular disease volunteered. Participants were assessed via a 12-lead electrocardiography and two-dimensional echocardiography for cardiac function. Electrocardiography revealed that 83% of the dancers demonstrated normal axis, while 31% had incomplete right bundle branch block and 17% had sinus bradycardia; none showed any abnormal findings. Findings from the echocardiography were also normal for all participants and comparable to their counterparts in other sports. Significant differences (p < 0.05) were detected in almost all studied echocardiographic parameters between males and females. In conclusion, heart function and structure seem to be normal in elite ballet dancers, placing them at low risk for sudden cardiac death and performance-related cardiovascular complications. Larger samples are required to confirm these findings.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"48 1","pages":"920 - 925"},"PeriodicalIF":3.2,"publicationDate":"2019-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76359220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-10DOI: 10.1080/17461391.2019.1670867
G. Weir, H. Wyatt, R. van Emmerik, Matthieu Trudeau, Steffen Willwacher, G. Brüggemann, J. Hamill
ABSTRACT The purpose of this study was to investigate changes in coordination variability (CV) over the course of a prolonged treadmill run and the influence of stability and neutral footwear on CV. Fourteen male habitually rearfoot runners completed two 42 min prolonged running sessions while three-dimensional kinematics and kinetics were recorded. During the first 21 min, participants ran in a neutral shoe (baseline run), then changed into either another neutral shoe of the same construction but another colour or a stability shoe and ran a further 21 min (intervention run). A modified vector coding technique was used to compute thigh-leg, leg-rearfoot and rearfoot-forefoot segment CV. Following the baseline run, thigh flexion/extension-leg flexion/extension, rearfoot inversion/eversion-forefoot plantar flexion/dorsiflexion and rearfoot inversion/eversion-forefoot adduction/abduction CV increased (p < .05). During the intervention run, CV was higher in the neutral shoe compared with the stability shoe for thigh flexion/extension-leg flexion/extension and leg flexion/extension-rearfoot inversion/eversion couplings (p < .05). Lower extremity CV increased or was maintained during a prolonged treadmill run in healthy male rearfoot runners, likely to distribute stresses among the tissues as muscles begin to fatigue. CV increased to a greater extent in neutral compared with stability footwear which may be a result of: (1) the stability shoe acting as a perturbation to the runner and their response is to regulate CV, or; (2) stability footwear provides greater support and consequently, runners do not need to explore additional degrees of freedom to reduce stresses applied to the tissues throughout a prolonged run.
{"title":"Influence of neutral and stability athletic footwear on lower extremity coordination variability during a prolonged treadmill run in male rearfoot runners","authors":"G. Weir, H. Wyatt, R. van Emmerik, Matthieu Trudeau, Steffen Willwacher, G. Brüggemann, J. Hamill","doi":"10.1080/17461391.2019.1670867","DOIUrl":"https://doi.org/10.1080/17461391.2019.1670867","url":null,"abstract":"ABSTRACT The purpose of this study was to investigate changes in coordination variability (CV) over the course of a prolonged treadmill run and the influence of stability and neutral footwear on CV. Fourteen male habitually rearfoot runners completed two 42 min prolonged running sessions while three-dimensional kinematics and kinetics were recorded. During the first 21 min, participants ran in a neutral shoe (baseline run), then changed into either another neutral shoe of the same construction but another colour or a stability shoe and ran a further 21 min (intervention run). A modified vector coding technique was used to compute thigh-leg, leg-rearfoot and rearfoot-forefoot segment CV. Following the baseline run, thigh flexion/extension-leg flexion/extension, rearfoot inversion/eversion-forefoot plantar flexion/dorsiflexion and rearfoot inversion/eversion-forefoot adduction/abduction CV increased (p < .05). During the intervention run, CV was higher in the neutral shoe compared with the stability shoe for thigh flexion/extension-leg flexion/extension and leg flexion/extension-rearfoot inversion/eversion couplings (p < .05). Lower extremity CV increased or was maintained during a prolonged treadmill run in healthy male rearfoot runners, likely to distribute stresses among the tissues as muscles begin to fatigue. CV increased to a greater extent in neutral compared with stability footwear which may be a result of: (1) the stability shoe acting as a perturbation to the runner and their response is to regulate CV, or; (2) stability footwear provides greater support and consequently, runners do not need to explore additional degrees of freedom to reduce stresses applied to the tissues throughout a prolonged run.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"163 1","pages":"776 - 782"},"PeriodicalIF":3.2,"publicationDate":"2019-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80285717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-10-06DOI: 10.1080/17461391.2019.1669716
Laurent Chapelle, Bruno Tassignon, Nikki Rommers, Nikki Rommers, Nikki Rommers, Evelien Mertens, Evelien Mertens, P. Mullie, P. Clarys
ABSTRACT Pre-exercise hypohydration can impair soccer performance and has been extensively studied in different soccer populations. Therefore, the aim of this systematic review was to report hypohydration prevalence, measured by blood or urine samples, in different soccer populations based on sex (males and females), performance level (professional and recreational players) and context (training sessions and games). The Pubmed, Web of Science and SPORTDiscus databases were systematically searched until November 2018. Data were pooled to compare hypohydration prevalence between the different subgroups. Following the systematic search selection process, 24 studies were included. The results indicated that overall pre-exercise hypohydration prevalence was 63.3%, 37.4% and 58.8% for urine specific gravity (USG), urine osmolality (U Osm) and urine colour, respectively. Furthermore, no study implemented blood samples to examine hypohydration prevalence in soccer players. The subgroup analyses using USG data indicated that pre-exercise hypohydration prevalence was significantly higher amongst males (66.0%; p = 0.001), professional soccer players (66.2%; p = 0.020) and before a training session (79.6%; p < 0.001). Pre-exercise hypohydration prevalence was 46.8% among female soccer players, 55.6% in recreational soccer players and 41,3% before a game. The subgroup analyses using U Osm data indicated that hypohydration prevalence was significantly higher before a training session (52.6%; p = 0.023). Based on these results, it can be concluded that hypohydration prevalence in soccer players is of major concern. Future research should explore how pre-exercise hydration status can be improved in a sustainable way.
{"title":"Pre-exercise hypohydration prevalence in soccer players: A quantitative systematic review.","authors":"Laurent Chapelle, Bruno Tassignon, Nikki Rommers, Nikki Rommers, Nikki Rommers, Evelien Mertens, Evelien Mertens, P. Mullie, P. Clarys","doi":"10.1080/17461391.2019.1669716","DOIUrl":"https://doi.org/10.1080/17461391.2019.1669716","url":null,"abstract":"ABSTRACT Pre-exercise hypohydration can impair soccer performance and has been extensively studied in different soccer populations. Therefore, the aim of this systematic review was to report hypohydration prevalence, measured by blood or urine samples, in different soccer populations based on sex (males and females), performance level (professional and recreational players) and context (training sessions and games). The Pubmed, Web of Science and SPORTDiscus databases were systematically searched until November 2018. Data were pooled to compare hypohydration prevalence between the different subgroups. Following the systematic search selection process, 24 studies were included. The results indicated that overall pre-exercise hypohydration prevalence was 63.3%, 37.4% and 58.8% for urine specific gravity (USG), urine osmolality (U Osm) and urine colour, respectively. Furthermore, no study implemented blood samples to examine hypohydration prevalence in soccer players. The subgroup analyses using USG data indicated that pre-exercise hypohydration prevalence was significantly higher amongst males (66.0%; p = 0.001), professional soccer players (66.2%; p = 0.020) and before a training session (79.6%; p < 0.001). Pre-exercise hypohydration prevalence was 46.8% among female soccer players, 55.6% in recreational soccer players and 41,3% before a game. The subgroup analyses using U Osm data indicated that hypohydration prevalence was significantly higher before a training session (52.6%; p = 0.023). Based on these results, it can be concluded that hypohydration prevalence in soccer players is of major concern. Future research should explore how pre-exercise hydration status can be improved in a sustainable way.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"13 1","pages":"744 - 755"},"PeriodicalIF":3.2,"publicationDate":"2019-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83817630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-30DOI: 10.1080/17461391.2019.1669717
Antoine Raberin, Henri Meric, P. Mucci, J. Ayerbe, F. Durand
Abstract The objective of the present study was to evaluate the influence of exercise-induced hypoxemia (EIH) on muscle and cerebral oxygenation responses during maximal exercise in normoxia and in acute moderate hypoxia (fraction of inspired oxygen: 15.3%, 2400 m). EIH was defined as a drop in hemoglobin saturation of at least 4% for at least three consecutive minutes during maximal exercise at sea level. Twenty-five athletes performed incremental treadmill tests to assess maximal oxygen consumption (VO2max) in normoxia and in hypoxia. Oxygenation of the vastus lateralis muscle and the left prefrontal cortex of the brain was monitored using near-infrared spectroscopy. During the normoxic test, 15 athletes exhibited EIH; they displayed a larger change in muscle levels of oxyhemoglobin (ΔO2Hb) (p = 0.04) and a greater change in cerebral levels of deoxyhemoglobin (ΔHHb) (p = 0.02) than athletes without EIH (NEIH group). During the hypoxic test, muscle ΔO2Hb was lower in the EIH group than in the NEIH group (p = 0.03). At VO2max, hypoxia was associated with a smaller cerebral ΔO2Hb in both groups, and a greater cerebral ΔHHb compared to normoxia in the NEIH group only (p = 0.02). No intergroup differences in changes in muscle oxygenation were observed. The severity of O2 arterial desaturation was negatively correlated with changes in total muscle hemoglobin in normoxia (r = −0.48, p = 0.01), and positively correlated with the cerebral ΔHHb in normoxia (r = 0.45, p = 0.02). The occurrence of EIH at sea level was associated with specific muscle and cerebral oxygenation responses to exercise under both normoxia and moderate hypoxia.
{"title":"Muscle and cerebral oxygenation during exercise in athletes with exercise-induced hypoxemia: A comparison between sea level and acute moderate hypoxia","authors":"Antoine Raberin, Henri Meric, P. Mucci, J. Ayerbe, F. Durand","doi":"10.1080/17461391.2019.1669717","DOIUrl":"https://doi.org/10.1080/17461391.2019.1669717","url":null,"abstract":"Abstract The objective of the present study was to evaluate the influence of exercise-induced hypoxemia (EIH) on muscle and cerebral oxygenation responses during maximal exercise in normoxia and in acute moderate hypoxia (fraction of inspired oxygen: 15.3%, 2400 m). EIH was defined as a drop in hemoglobin saturation of at least 4% for at least three consecutive minutes during maximal exercise at sea level. Twenty-five athletes performed incremental treadmill tests to assess maximal oxygen consumption (VO2max) in normoxia and in hypoxia. Oxygenation of the vastus lateralis muscle and the left prefrontal cortex of the brain was monitored using near-infrared spectroscopy. During the normoxic test, 15 athletes exhibited EIH; they displayed a larger change in muscle levels of oxyhemoglobin (ΔO2Hb) (p = 0.04) and a greater change in cerebral levels of deoxyhemoglobin (ΔHHb) (p = 0.02) than athletes without EIH (NEIH group). During the hypoxic test, muscle ΔO2Hb was lower in the EIH group than in the NEIH group (p = 0.03). At VO2max, hypoxia was associated with a smaller cerebral ΔO2Hb in both groups, and a greater cerebral ΔHHb compared to normoxia in the NEIH group only (p = 0.02). No intergroup differences in changes in muscle oxygenation were observed. The severity of O2 arterial desaturation was negatively correlated with changes in total muscle hemoglobin in normoxia (r = −0.48, p = 0.01), and positively correlated with the cerebral ΔHHb in normoxia (r = 0.45, p = 0.02). The occurrence of EIH at sea level was associated with specific muscle and cerebral oxygenation responses to exercise under both normoxia and moderate hypoxia.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"8 1","pages":"803 - 812"},"PeriodicalIF":3.2,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79988998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-29DOI: 10.1080/17461391.2019.1669715
C. Lazzari, F. Diefenthaeler, J. L. B. Marques
Abstract Cycling ergometer protocols are commonly integrated with a virtual reality environment (VRE), especially because of its static position that also allows multiple exercise experiments. Concerning VRE scenarios, visually delayed situations like the ones produced at excessive low update rates can also affect the sense of presence and physiological responses. However, the main interface between the subject and a cycling VRE is the power applied over the crank, and there are only a few experiments to evaluate the effect of delayed situations on this particular interface. Thus, this work aims to investigate the effects of the power update rate (PUR) over the subject`s performance on an avatar-based simulator during a drafting task. A custom cycling VRE was built, and 21 male recreational cyclists (175.9 ± 7.5 cm; 76.5 ± 13.9 kg) were tested at six different PUR levels from 100 to 3000 ms. As a result, PUR affects performance scores (virtual distance, efficiency, and heart rate, p < 0.01) at the given VRE conditions. The case-by-case analysis of the groups reveals that higher update rates always lead to a statistical equivalent or superior performance. Nevertheless, no parameter shows any group difference between 500 ms and lower PUR. These results suggest that virtual cycling protocols should consider PUR and other delay-related mechanisms as possible intervening factors over physiological responses and performance scores.
{"title":"Virtual cycling effort is dependent on power update rate","authors":"C. Lazzari, F. Diefenthaeler, J. L. B. Marques","doi":"10.1080/17461391.2019.1669715","DOIUrl":"https://doi.org/10.1080/17461391.2019.1669715","url":null,"abstract":"Abstract Cycling ergometer protocols are commonly integrated with a virtual reality environment (VRE), especially because of its static position that also allows multiple exercise experiments. Concerning VRE scenarios, visually delayed situations like the ones produced at excessive low update rates can also affect the sense of presence and physiological responses. However, the main interface between the subject and a cycling VRE is the power applied over the crank, and there are only a few experiments to evaluate the effect of delayed situations on this particular interface. Thus, this work aims to investigate the effects of the power update rate (PUR) over the subject`s performance on an avatar-based simulator during a drafting task. A custom cycling VRE was built, and 21 male recreational cyclists (175.9 ± 7.5 cm; 76.5 ± 13.9 kg) were tested at six different PUR levels from 100 to 3000 ms. As a result, PUR affects performance scores (virtual distance, efficiency, and heart rate, p < 0.01) at the given VRE conditions. The case-by-case analysis of the groups reveals that higher update rates always lead to a statistical equivalent or superior performance. Nevertheless, no parameter shows any group difference between 500 ms and lower PUR. These results suggest that virtual cycling protocols should consider PUR and other delay-related mechanisms as possible intervening factors over physiological responses and performance scores.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"32 1","pages":"831 - 838"},"PeriodicalIF":3.2,"publicationDate":"2019-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78390076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-26DOI: 10.1080/17461391.2019.1668063
Sergi Nuell, V. Illera-Domínguez, G. Carmona, X. Alomar, J. Padullés, M. Lloret, J. Cadefau
Abstract This study aimed to analyse changes in sprint performance, muscle volumes (MVs) and sprint mechanical parameters (SMPs) in national-level sprinters performing a 5-month indoor sprint-based training macrocycle (SBTM). Twelve well-trained sprinters were tested on three different occasions throughout the SBTM. Testing procedures included: sprint performance over 10m, 40m, 80m, 150m, and 300m; MRI of thighs, to compute MVs of quadriceps, hamstrings and adductors; and a 40m sprint using a radar gun to assess SMPs such as theoretical maximal horizontal force, theoretical maximal horizontal velocity (V0), maximal power and index of force application (DRF). Improvements in sprint performance of between 4% and 7% (ES = 0.46–1.11, P < 0.01) were accompanied by increments in: quadriceps of 6% (ES = 0.41, P < 0.01), hamstrings of 10% (ES = 0.62, P < 0.01), adductors of 12% (ES = 0.87, P < 0.01), V0 of 5% (ES = 0.40, P < 0.01) and DRF of 7% (ES = 0.91, P < 0.01). In conclusion, during the SBTM after the off-season, moderate hypertrophic changes occur in sprinters. Moreover, the greater increase in hamstrings and adductors, compared with quadriceps, might be related to the prominent role of these muscle groups in sprinting. Furthermore, the SBTM was likely effective at developing sprint performance in sprinters, thereby endorsing the idea that sprint-specific training is crucial for highly trained individuals. Finally, our results support the notion that V0 or the “velocity-oriented” force–velocity profile is determinant of performance in sprinters.
摘要:本研究旨在分析国家级短跑运动员进行为期5个月的室内大循环训练(SBTM)后短跑成绩、肌肉体积(MVs)和短跑力学参数(SMPs)的变化。12名训练有素的短跑运动员在整个SBTM的三个不同场合接受了测试。测试程序包括:10米、40米、80米、150米、300米短跑成绩;大腿MRI，计算股四头肌、腘绳肌和内收肌的mv;和40米短跑用雷达枪评估smp，如理论最大水平力，理论最大水平速度(V0)，最大功率和力施加指数(DRF)。短跑成绩提高4% ~ 7% (ES = 0.46 ~ 1.11, P < 0.01)，同时股四头肌增加6% (ES = 0.41, P < 0.01)，腘绳肌增加10% (ES = 0.62, P < 0.01)，内收肌增加12% (ES = 0.87, P < 0.01)， V0增加5% (ES = 0.40, P < 0.01)， DRF增加7% (ES = 0.91, P < 0.01)。总之，在淡季后的SBTM期间，短跑运动员会发生中度肥厚变化。此外，与四头肌相比，腘绳肌和内收肌的增加更大，可能与这些肌肉群在短跑中的突出作用有关。此外，SBTM可能有效地培养短跑运动员的短跑成绩，从而支持短跑专项训练对训练有素的个人至关重要的观点。最后，我们的研究结果支持这样的观点，即V0或“速度导向”力-速度分布是短跑运动员成绩的决定因素。
{"title":"Hypertrophic muscle changes and sprint performance enhancement during a sprint-based training macrocycle in national-level sprinters","authors":"Sergi Nuell, V. Illera-Domínguez, G. Carmona, X. Alomar, J. Padullés, M. Lloret, J. Cadefau","doi":"10.1080/17461391.2019.1668063","DOIUrl":"https://doi.org/10.1080/17461391.2019.1668063","url":null,"abstract":"Abstract\u0000 This study aimed to analyse changes in sprint performance, muscle volumes (MVs) and sprint mechanical parameters (SMPs) in national-level sprinters performing a 5-month indoor sprint-based training macrocycle (SBTM). Twelve well-trained sprinters were tested on three different occasions throughout the SBTM. Testing procedures included: sprint performance over 10m, 40m, 80m, 150m, and 300m; MRI of thighs, to compute MVs of quadriceps, hamstrings and adductors; and a 40m sprint using a radar gun to assess SMPs such as theoretical maximal horizontal force, theoretical maximal horizontal velocity (V0), maximal power and index of force application (DRF). Improvements in sprint performance of between 4% and 7% (ES = 0.46–1.11, P < 0.01) were accompanied by increments in: quadriceps of 6% (ES = 0.41, P < 0.01), hamstrings of 10% (ES = 0.62, P < 0.01), adductors of 12% (ES = 0.87, P < 0.01), V0 of 5% (ES = 0.40, P < 0.01) and DRF of 7% (ES = 0.91, P < 0.01). In conclusion, during the SBTM after the off-season, moderate hypertrophic changes occur in sprinters. Moreover, the greater increase in hamstrings and adductors, compared with quadriceps, might be related to the prominent role of these muscle groups in sprinting. Furthermore, the SBTM was likely effective at developing sprint performance in sprinters, thereby endorsing the idea that sprint-specific training is crucial for highly trained individuals. Finally, our results support the notion that V0 or the “velocity-oriented” force–velocity profile is determinant of performance in sprinters.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"46 1","pages":"793 - 802"},"PeriodicalIF":3.2,"publicationDate":"2019-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73080244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-26DOI: 10.1080/17461391.2019.1668481
A. Silva, Catarina L. Nunes, C. Matias, P. Rocha, C. Minderico, S. Heymsfield, H. Lukaski, L. Sardinha
Abstract Bioelectrical impedance (BI) has been widely used but clarification about the behaviour of raw BI measurements under specific athletic conditions is required. Thus, we determined the usefulness of raw BI measures in tracking body fluids changes during the preparation period prior to competition in elite Judo athletes. At baseline (weight stability), 27 male athletes were evaluated (23.2 ± 2.8y) and again 1–3 days before competition (∼1–2 months apart). Athletes were free to gain/lost weight based upon specific competition needs. Using dilution techniques (deuterium and bromide), total-body water (TBW) and extracellular water were estimated, and intracellular water calculated as TBW minus extracellular water. Body fluid distribution was determined as Extra-to-/Intracellular water (E/I). Fat and fat-free mass (FFM) was assessed by dual-energy x-ray absorptiometry. Resistance, reactance, and phase angle (PhA) were obtained from bioelectrical impedance spectroscopy (50-kHz frequency). No differences in raw BI measures were observed between athletes that lost (N = 17) or gain weight (N = 10), except for fat, FFM, extracellular water, and EI (p < 0.05). After adjusting for FFM and height, resistance explained TBW (β = −0.047, p = 0.002) and extracelular water (β = −0.025, p = 0.001). Reactance explained ECW (β = −0.098, p = 0.004) and EI (β = −0.004, p = 0.006), while PhA predicted TBW (β = 1.609, p = 0.047), ICW (β = 1.899, p = 0.001) and EI (β = −0.056, p = 0.001). Regardless of body composition changes, athletes who increase reactance and resistance reduced extracellular water and body fluids while those who raised PhA increased intracellular water. Judo athletes who reduced weight, decreased FFM but cellular health was not compromised, as PhA remained stable and, consequently, cell hydration.
{"title":"Usefulness of raw bioelectrical impedance parameters in tracking fluid shifts in judo athletes","authors":"A. Silva, Catarina L. Nunes, C. Matias, P. Rocha, C. Minderico, S. Heymsfield, H. Lukaski, L. Sardinha","doi":"10.1080/17461391.2019.1668481","DOIUrl":"https://doi.org/10.1080/17461391.2019.1668481","url":null,"abstract":"Abstract Bioelectrical impedance (BI) has been widely used but clarification about the behaviour of raw BI measurements under specific athletic conditions is required. Thus, we determined the usefulness of raw BI measures in tracking body fluids changes during the preparation period prior to competition in elite Judo athletes. At baseline (weight stability), 27 male athletes were evaluated (23.2 ± 2.8y) and again 1–3 days before competition (∼1–2 months apart). Athletes were free to gain/lost weight based upon specific competition needs. Using dilution techniques (deuterium and bromide), total-body water (TBW) and extracellular water were estimated, and intracellular water calculated as TBW minus extracellular water. Body fluid distribution was determined as Extra-to-/Intracellular water (E/I). Fat and fat-free mass (FFM) was assessed by dual-energy x-ray absorptiometry. Resistance, reactance, and phase angle (PhA) were obtained from bioelectrical impedance spectroscopy (50-kHz frequency). No differences in raw BI measures were observed between athletes that lost (N = 17) or gain weight (N = 10), except for fat, FFM, extracellular water, and EI (p < 0.05). After adjusting for FFM and height, resistance explained TBW (β = −0.047, p = 0.002) and extracelular water (β = −0.025, p = 0.001). Reactance explained ECW (β = −0.098, p = 0.004) and EI (β = −0.004, p = 0.006), while PhA predicted TBW (β = 1.609, p = 0.047), ICW (β = 1.899, p = 0.001) and EI (β = −0.056, p = 0.001). Regardless of body composition changes, athletes who increase reactance and resistance reduced extracellular water and body fluids while those who raised PhA increased intracellular water. Judo athletes who reduced weight, decreased FFM but cellular health was not compromised, as PhA remained stable and, consequently, cell hydration.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"3 1","pages":"734 - 743"},"PeriodicalIF":3.2,"publicationDate":"2019-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87130934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-09-24DOI: 10.1080/17461391.2019.1664639
M. Baggaley, G. Vernillo, Aaron Martínez, N. Horvais, M. Giandolini, G. Millet, W. B. Edwards
Abstract We sought to examine the effect of step length manipulation on energy absorption and impact attenuation during graded running. Nineteen runners (10F, 9M) ran on an instrumented treadmill at three step lengths (preferred and ±10% preferred) at each of five grades (0°, ±5°, and ±10°) while 3D motion data were captured. Speed was held constant at 3.33 m/s and step length was manipulated by syncing cadence to a metronome. Manipulating step length altered energy absorption (p ≤ 0.002) and impact attenuation (p < 0.0001) across all grades. Energy absorption at the knee joint was most responsive to step length manipulations [Δ range (±10%SL-PrefSL) = 0.076–0.126 J/kg, p < 0.0001], followed by the ankle (Δ range = 0.026–0.100 J/kg, p = 0.001) and hip (Δ range = 0.008–0.018 J/kg, p < 0.006). Shortening step length reduced knee joint energy absorption at all grades with the smallest effect observed during uphill running (Δ ≥ −0.053 J/kg), while large reductions occurred during level (Δ = −0.096 J/kg) and downhill running (Δ ≥ −0.108 J/kg). Increasing step length resulted in greater knee joint energy absorption (p ≤ 0.037) across all grades of running. Impact attenuation was greatest at long step lengths (Δ = 2.708) and lowest at short step lengths (Δ = −2.061), compared to preferred. Overall, Step length influenced the energy absorption and impact attenuation characteristics of the lower extremity during level and graded running. Adopting a shorter step length may be a useful intervention to reduce knee joint loading, particularly during downhill or level running. Elongating step length placed a greater demand on the lower extremity joints, which may expedite the development of neuromuscular fatigue.
摘要:我们试图研究步长控制对分级跑步过程中能量吸收和冲击衰减的影响。19名跑步者(10F, 9M)在仪器化的跑步机上以3种步长(优选和±10%优选)在5个等级(0°，±5°和±10°)中的每一种上跑步，同时捕获3D运动数据。速度保持在3.33米/秒恒定，步长通过同步节奏来控制节拍器。控制步长改变了所有等级的能量吸收(p≤0.002)和冲击衰减(p < 0.0001)。膝关节的能量吸收对步长操作反应最灵敏[Δ范围(±10%SL-PrefSL) = 0.076-0.126 J/kg, p < 0.0001]，其次是踝关节(Δ范围= 0.026-0.100 J/kg, p = 0.001)和髋关节(Δ范围= 0.008-0.018 J/kg, p < 0.006)。缩短步长降低了所有级别的膝关节能量吸收，上坡跑(Δ≥−0.053 J/kg)效果最小，水平跑(Δ =−0.096 J/kg)和下坡跑(Δ≥−0.108 J/kg)效果最大。在所有级别的跑步中，增加步长导致更大的膝关节能量吸收(p≤0.037)。与优选相比，长步长时冲击衰减最大(Δ = 2.708)，短步长时最小(Δ =−2.061)。总的来说，步长影响了水平和分级跑步时下肢的能量吸收和冲击衰减特性。采用较短的步长可能是减少膝关节负荷的有效干预措施，特别是在下坡或水平跑步时。延长步长对下肢关节的要求更高，这可能加速神经肌肉疲劳的发展。
{"title":"Step length and grade effects on energy absorption and impact attenuation in running","authors":"M. Baggaley, G. Vernillo, Aaron Martínez, N. Horvais, M. Giandolini, G. Millet, W. B. Edwards","doi":"10.1080/17461391.2019.1664639","DOIUrl":"https://doi.org/10.1080/17461391.2019.1664639","url":null,"abstract":"Abstract\u0000 We sought to examine the effect of step length manipulation on energy absorption and impact attenuation during graded running. Nineteen runners (10F, 9M) ran on an instrumented treadmill at three step lengths (preferred and ±10% preferred) at each of five grades (0°, ±5°, and ±10°) while 3D motion data were captured. Speed was held constant at 3.33 m/s and step length was manipulated by syncing cadence to a metronome. Manipulating step length altered energy absorption (p ≤ 0.002) and impact attenuation (p < 0.0001) across all grades. Energy absorption at the knee joint was most responsive to step length manipulations [Δ range (±10%SL-PrefSL) = 0.076–0.126 J/kg, p < 0.0001], followed by the ankle (Δ range = 0.026–0.100 J/kg, p = 0.001) and hip (Δ range = 0.008–0.018 J/kg, p < 0.006). Shortening step length reduced knee joint energy absorption at all grades with the smallest effect observed during uphill running (Δ ≥ −0.053 J/kg), while large reductions occurred during level (Δ = −0.096 J/kg) and downhill running (Δ ≥ −0.108 J/kg). Increasing step length resulted in greater knee joint energy absorption (p ≤ 0.037) across all grades of running. Impact attenuation was greatest at long step lengths (Δ = 2.708) and lowest at short step lengths (Δ = −2.061), compared to preferred. Overall, Step length influenced the energy absorption and impact attenuation characteristics of the lower extremity during level and graded running. Adopting a shorter step length may be a useful intervention to reduce knee joint loading, particularly during downhill or level running. Elongating step length placed a greater demand on the lower extremity joints, which may expedite the development of neuromuscular fatigue.","PeriodicalId":12061,"journal":{"name":"European Journal of Sport Science","volume":"193 1","pages":"756 - 766"},"PeriodicalIF":3.2,"publicationDate":"2019-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79063622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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