Glucocorticoids and physical performance: A systematic review with meta-analysis of randomized controlled trials.

Introduction: This systematic review with meta-analysis investigates the effect of glucocorticoids on maximal and submaximal performance in healthy subjects. Methods: We searched for randomised controlled trials investigating the effect of glucocorticoids on physical performance in Web of Science, Scopus, Medline, Embase and SportDiscus in March 2021. Risk of bias was assessed with the revised Cochrane Collaboration Risk of Bias Tool (RoB2). Data from random effect models are presented as standardized difference in mean (SDM) with 95% confidence interval. We included 15 studies comprising 175 subjects. Results: Two studies had high risk of bias. Glucocorticoids had a small positive effect on maximal physical performance compared to placebo (SDM 0.300, 95% CI 0.080 to 0.520) and the SDM for the 13 included comparisons was not heterogeneous (I2 = 35%, p = 0.099). Meta regression found no difference in the effect of acute treatment vs. prolonged treatment or oral ingestion vs. inhalation (p > 0.124). In stratified analysis prolonged treatment (SDM 0.428, 95% CI 0.148 to 0.709) and oral ingestion (SDM 0.361, 95% CI 0.124 to 0.598) improved physical performance. Glucocorticoids improved aerobic performance (SDM 0.371, 95% CI 0.173 to 0.569) but not anaerobic performance (p = 0.135). Glucocorticoids did not change energy expenditure during submaximal performance (SDM 0.0.225 95% CI -0.771 to 0.112). Discussion: This study indicates that glucocorticoids improves maximal performance and aerobic performance. Glucocorticoids did not affect the energy expenditure during submaximal performance. The conclusions are based on relatively few subjects leading to limited statistical power and uncertain estimates. Still, these results are consistent and should be of interest to WADA and anyone concerned about fair play. Systematic Review Registration: Open Science Framework 2021-04-29 (https://osf.io/fc29t/).

Effects of climbing- and resistance-training on climbing-specific performance: a systematic review and meta-analysis.

The objective of this systematic review and meta-analysis was to examine the effects of climbing and climbing-and-resistance-training on climbing performance, and strength and endurance tests. We systematically searched three databases (SPORTDiscus, SCOPUS, and PubMed) for records published until January 2021. The search was limited to randomized-controlled trials using active climbers and measuring climbing performance or performance in climbing-specific tests. Data from the meta-analysis are presented as standardized difference in mean (SDM) with 95% confidence intervals (95% CI). Eleven studies are included in the systematic review and five studies compared training to a control group and could be meta-analyzed. The overall meta-analysis displayed an improvement in climbing-related test performance following climbing-specific resistance training compared to only climbing (SDM = 0.57, 95%CI = 0.24-0.91). Further analyses revealed that finger strength (SDM = 0.41, 95%CI 0.03-0.80), rate of force development (SDM = 0.91, 95%CI = 0.21-1.61), and forearm endurance (SDM = 1.23, 95%CI = 0.69-1.77) were improved by resistance-training of the finger flexors compared to climbing training. The systematic review showed that climbing performance may be improved by specific resistance-training or interval-style bouldering. However, resistance-training of the finger flexors showed no improvements in strength or endurance in climbing-specific tests. The available evidence suggests that resistance-training may be more effective than just climbing-training for improving performance outcomes. Importantly, interventional studies including climbers is limited and more research is needed to confirm these findings.

E-cycling and health benefits: A systematic literature review with meta-analyses.

The objective of the present study is to review and meta-analyze the effect of E-cycling on health outcomes. We included longitudinal experimental and cohort studies investigating the effect of E-cycling on health outcomes. The studies were identified from the seven electronic databases: Web of Science, Scopus, Medline, Embase, PsycINFO, Cinahl and SportDiscus and risk of bias was assessed with the revised Cochrane Collaboration Risk of Bias Tool (RoB2). We performed meta-analysis with random effects models on outcomes presented in more than one study. Our study includes one randomized controlled trial, five quasi experimental trials and two longitudinal cohort studies. The trials included 214 subjects of whom 77 were included in control groups, and the cohort studies included 10,222 respondents at baseline. Maximal oxygen consumption and maximal power output were assessed in four and tree trials including 78 and 57 subjects, respectively. E-cycling increased maximal oxygen consumption and maximal power output with 0.48 SMD (95%CI 0.16-0.80) and 0.62 SMD (95%CI 0.24-0.99). One trial reported a decrease in 2-h post plasma glucoses from 5.53 ± 1.18 to 5.03 ± 0.91 mmol L-1 and one cohort study reported that obese respondents performed 0.21 times more trips on E-bike than respondents with normal weight. All the included studies had a high risk of bias due to flaws in randomization. However, the outcomes investigated in most studies showed that E-cycling can improve health.

Associations between biological maturity level, match locomotion, and physical capacities in youth male soccer players.

INTRODUCTION: Biological maturity level has shown to affect sport performance in youths. However, most previous studies have used noninvasive methods to estimate maturity level. Thus, the main aim of the present study was to investigate the association between skeletal age (SA) as a measure of biological maturation level, match locomotion, and physical capacity in male youth soccer players. METHOD: Thirty-eight Norwegian players were followed during two consecutive seasons (U14 and U15). Match locomotion was assessed with GPS-tracking in matches. SA, assessed by x-ray, physical capacities (speed, strength and endurance) and anthropometrics were measured in the middle of each season. Analysis of associations between SA, match locomotion, and physical capacities were adjusted for the potential confounding effect of body height and weight. RESULTS: In matches, positive associations were found between SA and maximal speed and running distance in the highest speed zones. Further, SA was associated with 40 m sprint time and countermovement jump (CMJ) height, and with intermittent-endurance capacity after adjusting for body height (U14). Associations between SA and leg strength and power, and between SA and absolute VO2max were not significant after adjusting for body weight. There was no association between SA and total distance covered in matches. CONCLUSION: Biological maturity level influence match locomotion and performance on physical capacity tests. It is important that players, parents and coaches are aware of the advantages more mature players have during puberty, and that less mature players also are given attention, appropriate training and match competition to ensure proper development.

Motion Analysis of Match Play in U14 Male Soccer Players and the Influence of Position, Competitive Level and Contextual Variables.

This study aimed to investigate match running performance in U14 male soccer players in Norway, and the influence of position, competitive level and contextual factors on running performance. Locomotion was monitored in 64 different U14 players during 23 official matches. Matches were played at two different competitive levels: U14 elite level (n = 7) and U14 sub-elite level (n = 16). The inclusion criterion was completed match halves played in the same playing position. The variables' influence on match running performance was assessed using mixed-effect models, pairwise comparisons with Bonferroni correction, and effect size. The results showed that the U14 players, on average, moved 7645 ± 840 m during a match, of which 1730 ± 681 m (22.6%) included high-intensity running (HIR, 13.5-18.5 km·h-1) and sprinting (>18.5 km·h-1). Wide midfielders (WM) and fullbacks (FB) covered the greatest sprint distance (569 ± 40 m) and, in addition to the centre midfield position (CM), also covered the greatest total distance (TD) (8014 ± 140 m) and HIR distance (1446 ± 64 m). Centre forwards (CF) performed significantly more accelerations (49.5 ± 3.8) compared other positions. TD (7952 ± 120 m vs. 7590 ± 94 m) and HIR (1432 ± 57 m vs. 1236 ± 43 m) were greater in U14 elite-level matches compared with sub-elite matches. Greater TD and sprint distances were performed in home matches, but, on the other hand, more accelerations and decelerations were performed in matches played away or in neutral locations. Significantly higher TD, HIR and sprinting distances were also found in lost or drawn matches. In conclusion, physical performance during matches is highly related to playing position, and wide positions seem to be the most physically demanding. Further, competitive level and contextual match variables are associated with players' running performance.

National Trends in Cycling in Light of the Norwegian Bike Traffic Index.

National and international strategies and recommendations are intended to increase physical activity in the general population. Active transportation is included in interdisciplinary strategies to meet these recommendations. Cycling seems to be more health enhancing than walking for transportation since cycling seems to reduce the risk of cardiovascular disease and associated risk factors. Furthermore, the health benefits of cycling are proven to outrun the risk of injuries and mortality. Politicians seem to approve costly infrastructure strategies to increase the amount of cycling in the population to improve public health and shift to more sustainable travel habits. A linear relationship between cycle-friendly infrastructure and the amount of commuter cycling has been demonstrated. However, in Norway and on a global level, there is a lack of robust evaluations of actions and sensitive monitoring systems to observe possible change. Therefore, we aimed to develop the Norwegian bike traffic index and describe the national, regional, and local trends in counted cycle trips. We used a transparent methodology so that the index can be used, developed, and adapted in other countries. We included 89 stationary counters from the whole country. Counters monitored cycling from 2018 onward. The index is organized at local, regional, and national levels. Furthermore, the index is adjusted for population density at the counter level and presented as ratio of counted cycle trips, comparing 2018 to subsequent years. The index is presented as a percentage change with 95% confidence intervals. In Norway, counted cycle trips increased by 11% from 2018 (100, 100-100) to 2020 (111.0, 106.2-115.1), with large geographical differences. In Southern Norway, there was a significant increase of 23%, and in Northern Norway, there was a nonsignificant decrease by 8% from 2018 to 2020. The indices may indicate possible related effects of local to national cycling strategies and how the COVID-19 pandemic has affected Norwegian travel habits in urban areas.

Validation of a Modified Submaximal Balke Protocol to Assess Cardiorespiratory Fitness in Individuals at High Risk of or With Chronic Health Conditions-A Pilot Study.

Objectives: This study aims to validate a submaximal treadmill walking test for estimation of maximal oxygen consumption (VO2max) in individuals at high risk of or with chronic health conditions. Method: Eighteen participants (age 62 ± 16 years; VO2max 31.2 ± 5.9 ml kg-1 min-1) at high risk of getting or with established chronic diseases performed two valid modified Balke treadmill walking protocols, one submaximal protocol, and one maximal protocol. Test duration, heart rate (HR), and rate of perceived exertion (RPE) were measured during both tests. VO2max was measured during the maximal test. VO2max was estimated from the submaximal test by multiple regression using time to RPE ≥ 17, gender, age, and body mass as independent variables. Model fit was reported as explained variance (R 2) and standard error of the estimate (SEE). Results: The model fit for estimation of VO2max from time to RPE ≥ 17 at the submaximal test, body mass, age, and gender was R 2 = 0.78 (SEE = 3.1 ml kg-1 min-1, p ≤ 0.001). Including heart rate measurement did not improve the model fit. Conclusions: The submaximal walking test is feasible and valid for assessing cardiorespiratory fitness in individuals with high risk of or chronic health conditions.

Longitudinal changes in maximal oxygen uptake in adolescent girls and boys with different training backgrounds.

The purpose of this study was to investigate the effects of high-volume endurance training on the development of maximal oxygen uptake (VO2max ) in physically active boys and girls between the ages of 12 and 15 years, using a longitudinal design. The children participated in organized training in sports clubs for an average of 7-10 hours per week, with one group undertaking a high volume of endurance training (~7 hours per week; End boys, n = 23 and End girls, n = 17) and the other group having a primary focus on technical and tactical skill development, undertaking low volumes of endurance training (~1.6 hours per week; non-End boys, n = 29 and non-End girls, n = 9). VO2max and anthropometrics were assessed at age 12, 13, and 15. At age 12, VO2max was 58.9 (5.6), 65.5 (7.2), 56.5 (6.5), and 58.8 (7.9) mL·kg-1 ·min-1 in End girls, End boys, non-End girls, and non-End boys, respectively. Over the three years, there was no difference between the training groups in the development of VO2max independent of scaling. In boys, VO2max relative to body mass (BM) did not change from age 12 to 15, while VO2max tended to decrease relative to fat-free mass (FFM). In girls, VO2max relative to BM decreased slightly from age 12 to 15, with no changes over the years relative to FFM. The present longitudinal study suggests that in growing active children during puberty, high volumes of systematic endurance training do not have an additional effect on VO2max compared with similar volume of training mainly aiming at developing motor skills.

Aerobic performance among healthy (non-asthmatic) adults using beta2-agonists: a systematic review and meta-analysis of randomised controlled trials.

OBJECTIVE: To examine the effect of beta2-agonists on aerobic performance in healthy, non-asthmatic study participants. DESIGN: Systematic review and meta-analysis. ELIGIBILITY CRITERIA: We searched four databases (PubMed, Embase, SPORTDiscus and Web of Science) for randomised controlled trials published until December 2019. Studies examining the effect of beta2-agonists on maximal physical performance lasting longer than 1 min were included in the meta-analysis. Data are presented as standardised difference in mean (SDM) with 95% CI. RESULTS: The present meta-analysis includes 47 studies. The studies comprise 607 participants in cross-over trials, including 99 participants in three-way cross-over trials and 27 participants in a four-way cross-over trial. Seventy-three participants were included in parallel trials. Beta2-agonists did not affect aerobic performance compared with placebo (SDM 0.051, 95% CI -0.020 to 0.122). The SDM for the included studies was not heterogeneous (I2=0%, p=0.893), and the effect was not related to type of beta2-agonist, dose, administration route, duration of treatment or performance level of participants. Beta2-agonists had no effect on time trial performance, time to exhaustion or maximal oxygen consumption (p<0.218). CONCLUSION/IMPLICATION: The present study shows that beta2-agonists do not affect aerobic performance in non-asthmatic subjects regardless of type, dose, administration route, duration of treatment or performance level of participants. The results of the present study should be of interest to WADA and to anyone who is interested in equal opportunities in competitive sports. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018109223.

Can ß2-agonists have an ergogenic effect on strength, sprint or power performance? Systematic review and meta-analysis of RCTs.

OBJECTIVES: We aimed to examine the effect of ß2-agonists on anaerobic performance in healthy non-asthmatic subjects. DESIGN: Systematic review and meta-analysis. ELIGIBILITY CRITERIA: We searched four databases (PubMed, Embase, SPORTDiscus and Web of Science) for randomised controlled trials, published until December 2019, examining the effect of ß2-agonists on maximal physical performance lasting 1 min or shorter. Data are presented as standardised difference in mean (SDM) with 95% confidence intervals (95% CI). RESULTS: 34 studies were included in the present meta-analysis. The studies include 44 different randomised and placebo-controlled comparisons with ß2-agonists comprising 323 participants in crossover trials, and 149 participants in parallel trials. In the overall analyses, ß2-agonists improved anaerobic performance by 5% (SDM 0.29, 95% CI 0.16 to 0.42), but the effect was related to dose and administration route. In a stratified analysis, the SDM was 0.14 (95% CI 0.00 to 0.28) for approved ß2-agonists and 0.46 (95% CI 0.24 to 0.68) for prohibited ß2-agonists, respectively. Furthermore, SDM was 0.16 (95% CI 0.02 to 0.30) for inhaled administration and 0.51 (95% CI 0.25 to 0.77) for oral administration, respectively, and 0.20 (95% CI 0.07 to 0.33) for acute treatment and 0.50 (95% CI 0.20 to 0.80) for treatment for multiple weeks. Analyses stratified for the type of performance showed that strength (0.35, 95% CI 0.15 to 0.55) and sprint (0.17, 95% CI 0.06 to 0.29) performance were improved by ß2-agonists. CONCLUSION/IMPLICATION: Our study shows that non-asthmatic subjects can improve sprint and strength performance by using ß2-agonists. It is uncertain, however, whether World Anti-Doping Agency (WADA)-approved doses of ß2-agonists improve performance. Our results support that the use of ß2-agonists should be controlled and restricted to athletes with documented asthma. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42018109223.

Correlates of Commuter Cycling in Three Norwegian Counties.

Globally, there is an increasing challenge of physical inactivity and associated diseases. Commuter cycling is an everyday physical activity with great potential to increase the health status in a population. We aimed to evaluate the association of self-reported factors and objectively measured environmental factors in residence and along commuter routes and assessed the probability of being a commuter cyclist in Norway. Our study included respondents from a web-based survey in three Norwegian counties and we used a Geographic Information Systems (GIS) to evaluate the natural and built environment. Of the 1196 respondents, 488 were classified as commuter cyclists. Self-reported factors as having access to an e-bike (OR 5.99 [CI: 3.71-9.69]), being physically active (OR 2.56 [CI: 1.42-4.60]) and good self-rated health (OR 1.92 [CI: 1.20-3.07]) increased the probability of being a cyclist, while being overweight or obese (OR 0.71 [CI: 0.54-0.94]) reduced the probability. Environmental factors, such as high population density (OR 1.49 [CI: 1.05-2.12]) increased the probability, while higher slope (trend p = 0.020), total elevation along commuter route (trend p = 0.001), and >5 km between home and work (OR 0.17 [CI: 0.13-0.23]) decreased the probability of being a cyclist. In the present study, both self-reported and environmental factors were associated with being a cyclist. With the exception of being in good health, the characteristics of cyclists in Norway, a country with a low share of cyclists, seem to be similar to countries with a higher share of cyclists. With better knowledge about characteristics of cyclists, we may design better interventions and campaigns to increase the share of commuter cyclists.

Match Running Performance on Three Different Competitive Standards in Norwegian Soccer.

The aim of the study was to compare running performance of three competitive standards and to examine the effects of being promoted to a higher league in Norwegian football. One club's first and second team were included. The first team consisted of professional soccer players playing at Level 2 (2015 season) and Level 1 (2016 season). The second team consisted of amateurs playing at Level 4. A fully automatic tracking system was used to examine running performance, divided into different running-speed categories and playing position. Forty-one matches were included containing 278 observations. Level 1 performed 61 and 51% sprinting compared to Level 2 and Level 4 but similar high-speed running. Similar high-speed running distances were observed only for the different playing positions at Level 1 compared to Level 2 and 4. The sprinting distance was greater for the central defender and attacker, and the number of accelerations was greater for central midfielders and wide midfielders' playing at Level 1 compared to lower competitive standards. In conclusion, better competitive standards resulted in greater high-intensity actions than lower leagues in Norwegian soccer. Furthermore, only central defenders and attackers increased their high-intensity locomotions when the team was promoted.

Running Performance and Position is Not Related to Decision-Making Accuracy in Referees.

We aimed to assess if running performance is related to decision-making accuracy in referees. We also investigated the relationships between movement, position, decision-making and time of infringement. The study included 347 free kicks and penalties awarded during all 15 home field matches for one team in the Norwegian top league. Movement and position were measured by a radio-based positioning system, and two external experts analysed the video clips. The referees made the correct decision in 98% of the assessed foul situations. There were no associations between the correctness and running speed at the time of the infringements or total distance accumulated during the 30 s prior to the infringement (p>0.08). Decision-making accuracy was not associated with the referees' position in relation to the infringements (p=0.82) or the area where the infringements occurred (p=0.28). Most foul play incidents were sanctioned in the central area of the field (84%) where the distance to the infringements was shorter (13.4 m, 95% CI 12.8-14.0) than in the lateral areas (21.9 m, 95% CI 20.4-23.4). Norwegian top referees were practically always right when they interfered, possess the necessary fitness to avoid fatigue that would influence decision-making accuracy, and maintain adequate positional ability throughout the matches.

Cycling is associated with a lower incidence of cardiovascular diseases and death: Part 1 - systematic review of cohort studies with meta-analysis.

OBJECTIVES: Physical inactivity is a risk factor for cardiovascular disease (CVD). Cycling as a physical activity holds great potential to prevent CVD. We aimed to determine whether cycling reduces the risk of CVD and CVD risk factors and to investigate potential dose-response relationships. DESIGN: Systematic review and meta-analysis of quantitative studies. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: We searched four databases (Web of Science, MEDLINE, SPORTDiscus and Scopus). All quantitative studies, published until August 2017, were included when a general population was investigated, cycling was assessed either in total or as a transportation mode, and CVD incidence, mortality or risk factors were reported. Studies were excluded when they reported continuous outcomes or when cycling and walking were combined in them. We pooled adjusted relative risks (RR) and OR. Heterogeneity was investigated using I. RESULTS: The search yielded 5174 studies; 21 studies which included 1,069,034 individuals. We found a significantly lower association in combined CVD incidence, mortality and physiological risk factors with total effect estimate 0.78 (95% CI (CI): 0.74-0.82; P<0.001; I2=58%). Separate analyses for CVD incidence, mortality and risk factors showed estimates of RR 0.84 (CI, 0.80 to 0.88; P<0.001; I2=29%), RR 0.83 (CI, 0.76 to 0.90; P<0.001; I2=0%), and OR 0.75 (CI, 0.69 to 0.82; P<0.001; I2=66%), respectively. We found no dose-response relationship or sex-specific difference. CONCLUSIONS: Any form of cycling seems to be associated with lower CVD risk, and thus, we recommend cycling as a health-enhancing physical activity. SYSTEMATIC REVIEW REGISTRATION: Prospero CRD42016052421.

Cycling and cardiovascular disease risk factors including body composition, blood lipids and cardiorespiratory fitness analysed as continuous variables: Part 2-systematic review with meta-analysis.

OBJECTIVES: We aimed to examine the relationship between cycling (particularly commuter cycling) and risk factors associated with cardiovascular diseases (CVDs) including body composition, blood lipids and cardiorespiratory fitness. This study differed from our recent (Part 1) systematic review in that risk factors for CVD were analysed as continuous variables rather than being present or absent. DESIGN: Systematic review and meta-analysis. ELIGIBILITY CRITERIA: We searched four databases (Web of Science, MEDLINE, SPORTDiscus and Scopus). All quantitative studies, published until August 2017, were included when a general population was investigated, cycling was assessed either in total or as a transportation mode, and CVD risk factors were reported. METHODS: We analysed body composition, physical activity (PA), cardiorespiratory fitness (CRF), blood lipids and blood pressure (BP). Skinfold, waist circumference and body mass index were analysed and prioritised in that order when more than one measure were available. PA included measures of counts per minutes, moderate-to-vigorous PA or minutes per week. CRF included results of maximal tests with or without expired air or submaximal test. For blood lipids and BP, separate analyses were run for low-density and high-density lipoprotein, triglycerides, total cholesterol, systolic BP and diastolic BP. Studies were excluded when reporting dichotomous outcomes or when cycling and walking were combined. Heterogeneity was investigated using I2. RESULTS: Fifteen studies were included; the majority reported commuter cycling. In total, we included 5775 cyclists and 39 273 non-cyclists. Cyclists had more favourable risk factor levels in body composition -0.08 (95% CI -0.13 to -0.04), PA 0.13 (95% CI 0.06 to 0.20), CRF 0.28 (95% CI 0.22 to 0.35) and blood lipids compared with non-cyclists. There was no sex difference in risk reduction. CONCLUSION/IMPLICATION: Cycling mitigated the risk factor profile for CVD. A strength of this systematic review is that all the risk factors were analysed as continuous variables. These data provide evidence for practitioners, stakeholders, policy-makers and city planners to accommodate and promote cycling. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016052421.

Public employees in South-Western Norway using an e-bike or a regular bike for commuting - A cross-sectional comparison on sociodemographic factors, commuting frequency and commuting distance.

Large-scale analyses on the travel behavior of e-bikes are scarce, and current knowledge regarding who the e-bike owners are is inconsistent. Also, commuters represent a relevant user group with an unexploited potential. Therefore, the purpose of the present study was to examine (i) associations between type of bike (e-bike vs. regular bike) with place of residence (county), sociodemographic variables (age, sex, educational level, income and ethnicity) and habitual physical activity level, and (ii) if public employees possessing an e-bike cycle more often and longer distances to work. A cross-sectional survey was conducted in 2017 among 1977 (5.2% of eligible subjects) public employees in Southern and Western Norway. Binary and multinomial logistic regression analyses were conducted. Respondents possessing an e-bike were less likely to perform high levels of leisure time physical activity (OR 0.56 (CI 0.39-0.82)), compared to those possessing a regular bike only. For those residing in Agder, the likelihood of possessing an e-bike (vs. regular bike) was almost 4 times higher (OR 3.98 (CI 2.53-6.26)), compared with participants residing in Sogn og Fjordane. Compared with those possessing a regular bike only, e-bike users cycled more frequently to work, both occasionally (OR 3.71 (CI 2.44-5.65)) and most of the time (OR 4.28 (CI 2.79-6.55)), and they had higher odds of cycling medium distances to the workplace (OR 1.74 (CI 1.04-2.90)). In conclusion, e-bike access could result in increased commuter cycling, both in terms of cycling frequency and cycling distance, which in turn could contribute to enhanced physical activity levels.

The Construct Validity of the CODA and Repeated Sprint Ability Tests in Football Referees.

As of 2017, the international football federation introduced the change of direction ability test (CODA) and the 5×30 m sprint test for assistant referees (ARs) and continued the 6×40 m sprint test for field referees (FRs) as mandatory tests. The aim of this study was to evaluate the association between performance in these tests and running performance during matches at the top level in Norway. The study included 9 FRs refereeing 21 matches and 19 ARs observed 53 times by a local positioning system at three stadiums during the 2016 season. Running performance during matches was assessed by high-intensity running (HIR) distance, HIR counts, acceleration distance, and acceleration counts. For the ARs, there was no association between the CODA test with high-intensity running or acceleration (P>0.05). However, the 5×30 m sprint test was associated with HIR count during the entire match (E -12.9, 95% CI -25.4 to -0.4) and the 5-min period with the highest HIR count (E -2.02, 95% CI -3.55 to -0.49). For the FRs, the 6×40 m fitness test was not associated with running performance during matches (P>0.05). In conclusion, performance in these tests had weak or no associations with accelerations or HIR in top Norwegian referees during match play.

Promoting workplace stair climbing: sometimes, not interfering is the best.

BACKGROUND: Stair climbing is a vigorous activity and can lead to several health benefits. Studies seeking to increase stair climbing in various public locations have shown positive effects, while results from similar studies conducted in the workplace are inconclusive. This study examined stair climbing in the workplace, and monitored effects from a single- and a combined intervention. Interventions were inspired by nudging, the libertarian method of influencing behavior. METHODS: By quasi-experimental design, stair- and elevator traffic in two office buildings was monitored preceding-, during- and following interventions with stair leading footprints alone, and combined with stair-riser banners. Chi square tests were applied to determine differences between baseline and the subsequent periods. Web-based questionnaires were distributed after follow-up period. RESULTS: Elevators and stairs were used 45 237 times, of which 89.6% was stair use. Intervention site stair climbing at baseline (79.0%) was significantly reduced with footprints (-5.1%, p < 0.001), and footprints with stair-riser banners (-5.7%, p < 0.001) while baseline stair climbing at the control site (94.2%) remained stable (p > 0.027). CONCLUSIONS: Stair climbing was significantly reduced during the intervention periods. Use of stair leading footprints alone, or combined with stair-riser banners in an attempt to influence stair climbing may be ineffective, or cause a negative reaction, when applied in a workplace with a pre-existing high amount of stair climbing.

The human microbiome, asthma, and allergy.

The human microbiome can be defined as the microorganisms that reside within and on our bodies and how they interact with the environment. Recent research suggests that numerous mutually beneficial interactions occur between a human and their microbiome, including those that are essential for good health. Modern microbiological detection techniques have contributed to new knowledge about microorganisms in their human environment. These findings reveal that the microbiomes of the lung and gut contribute to the pathogenesis of asthma and allergy. For example, evidence indicates that the microbiome of the gut regulates the activities of helper T cell subsets (Th1 and Th2) that affect the development of immune tolerance. Moreover, recent studies demonstrate differences between the lung microbiomes of healthy and asthmatic subjects. The hygiene and biodiversity hypotheses explain how exposure to microorganisms is associated with asthma and allergy. Although those living in developed countries are exposed to fewer and less diverse microorganisms compared with the inhabitants of developing countries, they are experiencing an increase in the incidence of asthma and allergies. Detailed analyses of the human microbiome, as are being conducted under the auspices of the Human Microbiome Project initiated in 2007, promise to contribute insights into the mechanisms and factors that cause asthma and allergy that may lead to the development of strategies to prevent and treat these diseases.