Heart rhythm assessment in elite endurance athletes: A better method?

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The training and development of elite sprint performance: an integration of scientific and best practice literature

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Maximal aerobic power characteristics of male professional soccer players, 1989-2012

Purpose: The purpose of this investigation was to quantify maximal aerobic power (VO2max) in soccer as a function of performance level, position, age, and time of season. In addition, the authors examined the evolution Of VO2max among professional players over a 23-y period. Methods: 1545 male soccer players (22 +/- 4 y, 76 +/- 8 kg, 181 +/- 6 cm) were tested for VO2max at the Norwegian Olympic Training Center between 1989 and 2012. Results: No differences in VO2max were observed among national-team players, 1st- and 2nd-division players, and juniors. Midfielders had higher VO2max than defenders; forwards, and goalkeepers (P < .05). Players <18 y of age had similar to 3% higher VO2max than 23- to 26-y-old players (P = .016). The players had 1.6% and 2.1% lower VO2max during off-season than preseason (P = .046) and in season (P = .021), respectively. Relative to body mass, VO2max among the professional players in this study has not improved over time. Professional players tested during 2006-2012 actually had 3.2% lower VO2max than those tested from 2000 to 2006 (P = .001). Conclusions: This study provides effect-magnitude estimates for the influence of performance level, player position, age, and season time on VO2max in men's elite soccer. The findings from a robust data set indicate that VO2max values similar to 62-64 mL . kg(-1) . min(-1) fulfill the demands for aerobic capacity in men's professional soccer and that VO2max is not a clearly distinguishing variable separating players of different standards

Crossing the Golden Training Divide: The Science and Practice of Training World‑Class 800‑ and 1500‑m Runners

Despite an increasing amount of research devoted to middle-distance training (herein the 800 and 1500 m events), information regarding the training methodologies of world-class runners is limited. Therefore, the objective of this review was to integrate scientific and best practice literature and outline a novel framework for understanding the training and development of elite middle-distance performance. Herein, we describe how well-known training principles and fundamental training characteristics are applied by world-leading middle-distance coaches and athletes to meet the physiological and neuromuscular demands of 800 and 1500 m. Large diversities in physiological profiles and training emerge among middle-distance runners, justifying a categorization into types across a continuum (400–800 m types, 800 m specialists, 800–1500 m types, 1500 m specialists and 1500–5000 m types). Larger running volumes (120–170 vs. 50–120 km·week−1 during the preparation period) and higher aerobic/anaerobic training distribution (90/10 vs. 60/40% of the annual running sessions below vs. at or above anaerobic threshold) distinguish 1500- and 800-m runners. Lactate tolerance and lactate production training are regularly included interval sessions by middle-distance runners, particularly among 800-m athletes. In addition, 800-m runners perform more strength, power and plyometric training than 1500-m runners. Although the literature is biased towards men and “long-distance thinking,” this review provides a point of departure for scientists and practitioners to further explore and quantify the training and development of elite 800- and 1500-m running performance and serves as a position statement for outlining current state-of-the-art middle-distance training recommendations.publishedVersio

The relationship between physical activity and physical self-esteem in adolescents: The role of physical fitness indices

Publised version of an article from the journal: Pediatric Exercise Science. Also available from Human Kinetics: http://journals.humankinetics.com/pes-back-issues/pes-volume-25-issue-1-february/the-relationship-between-physical-activity-and-physical-self-esteem-in-adolescents-the-role-of-physical-fitness-indicesThe aim of this study was to investigate if physical fitness (strength/power, endurance, flexibility and coordination) mediates the cross-sectional relationship between physical activity and physical self-perception (athletic competence and physical appearance) in a sample of 15-year old adolescents. We wanted to investigate the relative strength of each indirect effect. The present data are taken from two waves of a larger data collection for the project "Youth in Balance", and was collected in the autumn of 2005 (N = 1207) and 2008 (N = 632). A total of 1839 students (889 girls and 950 boys) from 12 schools in Kristiansand took part. A bias-corrected bootstrapping technique was used to examine indirect effects. Results revealed that cardiovascular endurance, lower-body strength/power, and upper-body strength stood out as unique mediators in the relationship between physical activity and athletic competence in both genders. Furthermore, there was an indirect effect of physical activity on physical appearance through physical strength/power and flexibility in males. No indirect effects of physical activity on physical appearance through actual physical fitness indices were detected in females

Assessment of healthcare worker protocol deviations and self-contamination during personal protective equipment donning and doffing

OBJECTIVETo evaluate healthcare worker (HCW) risk of self-contamination when donning and doffing personal protective equipment (PPE) using fluorescence and MS2 bacteriophage.DESIGNProspective pilot study.SETTINGTertiary-care hospital.PARTICIPANTSA total of 36 HCWs were included in this study: 18 donned/doffed contact precaution (CP) PPE and 18 donned/doffed Ebola virus disease (EVD) PPE.INTERVENTIONSHCWs donned PPE according to standard protocols. Fluorescent liquid and MS2 bacteriophage were applied to HCWs. HCWs then doffed their PPE. After doffing, HCWs were scanned for fluorescence and swabbed for MS2. MS2 detection was performed using reverse transcriptase PCR. The donning and doffing processes were videotaped, and protocol deviations were recorded.RESULTSOverall, 27% of EVD PPE HCWs and 50% of CP PPE HCWs made ≥1 protocol deviation while donning, and 100% of EVD PPE HCWs and 67% of CP PPE HCWs made ≥1 protocol deviation while doffing (P=.02). The median number of doffing protocol deviations among EVD PPE HCWs was 4, versus 1 among CP PPE HCWs. Also, 15 EVD PPE protocol deviations were committed by doffing assistants and/or trained observers. Fluorescence was detected on 8 EVD PPE HCWs (44%) and 5 CP PPE HCWs (28%), most commonly on hands. MS2 was recovered from 2 EVD PPE HCWs (11%) and 3 CP PPE HCWs (17%).CONCLUSIONSProtocol deviations were common during both EVD and CP PPE doffing, and some deviations during EVD PPE doffing were committed by the HCW doffing assistant and/or the trained observer. Self-contamination was common. PPE donning/doffing are complex and deserve additional study.Infect Control Hosp Epidemiol 2017;38:1077–1083</jats:sec

Anaerobic performance testing of professional soccer players 1995-2010

Published version of an article from the journal: International Journal of Sports Physiology and Performance. Also available from Human Kinetics:http://journals.humankinetics.com/ijspp-back-issues/ijspp-volume-8-issue-2-march/anaerobic-performance-testing-of-professional-soccer-players-1995ndash2010Purpose: To compare sprint and countermovement-jump (CMJ) performance among competitive soccer players as a function of performance level, field position, and age. In addition, the authors wanted to quantify the evolution of these physical characteristics among professional players over a 15-y period. Methods: 939 athletes (22.1 +/- 4.3 y), including national-team players, tested 40-m sprint with electronic timing and CMJ on a force platform at the Norwegian Olympic Training Center between 1995 and 2010. Results: National-team and 1st-division players were faster (P<.05) than 2nd-division (1.0-1.4%), 3rd- to 5th-division (3.0-3.8%), junior national-team (1.7-2.2%), and junior players (2.8-3.7%). Forwards were faster than defenders (1.4%), midfielders (2.5%), and goalkeepers (3.2%) over 0-20 m (P<.001). Midfielders jumped similar to 2.0 cm lower than the other playing positions (P<.05). Sprinting velocity peaked in the age range 20-28 y and declined significantly thereafter (P<.05). Players from 2006-2010 had 1-2% faster 0-20 m and peak velocity than players from the 1995-1999 and 2000-2005 epochs, whereas no differences in CMJ performance were observed. Conclusions: This study provides effect-magnitude estimates for the influence of performance level, position, and age on sprint and CMJ performance in soccer. While CMJ performance has remained stable over the time, there has been a small but positive development in sprinting velocity among professional players