Sports activity patterns and cardio-metabolic health over time among adults in Germany: Results of a nationwide 12-year follow-up study

BackgroundPhysical activity is favorable for health, and vigorous sports activity is particularly beneficial. This study investigates the association between changes in sports participation patterns over time and cardio-metabolic and self-perceived health outcomes.MethodsData from 3752 adults (18–79 years of age) who participated in 2 national health interview and examination surveys in 1997–1999 and 2008–2011 were included, with a mean follow-up time of about 12 years. A change in self-reported sports activity was analyzed with respect to the incidence of type 2 diabetes, coronary heart disease (CHD), hypertension, obesity, dyslipidemia, metabolic syndrome, and poor self-perceived health. Participants with pre-existing disease or risk factor of interest at baseline were excluded from the analysis. Being sufficiently active in sports was specified as doing sports for at least 1–2 h per week, and 4 activity categories were defined: 1) inactive at both time points (inactive–inactive), 2) inactive at baseline and active at follow-up (inactive–active), 3) active at baseline and inactive at follow-up (active–inactive), and 4) active at both time points (active–active). Associations between sports activity engagement and health outcomes were estimated by logistic regression models with different stages of adjustments.ResultsNot engaging in any regular sports activity at both time points (inactive–inactive) was associated with higher rates of type 2 diabetes (odds ratio (OR) = 1.82, 95% confidence interval (95%CI): 1.08–3.08), CHD (OR = 1.82, 95%CI: 1.16–2.84), hypertension (OR = 1.36, 95%CI: 1.03–1.81), metabolic syndrome (OR = 1.58, 95%CI: 1.08–2.32), and poor self-perceived health (OR = 2.54, 95%CI: 1.83–3.53) compared to doing regular sports for a minimum of 1–2 h per week over time (active–active). In case of change from inactivity to any regular sports activity (inactive–active), the rate of risk factor occurrence was not statistically different from the active–active reference group except for poor self-perceived health, but it was higher for type 2 diabetes (OR = 2.15, 95%CI: 1.12–4.14) and CHD (OR = 1.77, 95%CI: 1.03–3.03). Being active at baseline but inactive at follow-up (active–inactive) was not associated with higher disease incidence of type 2 diabetes (OR = 0.70, 95%CI: 0.25–1.97) or CHD (OR = 1.20, 95%CI: 0.49–2.99), but was associated with higher rates of hypertension (OR = 1.61, 95%CI: 1.11–2.34), obesity (OR = 2.34, 95%CI: 1.53–3.57), metabolic syndrome (OR = 1.70, 95%CI: 1.11–2.63), and poor self-perceived health (OR = 2.16, 95%CI: 1.53–3.07) at follow-up.ConclusionEven a low weekly quantity (1–2 h) of regular sports activity is partly associated with health benefits. Being formerly but not currently active was not associated with an increased disease incidence, but was associated with a higher risk-factor development compared to the reference group (active–active). Becoming active was preventive for risk-factor development but was not preventive for disease incidence, which probably means that the health benefits from sports activity are not sustainable and disease incidence is only shifted to a later period in life. For this reason, the promotion of and commitment to regular sports activity should be addressed as early as possible over the lifespan to achieve the best health benefits.     

Neuromuscular,biochemical and perceptual post-match fatigue in professional rugby league forwards and backs

Abstract

In this study, we investigated changes in creatine kinase, perceptual and neuromuscular fatigue of professional rugby league players after match-play. Twenty-three male rugby league players (10 backs, 13 forwards) had their creatine kinase, perceptual ratings of fatigue, attitude to training, muscle soreness, and flight time in a countermovement jump measured before and 1 and 2 days after (day 1 and day 2 respectively) league matches. Total playing time, offensive and defensive contacts were also recorded for each player. Creatine kinase was higher both 1 and 2 days after than before matches (P < 0.05) in forwards and backs. Similarly, perceived fatigue and muscle soreness were higher than pre-match on both days 1 and 2 (P < 0.05), but did not differ between groups (P > 0.05). Jump performance was lower on day 1 but not day 2 for both groups (P < 0.05). While total playing time was longer in backs (P < 0.05), relative frequencies for all contacts were greater in forwards (P < 0.05). Contacts for forwards were correlated with all markers of fatigue (P < 0.05), but only flight time was correlated with offensive contacts in backs (P < 0.05). Despite the mechanisms of fatigue being different between forwards and backs, our results highlight the multidimensional nature of fatigue after a rugby league match and that these markers do not differ between positions.     

Pacing during a cross-country mountain bike mass-participation event according to race performance,experience, age and sex

This study describes pacing strategies adopted in an 86-km mass-participation cross-country marathon mountain bike race (the ‘Birkebeinerrittet’). Absolute (km·h^?1) and relative speed (% average race speed) and speed coefficient of variation (%CV) in five race sections (15.1, 31.4, 52.3, 74.4 and 100% of total distance) were calculated for 8182 participants. Data were grouped and analysed according to race performance, age, sex and race experience. The highest average speed was observed in males (21.8?±?3.7?km/h), 16–24?yr olds (23.0?±?4.8?km/h) and those that had previously completed >4 Birkebeinerrittet races (22.5?±?3.4?km/h). Independent of these factors, the fastest performers exhibited faster speeds across all race sections, whilst their relative speed was higher in early and late climbing sections (Cohen's d?=?0.45–1.15) and slower in the final descending race section (d?=?0.64–0.98). Similar trends were observed in the quicker age, sex and race experience groups, who tended to have a higher average speed in earlier race sections and a lower average speed during the final race section compared to slower groups. In all comparisons, faster groups also had a lower %CV for speed than slower groups (fastest %CV?=?24.02%, slowest %CV?=?32.03%), indicating a lower variation in speed across the race. Pacing in a cross-country mountain bike marathon is related to performance, age, sex and race experience. Better performance appears to be associated with higher relative speed during climbing sections, resulting in a more consistent overall race speed.     

Alterations to the orientation of the ground reaction force vector affect sprint acceleration performance in team sports athletes

A more horizontally oriented ground reaction force vector is related to higher levels of sprint acceleration performance across a range of athletes. However, the effects of acute experimental alterations to the force vector orientation within athletes are unknown. Fifteen male team sports athletes completed maximal effort 10-m accelerations in three conditions following different verbal instructions intended to manipulate the force vector orientation. Ground reaction forces (GRFs) were collected from the step nearest 5-m and stance leg kinematics at touchdown were also analysed to understand specific kinematic features of touchdown technique which may influence the consequent force vector orientation. Magnitude-based inferences were used to compare findings between conditions. There was a likely more horizontally oriented ground reaction force vector and a likely lower peak vertical force in the control condition compared with the experimental conditions. 10-m sprint time was very likely quickest in the control condition which confirmed the importance of force vector orientation for acceleration performance on a within-athlete basis. The stance leg kinematics revealed that a more horizontally oriented force vector during stance was preceded at touchdown by a likely more dorsiflexed ankle, a likely more flexed knee, and a possibly or likely greater hip extension velocity.     

Mindset × Context: Schools,Classrooms, and the Unequal Translation of Expectations into Math Achievement

When do adolescents' dreams of promising journeys through high school translate into academic success? This monograph reports the results of a collaborative effort among sociologists and psychologists to systematically examine the role of schools and classrooms in disrupting or facilitating the link between adolescents' expectations for success in math and their subsequent progress in the early high school math curriculum. Our primary focus was on gendered patterns of socioeconomic inequality in math and how they are tethered to the school's peer culture and to students' perceptions of gender stereotyping in the classroom. To do this, this monograph advances Mindset × Context Theory. This orients research on educational equity to the reciprocal influence between students' psychological motivations and their school-based opportunities to enact those motivations. Mindset × Context Theory predicts that a student's mindset will be more strongly linked to developmental outcomes among groups of students who are at risk for poor outcomes, but only in a school or classroom context where there is sufficient need and support for the mindset. Our application of this theory centers on expectations for success in high school math as a foundational belief for students' math progress early in high school. We examine how this mindset varies across interpersonal and cultural dynamics in schools and classrooms. Following this perspective, we ask:

• 1. Which gender and socioeconomic identity groups showed the weakest or strongest links between expectations for success in math and progress through the math curriculum?
• 2. How did the school's peer culture shape the links between student expectations for success in math and math progress across gender and socioeconomic identity groups?
• 3. How did perceptions of classroom gender stereotyping shape the links between student expectations for success in math and math progress across gender and socioeconomic identity groups?

We used nationally representative data from about 10,000 U.S. public school 9th graders in the National Study of Learning Mindsets (NSLM) collected in 2015–2016—the most recent, national, longitudinal study of adolescents' mindsets in U.S. public schools. The sample was representative with respect to a large number of observable characteristics, such as gender, race, ethnicity, English Language Learners (ELLs), free or reduced price lunch, poverty, food stamps, neighborhood income and labor market participation, and school curricular opportunities. This allowed for generalization to the U.S. public school population and for the systematic investigation of school- and classroom-level contextual factors. The NSLM's complete sampling of students within schools also allowed for a comparison of students from different gender and socioeconomic groups with the same expectations in the same educational contexts. To analyze these data, we used the Bayesian Causal Forest (BCF) algorithm, a best-in-class machine-learning method for discovering complex, replicable interaction effects. Chapter IV examined the interplay of expectations, gender, and socioeconomic status (SES; operationalized with maternal educational attainment). Adolescents' expectations for success in math were meaningful predictors of their early math progress, even when controlling for other psychological factors, prior achievement in math, and racial and ethnic identities. Boys from low-SES families were the most vulnerable identity group. They were over three times more likely to not make adequate progress in math from 9th to 10th grade relative to girls from high-SES families. Boys from low-SES families also benefited the most from their expectations for success in math. Overall, these results were consistent with Mindset × Context Theory's predictions. Chapters V and VI examined the moderating role of school-level and classroom-level factors in the patterns reported in Chapter IV. Expectations were least predictive of math progress in the highest-achieving schools and schools with the most academically oriented peer norms, that is, schools with the most formal and informal resources. School resources appeared to compensate for lower levels of expectations. Conversely, expectations most strongly predicted math progress in the low/medium-achieving schools with less academically oriented peers, especially for boys from low-SES families. This chapter aligns with aspects of Mindset × Context Theory. A context that was not already optimally supporting student success was where outcomes for vulnerable students depended the most on student expectations. Finally, perceptions of classroom stereotyping mattered. Perceptions of gender stereotyping predicted less progress in math, but expectations for success in math more strongly predicted progress in classrooms with high perceived stereotyping. Gender stereotyping interactions emerged for all sociodemographic groups except for boys from high-SES families. The findings across these three analytical chapters demonstrate the value of integrating psychological and sociological perspectives to capture multiple levels of schooling. It also drew on the contextual variability afforded by representative sampling and explored the interplay of lab-tested psychological processes (expectations) with field-developed levers of policy intervention (school contexts). This monograph also leverages developmental and ecological insights to identify which groups of students might profit from different efforts to improve educational equity, such as interventions to increase expectations for success in math, or school programs that improve the school or classroom cultures.