ResearchPad - sports-science https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Relationship between maximal incremental and high-intensity interval exercise performance in elite athletes]]> https://www.researchpad.co/article/elastic_article_13822 This descriptive study aimed to explore the physiological factors that determine tolerance to exertion during high-intensity interval effort. Forty-seven young women (15–28 years old) were enrolled: 23 athletes from Taiwan national or national reserve teams and 24 moderately active females. Each participant underwent a maximal incremental INC (modified Bruce protocol) cardiopulmonary exercise test on the first day and high-intensity interval testing (HIIT) on the second day, both performed on a treadmill. The HIIT protocol involved alternation between 1-min effort at 120% of the maximal speed, at the same slope reached at the end of the INC, and 1-min rest until volitional exhaustion. Gas exchange, heart rate (HR), and muscle oxygenation at the right vastus lateralis, measured by near-infrared spectroscopy, were continuously recorded. The number of repetitions completed (Rlim) by each participant was considered the HIIT tolerance index. The results showed a large difference in the Rlim (range, 2.6–12.0 repetitions) among the participants. Stepwise linear regression revealed that the variance in the Rlim within the cohort was related to the recovery rates of oxygen consumption (V˙O2), HR at the second minute after INC, and muscle tissue saturation index at exhaustion (R = 0.644). In addition, age was linearly correlated with Rlim (adjusted R = −0.518, p < 0.0001). In conclusion, the recovery rates for V˙O2 and HR after the incremental test, and muscle saturation index at exhaustion, were the major physiological factors related to HIIT performance. These findings provide insights into the role of the recovery phase after maximal INC exercise testing. Future research investigating a combination of INC and HIIT testing to determine training-induced performance improvement is warranted.

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<![CDATA[A descriptive cross sectional study comparing barriers and determinants of physical activity of Sri Lankan middle aged and older adults]]> https://www.researchpad.co/article/elastic_article_7830 Benefits of physical activities are numerous. Barriers for physical exercise may differ among middle aged and older adults. Therefore, identifying and comparing the barriers for participating in regular physical exercises among middle aged and older adults will be useful in designing age specific physical exercise programmes.MethodsThis descriptive cross sectional study was carried out among 206 Sri Lankan adults in the age range of 40–84 years in the Colombo North region of Sri Lanka using culturally validated questionnaires to determine and compare the barriers and factors associated with regular physical activity participation. Majority were males (56%) and 54% were < 60 years. People in the age range of 40–59 years were considered as middle age and ≥ 60 years as older adults. Bivariate analysis and multivariate analysis was carried out to determine the significant factors that are associated with regular physical activity participation.ResultsLack of free time (52%), feeling too lazy (26%) and bad weather (29%) were the main barriers for the participants. In < 60 years, high level of income (p = 0.008) and in ≥ 60 years, being a male (p = 0.016), having a high level of education (P = 0.002) and a high BMI (p = 0.002) had a significant negative association with the level of physical activities.ConclusionsContrary to findings from surveys in several developed countries, this study showed that having a high level of education and being a male were strongly related with lack of physical activity participation. ]]> <![CDATA[Association between attending exercise-based cardiac rehabilitation and cardiovascular risk factors at one-year post myocardial infarction]]> https://www.researchpad.co/article/elastic_article_7688 Randomized trials confirm the benefits of exercise-based cardiac rehabilitation on cardiovascular risk factors. Whether exercise-based cardiac rehabilitation provides the same favourable effects in real-life cardiac rehabilitation settings, in the modern era of myocardial infarction treatment, is less well known. We examined the association between attending exercise-based cardiac rehabilitation and improvements in cardiovascular risk factors at one-year post myocardial infarction in patients included in the Swedish heart disease registry, SWEDEHEART.MethodsIn this retrospective registry-based cohort study, we included 19 136 patients post myocardial infarction (75% men, 62.8±8.7 years) who were registered in SWEDEHEART between 2011 and 2013. The association between attending exercise-based cardiac rehabilitation (43% participation rate) and changes in cardiovascular risk profile between baseline and one-year follow-up was assessed using multivariable regression analysis adjusting for age, comorbidities and medication.ResultsAttenders more often reported to have stopped smoking (men 64% vs 50%; women 64% vs 53%, p<0.001 for both, only smokers at baseline considered), be more physically active (men 3.9±2.5 vs 3.4±2.7 days/week; women 3.8±2.6 vs 3.0±2.8 days/week, p<0.001 for both) and achieved a slightly larger reduction in triglycerides (men -0.2±0.8 vs -0.1±0.9 mmol/L, p = 0.001; women -0.1±0.6 vs 0.0±0.8 mmol/L, p = 0.01) at one-year compared to non-attenders. Male attenders gained less weight (+0.0±5.7 vs +0.3±5.7 kg, p = 0.01) while female attenders achieved better lipid control (total cholesterol -1.2±1.4 vs -0.9±1.4 mmol/L, p<0.001; low-density lipoprotein -1.2±1.2 vs -0.9 ±1.2 mmol/L, p<0.001) compared to non-attenders.ConclusionsIn an unselected registry cohort of patients post myocardial infarction, compared to non-attenders those attending exercise-based cardiac rehabilitation achieved significantly larger improvements in cardiovascular risk factors at one-year after the acute event. ]]> <![CDATA[The relationship of recreational runners’ motivation and resilience levels to the incidence of injury: A mediation model]]> https://www.researchpad.co/article/elastic_article_7663 Running participation has increased significantly in the last decade. Despite its association with different health-related aspects, athletes may experience adverse outcomes, including injuries. The aim of this study was twofold: to examine the relationship between runners’ resilience levels, motivation and incidence of injury, on the one hand; and to analyse the mediation that intrinsic and extrinsic motivation has on the association between the number of injuries and psychological resilience levels among amateur athletes. The sample consisted of a total of 1725 runners (age: 40.40 ± 9.39 years), 1261 of whom were male (age: 43.16 ± 9.38), and 465 of whom were female (age: 40.34 ± 9.14). Athletes completed the Behavioural Regulation in Exercise Questionnaire (BREQ-3), the Resilience scale (CD-RISC 10), and an Injury retrospective survey. Three mediation models were constructed, and the results showed a significant indirect association of athletes’ intrinsic motivation and resilience on the number of injuries (β = 0.022, CI = 0.007, 0.0) in mediation model 1, whereas extrinsic motivation was found to have no significant association on those variables (β = -0.062, CI = -0.137, 0.009) in mediation model 2. Model 3 showed significant differences with respect to resilience (p < 0.05) and intrinsic motivation (p < 0.05). Therefore, the mediation of intrinsic motivation on athletes’ resilience levels and incidence of injury was demonstrated, i.e., it was found that intrinsic motivation was associated with a higher incidence of injury, while no such correlation was found for extrinsic motivation. This study shows that the amateur long distance runners with a high level of intrinsic motivation tend to suffer from a greater number of injuries, and at the same time psychological resilience was associated with a lower number of injuries.

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<![CDATA[‘In search of lost time’: Identifying the causative role of cumulative competition load and competition time-loss in professional tennis using a structural nested mean model]]> https://www.researchpad.co/article/N4f3da08e-598e-44d5-a4f3-a2c64fcebd1f

Injury prevention is critical to the achievement of peak performance in elite sport. For professional tennis players, the topic of injury prevention has gained even greater importance in recent years as multiple of the best male players have been sidelined owing to injury. Identifying potential causative factors of injury is essential for the development of effective prevention strategies, yet such research is hampered by incomplete data, the complexity of injury etiology, and observational study biases. The present study attempts to address these challenges by focusing on competition load and time-loss to competition—a completely observable risk factor and outcome—and using a structural nested mean model (SNMM) to identify the potential causal role of cumulative competition load on the risk of time-loss. Using inverse probability of treatment weights to balance exposure histories with respect to player ability, past injury, and consecutive competition weeks at each time point; the SNMM analysis of 389 professional male players and 55,773 weeks of competition found that total load significantly increases the risk of time-loss (HR = 1.05 per 1,000 games of additional load 95% CI 1.01-1.10) and this effect becomes magnified with age. Standard regression showed a protective effect of load, highlighting the value of more robust causal methods in the study of dynamic exposures and injury in sport and the need for further applications of these methods for understanding how time-loss and injuries of elite athletes might be prevented in the future.

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<![CDATA[Prevalence of depressive symptoms among Italian medical students: The multicentre cross-sectional “PRIMES” study]]> https://www.researchpad.co/article/N89095419-220d-4d38-944c-d00bb778cf6f

Background

Four percent of the world’s population suffers from depression, which is a major public health issue. Medical students are at risk, as their depressive symptoms (DS) prevalence is reported to be approximately 27% worldwide. Since few data on Italian medical students exist, this study aimed to estimate their DS prevalence and assess risk and protective factors.

Methods

The PRIMES was a multicentre cross-sectional study performed in 12 Italian medical schools. Questionnaires were self-reported and included 30 sociodemographic items and the Beck Depression Inventory-II (BDI-II). The primary outcome was the presence of DS (BDI-II score≥14). The main analyses were chi-squared tests and multivariable logistic regressions with a p-value<0.05 considered significant.

Results

The number of collected questionnaires was 2,513 (117 BDI-II incomplete). Females accounted for 61.3% of the respondents, and the median age was 22 years (IQR = 4). The prevalence of DS was 29.5%. Specifically, 14.0% had mild depression, 11.1% had moderate depression, and 4.5% had severe depression. The main risk factors for DS were age, being female, bisexual/asexual orientation, living with partner/housemates, poor economic status (worsened by living far from home), less than 90 min of weekly exercise, relatives with psychiatric disorders, personal chronic disease, judging medical school choice negatively, unsatisfying friendships with classmates, competitive and hostile climate among classmates, thinking that medical school hinders specific activities and being worried about not measuring up to the profession. Protective factors included family cohesion, hobbies, intellectual curiosity as a career motivation and no worries about the future.

Conclusion

Italian medical students are at high risk of reporting DS, similar to the global population of medical students’. Medical schools must make efforts to implement preventive and treatment interventions by offering counselling and working on modifiable factors, such as lifestyle and learning climate.

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<![CDATA[The faster, the better? Relationships between run-up speed, the degree of difficulty (D-score), height and length of flight on vault in artistic gymnastics]]> https://www.researchpad.co/article/5c99030dd5eed0c484b98b90

On vault in artistic gymnastics, a high run-up speed is thought to be important when performing difficult vaults. To test this assumption in a large cohort of elite athletes, we calculated the correlations between the run-up speed, scores, height and length of flight for handspring-, Tsukahara- and Yurchenko-style vaults and compared the performances of male and female elite and junior athletes (n = 407) during the 2016 European Championships. In females, run-up speed correlated significantly with the difficulty (D-) score and height of flight for all vaulting styles (r ≤ 0.80). In males, run-up speed correlated significantly with the D-score, height and length of flight of Tsukahara (r ≤ 0.69) and Yurchenko vaults only (r ≤ 0.65). Males reached 8–9% higher run-up speeds performing handspring and Tsukahara vaults than did females, but similar run-up speeds performing Yurchenko vaults. Elite females achieved higher run-up speeds than junior females performing Yurchenko vaults. Elite males displayed higher run-up speeds than junior males performing handspring and Tsukahara vaults. We conclude that, in females, more difficult vaults require higher run-up speeds than vaults with lower D-scores and thus, within the measured range of speeds, the faster the run-up, the better, regardless of vaulting style. Males, on the other hand, may not need to exhaust their sprinting capacity, even for the most difficult vaults. Finally, the knowledge of the required run-up speed for each vault helps coaches to estimate each athlete’s potential and/or to focus the training on developing the required physical qualities.

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<![CDATA[Preadolescent children’s perception of power imbalance in bullying: A thematic analysis]]> https://www.researchpad.co/article/5c8c194ad5eed0c484b4d34b

Bullying in schools is associated with an extensive public health burden. Bullying is intentional and goal oriented aggressive behavior in which the perpetrator exploits an imbalance of power to repeatedly dominate the victim. To differentiate bullying from aggressive behavior, assessment must include a valid measure of power imbalance as perceived by the victim. And yet, to date, there remains no agreement as to how to most accurately measure power imbalance among preadolescent children. This qualitative study explored children’s (age 9 to 11) understanding of power imbalance through thematic analysis of focus group discussions. Subthemes that emerged as influencing power imbalance include: age of victim, peer valued characteristics, and group membership and position. Subthemes of empathy and peer valued characteristics emerged as protecting against the negative impact of power imbalance.

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<![CDATA[Boost your brain, while having a break! The effects of long-term cognitively engaging physical activity breaks on children’s executive functions and academic achievement]]> https://www.researchpad.co/article/5c897718d5eed0c4847d2449

Classroom-based physical activity (PA) is gaining attention in terms of its potential to enhance children’s cognitive functions, but it remains unclear as to which specific modality of PA affects cognitive functions most. The aim of the study was to examine the effects of qualitatively different PA breaks on children’s cognitive outcomes. Children (N = 142) aged between 7 and 9 years were allocated to a 20-week classroom-based PA program, with either high physical exertion and high cognitive engagement (combo group), high physical exertion and low cognitive engagement (aerobic group), or low physical exertion and high cognitive engagement (cognition group). Executive functions (updating, inhibition, shifting) and academic achievement (mathematics, spelling, reading) were measured pre- and post-intervention. Results showed that the combo group profited the most displaying enhanced shifting and mathematic performance. The cognition group profited only in terms of enhanced mathematic performance, whereas the aerobic group remained unaffected. These results suggest that the inclusion of cognitively engaging PA breaks seem to be a promising way to enhance school children’s cognitive functions.

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<![CDATA[Match-play movement and metabolic power demands of elite youth, sub-elite and elite senior Australian footballers]]> https://www.researchpad.co/article/5c818e8dd5eed0c484cc250f

Aims

Currently minimal research has quantified physical requirement differences in match-play between youth and senior Australian football players. The aim of the current research was to describe and compare the movement profiles and energy cost of youth, sub-elite and elite senior Australian football match-play.

Methods

Fifty-seven Australian footballers playing in an elite senior 20, sub-elite senior 16 and elite youth competition 21 participated in this study. Distance, speed based indices and metabolic power measures recording via Global Positioning System (GPS) devices were compared across three competition tiers. Kicks and handballs were collected via a commercial statistics provider (Champion Data) and compared across the competition tiers.

Results

Youth players recorded less field time (elite: ES = 1.37/sub-elite: ES = 1.68), total distance (elite: ES = 1.64 /sub-elite: ES = 1.55) and high speed running (elite: ES = 0.90/sub-elite: ES = 0.26) compared to the elite and sub-elite players. The average energy cost of elite (ES = 2.19) and sub-elite (ES = 1.58) match-play was significantly higher that youth match-play.

Conclusions

A progressive increase regarding physical demands was evident across AF competition tiers. The findings suggest that sub-elite match-play can provide a viable pathway for youth players to develop physical capacity and technical skills before transitioning to elite senior match-play.

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<![CDATA[The effect of contact sport expertise on postural control]]> https://www.researchpad.co/article/5c6f14f5d5eed0c48467abb2

It has been demonstrated that expertise in sport influences standing balance ability. However, little is known concerning how physical contact in sport affects balance ability. The aim of this study was to examine whether differences between contact and limited-contact sport experiences results in differences in postural control. Twenty male collegiate athletes (10 soccer/contact, 10 baseball/limited contact) and ten male untrained students stood quietly on a force plate under various bipedal and unipedal conditions, with and without vision. Significant differences for sway area and COP speed were found between the soccer players and the other two groups for unipedal stances without vision. Soccer players were found to have superior postural control compared with participants involved in limited contact sport or no sport at all. Contact sports may lead to increased postural control through enhanced use of proprioceptive and vestibular information.

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<![CDATA[The Sport Concussion Assessment Tool (SCAT2) for evaluating civilian mild traumatic brain injury. A pilot normative study]]> https://www.researchpad.co/article/5c76fe2cd5eed0c484e5b651

Self-report measures, particularly symptom inventories, are critical tools for identifying patients with persistent post-concussion symptoms and their follow-up. Unlike in military or sports-related assessment, in general civilian settings pre-injury levels of concussion-like symptoms are lacking. Normative data are available in adolescent and college populations, but no reference data exist to guide clinical adult explorations. The purpose of this study was to use the second edition of the Sport Concussion Assessment Tool (SCAT2) to profile a cohort of 60 healthy community volunteers who had not sustained a head injury. Participating volunteers underwent MRI scanning and were evaluated with the Hospital Anxiety and Depression Scale (HADS). Participants reported a median of 3 concussion-like symptoms and the 97.5 percentile score was found at 10.5 symptoms, out of a total of 22. The median severity score was 4.9 points, and 28.9 was the upper limit of the reference interval. Only 10 participants (16.7%) did not endorse any symptom. The most frequently endorsed symptom was feeling difficulty in concentrating, with 41.7% of the sample reporting it. Age, sex and general distress, anxiety and depressive symptoms were not associated with concussion-like symptoms. Our data yielded elevated cut-offs scores for both the number of symptoms and the symptom severity. In conclusion, postconcussive-like symptoms are frequent in the general non-concussed adult population and it should be taken into account in any future models developed for screening patients at risk of developing physical, cognitive, and psychological complaints following mild traumatic injury.

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<![CDATA[Workplace burnout and health issues among Colombian correctional officers]]> https://www.researchpad.co/article/5c6c75e7d5eed0c4843d047c

Introduction

Correctional employees typically work under adverse conditions that may enhance the occurrence of different negative psychological states. Burnout constitutes a high-risk phenomenon that may affect people’s physical/mental health and welfare, especially in vulnerable occupational groups.

Objectives

The aim of this study was to characterize the burnout profile of correctional officers, and to associate their burnout profile with health issues and lifestyle factors.

Methods

The full sample was composed of 219 Colombian correctional officers with a mean age of 30.18 years. A questionnaire composed of three sections was employed: demographic data, burnout, and health information.

Results

A high proportion of participants reported burnout indicators, also significantly correlated to their health indicators and lifestyle factors. Cluster analyses were used in order to characterize the burnout/age (model A) and burnout/age/psychological disturbance (model B) profiles of correctional officers. Furthermore, significant differences were found when comparing frequencies of alcohol consumption and physical exercise (lifestyle indicators) and perceived social support of officers depending on their profile.

Conclusions

the discussion focused on the negative impact of burnout on health, and on the importance of strengthening occupational programs aimed at reducing the impact of hazardous working conditions that contribute to the development of burnout, and to the arise different mid and long-term health complains among correctional workers.

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<![CDATA[Cardiopulmonary responses to maximal aerobic exercise in patients with cystic fibrosis]]> https://www.researchpad.co/article/5c6dca0ed5eed0c48452a718

Cystic fibrosis (CF) is a debilitating chronic condition, which requires complex and expensive disease management. Exercise has now been recognised as a critical factor in improving health and quality of life in patients with CF. Hence, cardiopulmonary exercise testing (CPET) is used to determine aerobic fitness of young patients as part of the clinical management of CF. However, at present there is a lack of conclusive evidence for one limiting system of aerobic fitness for CF patients at individual patient level. Here, we perform detailed data analysis that allows us to identify important systems-level factors that affect aerobic fitness. We use patients’ data and principal component analysis to confirm the dependence of CPET performance on variables associated with ventilation and metabolic rates of oxygen consumption. We find that the time at which participants cross the gas exchange threshold (GET) is well correlated with their overall performance. Furthermore, we propose a predictive modelling framework that captures the relationship between ventilatory dynamics, lung capacity and function and performance in CPET within a group of children and adolescents with CF. Specifically, we show that using Gaussian processes (GP) we can predict GET at the individual patient level with reasonable accuracy given the small sample size of the available group of patients. We conclude by presenting an example and future perspectives for improving and extending the proposed framework. The modelling and analysis have the potential to pave the way to designing personalised exercise programmes that are tailored to specific individual needs relative to patient’s treatment therapies.

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<![CDATA[Association of physical fitness components and health-related quality of life in women with systemic lupus erythematosus with mild disease activity]]> https://www.researchpad.co/article/5c76fe31d5eed0c484e5b6cc

Objectives

To study the association of different components of physical fitness [flexibility, muscle strength and cardiorespiratory fitness (CRF)] and a clustered fitness score with health-related quality of life (HRQoL) in women with systemic lupus erythematosus (SLE) and to analyze whether participants with high fitness level have better HRQoL.

Methods

This cross-sectional study included 70 women with SLE (aged 42.5; SD 13.9 years). The back-scratch test assessed flexibility, the 30-sec chair stand and handgrip strength tests assessed muscle strength, and the 6-min walk test (n = 49) assessed CRF. HRQoL was assessed through the 36-item Short-Form Health Survey (SF-36).

Results

Flexibility was positively associated with the physical function dimension and the physical component summary (PCS) (rpartial between 0.26 and 0.31; p<0.05), and negatively related with social functioning dimension (rpartial = -0.26; p<0.05). Muscle strength was positively associated with the physical function, physical role, bodily pain dimensions and the PCS (rpartial between 0.27 and 0.49; all p<0.05). CRF was positively associated with the physical function and bodily pain dimensions, and PCS (rpartial between 0.39 and 0.65; all p<0.05). The clustered fitness score was associated with the physical function (B = 17.16) and bodily pain (B = 14.35) dimensions, and the PCS (B = 6.02), all p<0.005. Patients with high fitness level had greater scores in the physical function, physical role, and bodily pain dimensions and the PCS, all p≤0.05.

Conclusions

Our study suggests that muscle strength and CRF are positively associated with HRQoL, while flexibility showed contradictory results. These findings highlight the importance of maintaining adequate fitness levels in women with SLE.

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<![CDATA[Overcoming the problem of multicollinearity in sports performance data: A novel application of partial least squares correlation analysis]]> https://www.researchpad.co/article/5c6f1492d5eed0c48467a325

Objectives

Professional sporting organisations invest considerable resources collecting and analysing data in order to better understand the factors that influence performance. Recent advances in non-invasive technologies, such as global positioning systems (GPS), mean that large volumes of data are now readily available to coaches and sport scientists. However analysing such data can be challenging, particularly when sample sizes are small and data sets contain multiple highly correlated variables, as is often the case in a sporting context. Multicollinearity in particular, if not treated appropriately, can be problematic and might lead to erroneous conclusions. In this paper we present a novel ‘leave one variable out’ (LOVO) partial least squares correlation analysis (PLSCA) methodology, designed to overcome the problem of multicollinearity, and show how this can be used to identify the training load (TL) variables that influence most ‘end fitness’ in young rugby league players.

Methods

The accumulated TL of sixteen male professional youth rugby league players (17.7 ± 0.9 years) was quantified via GPS, a micro-electrical-mechanical-system (MEMS), and players’ session-rating-of-perceived-exertion (sRPE) over a 6-week pre-season training period. Immediately prior to and following this training period, participants undertook a 30–15 intermittent fitness test (30-15IFT), which was used to determine a players ‘starting fitness’ and ‘end fitness’. In total twelve TL variables were collected, and these along with ‘starting fitness’ as a covariate were regressed against ‘end fitness’. However, considerable multicollinearity in the data (VIF >1000 for nine variables) meant that the multiple linear regression (MLR) process was unstable and so we developed a novel LOVO PLSCA adaptation to quantify the relative importance of the predictor variables and thus minimise multicollinearity issues. As such, the LOVO PLSCA was used as a tool to inform and refine the MLR process.

Results

The LOVO PLSCA identified the distance accumulated at very-high speed (>7 m·s-1) as being the most important TL variable to influence improvement in player fitness, with this variable causing the largest decrease in singular value inertia (5.93). When included in a refined linear regression model, this variable, along with ‘starting fitness’ as a covariate, explained 73% of the variance in v30-15IFT ‘end fitness’ (p<0.001) and eliminated completely any multicollinearity issues.

Conclusions

The LOVO PLSCA technique appears to be a useful tool for evaluating the relative importance of predictor variables in data sets that exhibit considerable multicollinearity. When used as a filtering tool, LOVO PLSCA produced a MLR model that demonstrated a significant relationship between ‘end fitness’ and the predictor variable ‘accumulated distance at very-high speed’ when ‘starting fitness’ was included as a covariate. As such, LOVO PLSCA may be a useful tool for sport scientists and coaches seeking to analyse data sets obtained using GPS and MEMS technologies.

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<![CDATA[The demanding grey zone: Sport indices by cardiac magnetic resonance imaging differentiate hypertrophic cardiomyopathy from athlete’s heart]]> https://www.researchpad.co/article/5c6f152bd5eed0c48467ae7f

Background

We aimed to characterize gender specific left ventricular hypertrophy using a novel, accurate and less time demanding cardiac magnetic resonance (CMR) quantification method to differentiate physiological hypertrophy and hypertrophic cardiomyopathy based on a large population of highly trained athletes and hypertrophic cardiomyopathy patients.

Methods

Elite athletes (n = 150,>18 training hours/week), HCM patients (n = 194) and athletes with hypertrophic cardiomyopathy (n = 10) were examined by CMR. CMR based sport indices such as maximal end-diastolic wall thickness to left ventricular end-diastolic volume index ratio (EDWT/LVEDVi) and left ventricular mass to left ventricular end-diastolic volume ratio (LVM/LVEDV) were calculated, established using both conventional and threshold-based quantification method.

Results

Whereas 47.5% of male athletes, only 4.1% of female athletes were in the grey zone of hypertrophy (EDWT 13-16mm). EDWT/LVEDVi discriminated between physiological and pathological left ventricular hypertrophy with excellent diagnostic accuracy (AUCCQ:0.998, AUCTQ:0.999). Cut-off value for LVM/LVEDVCQ<0.82 mm×m2/ml and for EDWT/LVEDViTQ<1.27 discriminated between physiological and pathological left ventricular hypertrophy with a sensitivity of 77.8% and 89.2%, a specificity of 86.7% and 91.3%, respectively. LVM/LVEDV evaluated using threshold-based quantification performed significantly better than conventional quantification even in the male subgroup with EDWT between 13-16mm (p<0.001).

Conclusions

Almost 50% of male highly trained athletes can reach EDWT of 13 mm. CMR based sport indices provide an important tool to distinguish hypertrophic cardiomyopathy from athlete’s heart, especially in highly trained athletes in the grey zone of hypertrophy.

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<![CDATA[Hopping in hypogravity—A rationale for a plyometric exercise countermeasure in planetary exploration missions]]> https://www.researchpad.co/article/5c6dca14d5eed0c48452a748

Moon and Mars are considered to be future targets for human space explorations. The gravity level on the Moon and Mars amount to 16% and 38%, respectively, of Earth’s gravity. Mechanical loading during the anticipated habitual activities in these hypogravity environments will most likely not be sufficient to maintain physiological integrity of astronauts unless additional exercise countermeasures are performed. Current microgravity exercise countermeasures appear to attenuate but not prevent ‘space deconditioning’. However, plyometric exercises (hopping and whole body vibration) have shown promise in recent analogue bed rest studies and may be options for space exploration missions where resources will be limited compared to the ISS. This paper therefore tests the hypothesis that plyometric hop exercise in hypogravity can generate sufficient mechanical stimuli to prevent musculoskeletal deconditioning. It has been suggested that hypogravity-induced reductions in peak ground reaction force (peak vertical GRF) can be offset by increases in hopping height. Therefore, this study investigated the effects of simulated hypogravity (0.16G, 0.27G, 0.38G, and 0.7G) upon sub-maximal plyometric hopping on the Verticalised Treadmill Facility, simulating different hypogravity levels. Results show that peak vertical GRF are negatively related to simulated gravity level, but positively to hopping height. Contact times decreased with increasing gravity level but were not influenced through hopping height. In contrast, flight time increased with decreasing gravity levels and increasing hopping height (P < 0.001). The present data suggest that the anticipated hypogravity-related reductions of musculoskeletal forces during normal walking can be compensated by performing hops and therefore support the idea of plyometric hopping as a robust and resourceful exercise countermeasure in hypogravity. As maximal hop height was constrained on the VTF further research is needed to determine whether similar relationships are evident during maximal hops and other forms of jumping.

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<![CDATA[A pilot study of metabolic fitness effects of weight-supported walking in women with obesity]]> https://www.researchpad.co/article/5c76fdecd5eed0c484e5b0c0

Background

This is an exploratory pilot study of novel technology enabling people with mobility disability to walk with minimal effort, in the “sedentary range”. The study’s premise is that impairment of the leading physical activity of daily living, walking, is a major contributor to a dysmetabolic state driving many prevalent “civilization diseases” associated with insulin resistance.

Methods

We explore within-subject changes in standard oral glucose tolerance (OGT) tests including metabotropic molecules after 22 twice-weekly, 30-minute bouts of weight-supported light-moderate physical activity in 16 non-diabetic obese, otherwise healthy, reproductive-age, volunteer women walking on an “anti-gravity” lower-body positive pressure (LBPP) treadmill.

Results

Subjects had reference base-line fasting plasma glucose and triglycerides (TG) but 2-hr OGT insulin levels of 467 ± 276 pmol • liter-1 (mean± S.D.) indicating nascent insulin resistance, compared to post-study 308 ± 179 (p = 0.002). Fasting TG decreased from 0.80 ± 0.30 mmol • liter-1 to 0.71 ± 0.25 (p = 0.03). Concomitantly plasma total ghrelin decreased from 69.6 ± 41.6 pmol • liter-1 to 56.0 ± 41.3 (p = 0.008). There were no statistically significant changes in body weight or any correlations between weight change and cardiometabolic markers. However, there were robust positive correlations between changes among different classes of peptides including C-reactive protein–Interleukin 6, leptin–adiponectin, β-endorphin–oxytocin and orexin A (r 2 = 0.48–0.88).

Conclusion

We conclude that brief, low-dose physical activity, walking on an anti-gravity LBPP treadmill may improve cardiometabolic risk, exhibiting favorable changes in neuro-regulatory peptides without weight loss in people with problems walking.

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<![CDATA[Does aerobic exercise associated with tryptophan supplementation attenuates hyperalgesia and inflammation in female rats with experimental fibromyalgia?]]> https://www.researchpad.co/article/5c76fddfd5eed0c484e5afa2

The objective of this study was to verify the effects of aerobic exercise associated with tryptophan (TRP) supplementation on hyperalgesia, as well as on cortisol, IL-6 and TNF concentrations in female rats with experimental fibromyalgia (FM). Female Wistar rats (initial body weight: ~ 350 g; age: 12 months) were randomly divided into 5 groups: CON (Control); F (Fibromyalgia induced); FE (Fibromyalgia induced plus exercise); FES (Fibromyalgia induced plus exercise and TRP supplementation) and FS (Fibromyalgia induced plus TRP supplementation). Fibromyalgia was induced with two injections (20 μL) of acidic saline (pH 4.0) into the right gastrocnemius muscle with a 3-day interval. Control animals received the same doses of neutral saline (pH 7.4). The exercised animals underwent progressive low-intensity aerobic exercise (LIAE) on a treadmill (10–12 m/min, 30–45 min/day, 5 days/week) for three weeks. During this period, the supplemented animals received a TRP supplemented diet (210 g/week), while the others received a control diet. Mechanical hyperalgesia was evaluated weekly and serum cortisol and muscle IL-6 and TNF concentrations were assessed after three weeks of interventions. Experimental FM caused bilateral hind paw hyperalgesia and augmented serum cortisol and muscle IL-6 concentrations. After 3 weeks of interventions, LIAE alone reduced hyperalgesia (151%) and reduced serum cortisol concentrations (72%). Tryptophan supplementation itself diminished hyperalgesia (57%) and reduced serum cortisol concentrations (67%). Adding TRP supplementation to LIAE did not further reduce hyperalgesia significantly (11%), which was followed by an important decrease in muscle IL-6 concentrations (68%), though reduction in serum cortisol pulled back to 45%. Muscle TNF concentrations were not affected. In conclusion, the association of TRP supplementation to LIAE does not potentiate significantly the reduction of bilateral mechanical hyperalgesia promoted by LIAE in female rats with experimental FM, however an important decrease in IL-6 is evident.

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