1,369 research outputs found
Prediction of Rowing Functional Threshold Power using Body Mass, Blood Lactate and GxT Peak Power Data.
International Journal of Exercise Science 16(4): 31-41, 2023. Functional Threshold Power (FTP) is a validated index of a maximal quasi steady-state cycling intensity. The central component of the FTP test is a maximal 20-min time-trial effort. A model to predict FTP from a cycling graded exercise test (m-FTP) was published that estimated FTP without the requirement of the exhaustive 20-min time-trial. The predictive model (m-FTP) was trained (developed to find the best combination of weights and bias) on a homogenous group of highly-trained cyclists and triathletes. This investigation appraised the external validity of the m-FTP model vis-Ć -vis the alternate modality of rowing. The reported m-FTP equation purports to be sensitive to both changing levels of fitness, and exercise capacity. To assess this claim, eighteen (7 female, 11 male) heterogeneously-conditioned rowers were recruited from regional rowing clubs. The first rowing test was a 3-min graded incremental test with a 1-min break between increments. The second test was a rowing adapted FTP test. There were no significant differences between rowing FTP (r-FTP) and m-FTP (230 Ā± 64 versus 233 Ā± 60 W, respectively, F = 1.13, P = 0.80). Computed Bland-Altman 95% LoA between r-FTP and m-FTP were (-18 W to + 15 W), sy.x was 7 W, and 95 %CI of regression were 0.97 to 0.99. The r-FTP equation was demonstrated to be effective in predicting a rowers 20-min maximum power; further appraisal of the physiological response to rowing for 60-min at the corresponding calculated FTP requires investigation
Is the FTP Test a Reliable, Reproducible and Functional Assessment Tool in Highly-Trained Athletes?
International Journal of Exercise Science 12(4): 1334-1345, 2019. The aim of the current study was to assess reliability of the Functional Threshold Power test (FTP) and the corresponding intensity sustainable for 1-hour in a āquasi-steady stateā. Highly-trained athletes (n = 19) completed four non-randomized tests over successive weeks on a Wattbike; a 3-min incremental test (GxT) to exhaustion, two 20-min FTP tests and a 60-min test at computed FTP (cFTP). Power at cFTP was calculated by reducing 20-min FTP data by 5% and was compared with power at Dmax and lactate threshold (TLac). Ventilatory and blood lactate (BLa) responses to cFTP were measured to determine whether cFTP was quasi-steady state. Agreement between consecutive FTP tests was quantified using a Bland-Altman plot with 95% limits of agreement (95% LoA) set at Ā± 20 W. Satisfactory agreement between FTP tests was detected (95% LoA = +13 and -17 W, bias +2 W). The 60-min effort at cFTP was successfully completed by 17 participants, and BLa and ventilatory data at cFTP were classified as quasi-steady state. A 5% increase in power above cFTP destabilized BLa data (p \u3c 0.05) and prompted VO2 to increase to peak GxT rates. The FTP test is therefore deemed representative of the uppermost power a highly-trained athlete can maintain in a quasi-steady state for 60-min. Agreement between repeated 20-min FTP tests was judged acceptable
Do Critical and Functional Threshold Powers Equate in Highly- Trained Athletes?
International Journal of Exercise Science 14(4): 45-59, 2021. The purpose of this investigation was to determine whether Critical Power (CP) and Functional Threshold Power (FTP) can be used interchangeably for a highly-trained group of cyclists and triathletes. CP was ascertained using multiple fixed load trials and FTP determined from a single cycling trial. Three different models for the determination of CP were initially addressed, one hyperbolic (Hmodel) and two linear (Jmodel and Imodel). The Jmodel was identified as most appropriate for a comparison with FTP. The Jmodel and FTP were not found to be interchangeable as ANOVA detected significant differences (282 Ā± 53 vs. 266 Ā± 55 W, p \u3c 0.001) between these indices and the associated Bland-Altman 95% limits of agreement exceeded those set a priori. As the Jmodel was found to be consistently higher than FTP, a correction factor was posited to anticipate CP from FTP in this homogenous group of athletes using the mean bias (16 W). An alternate method for assessing CP trial intensities using Dmax as a proxy for ventilatory threshold is also proposed. The concept of both CP and FTP representing a maximal metabolic steady-state requires further investigation as the mechanical power at CP was significantly greater than at FTP
Evaluation of the Effectiveness of Disseminating Workplace Health Promotion Resources to Businesses
Encouraging workplaces to undertake health promotion is important yet little is known of the types of information small and medium size workplaces would find useful. Two resources on workplace health promotion were mailed to 213 workplaces. The resources provided information on the benefits of workplace health promotion, suggestions for low-cost activities and components of a sustainable program. 62% of respondents rated the resources as either āvery usefulā or āsomewhat usefulā. Workplaces in ācontemplationā and āpreparationā stages of change for engaging in WHP were most likely to have undertaken an activity to support the health and well-being of employees or be intending to, as a result of reading the resources .The findings of this study provide useful information on the reach and impact of dissemination of health promotion resources by mail to workplaces, and particularly small businesses
The Secretome of Mesenchymal Stem Cells Prevents Islet Beta Cell Apoptosis via an IL-10-Dependent Mechanism:The Secretome of Mesenchymal Stem Cells
A dynamic network approach for the study of human phenotypes
The use of networks to integrate different genetic, proteomic, and metabolic
datasets has been proposed as a viable path toward elucidating the origins of
specific diseases. Here we introduce a new phenotypic database summarizing
correlations obtained from the disease history of more than 30 million patients
in a Phenotypic Disease Network (PDN). We present evidence that the structure
of the PDN is relevant to the understanding of illness progression by showing
that (1) patients develop diseases close in the network to those they already
have; (2) the progression of disease along the links of the network is
different for patients of different genders and ethnicities; (3) patients
diagnosed with diseases which are more highly connected in the PDN tend to die
sooner than those affected by less connected diseases; and (4) diseases that
tend to be preceded by others in the PDN tend to be more connected than
diseases that precede other illnesses, and are associated with higher degrees
of mortality. Our findings show that disease progression can be represented and
studied using network methods, offering the potential to enhance our
understanding of the origin and evolution of human diseases. The dataset
introduced here, released concurrently with this publication, represents the
largest relational phenotypic resource publicly available to the research
community.Comment: 28 pages (double space), 6 figure
Use of a liquid nicotine delivery product to promote smoking cessation
<p>Abstract</p> <p>Background</p> <p>Despite access to various pharmacotherapies and counseling support to aid cessation, smokers typically demonstrate quit rates below 50%. This report describes the results of a Phase 2a study exploring the efficacy of a liquid nicotine delivery system as an aid to smoking cessation assessed after 12 weeks of therapy.</p> <p>Methods</p> <p>A single-arm Phase 2a study was conducted. Community-based smokers (ages 18+ years, smoking at least 10 cigarettes daily for the past year and interested in making a quit attempt) were recruited and completed clinic visits at 2 week intervals over the 12 week study period where carbon monoxide levels were assessed and the Smoke-Break product was rated on taste and overall satisfaction. Participants were provided with a supply of liquid nicotine cigarettes (e.g., Smoke-Break) at each clinic visit. A total of 69 smokers were enrolled and received the intervention product (intention to treat group, ITT) and 52 smokers verified participation (according to protocol group, ATP).</p> <p>Results</p> <p>The cessation rate at 12 weeks after the baseline visit, assessed as the bioverified point prevalence of abstinence, was 71.1% (95% confidence interval [CI] 58.8%-83.5%) in the ATP group and 53.6% (41.8%-65.4%) in the ITT group. Participants rated the liquid nicotine delivery system highly and also expressed general satisfaction. Few adverse events were identified with no serious adverse events.</p> <p>Conclusions</p> <p>These results support the efficacy of the liquid nicotine delivery system in smoking cessation. If this nicotine delivery product proves to be effective in larger trials, it could represent an inexpensive, readily accessible and well-tolerated agent to promote smoking cessation.</p> <p>Trial Registration</p> <p>This trial is registered at clinicaltrials.gov as study NCT00715871.</p
Capsule Size Alters the Timing of Metabolic Alkalosis Following Sodium Bicarbonate Supplementation
Active Tension Network model suggests an exotic mechanical state realized in epithelial tissues.
Mechanical interactions play a crucial role in epithelial morphogenesis, yet understanding the complex mechanisms through which stress and deformation affect cell behavior remains an open problem. Here we formulate and analyze the Active Tension Network (ATN) model, which assumes that the mechanical balance of cells within a tissue is dominated by cortical tension and introduces tension-dependent active remodeling of the cortex. We find that ATNs exhibit unusual mechanical properties. Specifically, an ATN behaves as a fluid at short times, but at long times supports external tension like a solid. Furthermore, an ATN has an extensively degenerate equilibrium mechanical state associated with a discrete conformal - "isogonal" - deformation of cells. The ATN model predicts a constraint on equilibrium cell geometries, which we demonstrate to approximately hold in certain epithelial tissues. We further show that isogonal modes are observed in the fruit y embryo, accounting for the striking variability of apical areas of ventral cells and helping understand the early phase of gastrulation. Living matter realizes new and exotic mechanical states, the study of which helps to understand biological phenomena
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