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111.
Saliva provides a convenient and noninvasive matrix for assessing specific physiological parameters, including some biomarkers of exercise. We investigated whether the total protein concentration of whole saliva (TPWS) would reflect the anaerobic threshold during an incremental exercise test. After a warm-up period, 13 nonsmoking men performed a maximum incremental exercise on a cycle ergometer. Blood and stimulated saliva were collected during the test. The TPWS anaerobic threshold (PAT) was determined using the Dmax method. The PAT was correlated with the blood lactate anaerobic threshold (AT; r = .93, p < .05). No significant difference (p = .16) was observed between PAT and AT. Thus, TPWS provides a convenient and noninvasive matrix for determining the anaerobic threshold during incremental exercise tests.  相似文献   
112.
Abstract

The main purpose of this study was to track the performance and health-related physical fitness of girls from Brazil's Cariri region. In the “Healthy Growth in Cariri Study”, 294 girls from public and private schools were divided into four age cohorts – 8, 10, 12, and 14 years – and followed for three consecutive years, with an assessment every 6 months. Shuttle run, hand grip, standing long jump, trunk lift, curl-up, 12-min run, and fatness were used to rate physical fitness performance and health-related components on each of six occasions. Tracking was done in a stepwise manner, using auto-correlation, by modelling the individual history of change in performance of each girl, and using Foulkes and Davies’ γ-coefficient. SPSS 18.0 and TIMEPATH were used for data analysis. Auto-correlations evidenced low-to-moderate values in almost all components of performance and health-related physical fitness. Intra-individual tracking analysis showed large variation in all fitness components as a result of a wide spread in individual history of change in fitness performance. Population estimates of γ were low in all tests. Our results show low-to-moderate tracking of physical fitness components of girls. A wide range of intra-individual and inter-variability in fitness development was observed.  相似文献   
113.

In the current study, we examined the relationship between serum creatine kinase (CK) activity following upper body resistance exercise with a 1- or 3-min rest between sets. Twenty men performed two sessions, each consisting of four sets with a 10-repetition maximum load. The results demonstrated significantly greater volume for the 3-min condition (M = 4,156 kg, SD = 867, for 3 min; vs. M = 3,503 kg, SD = 759, for 1 min; p < .001), with no significant differences in delta CK activity between conditions (p = .574). Nevertheless, there was a weak correlation between the delta CK activity and total volume of exercise completed (r = .55 with a 1-min rest, and r =.45 with a 3-min rest). Therefore, the volume following upper body resistance exercise correlates weakly with serum CK levels, irrespective of rest interval length between sets.  相似文献   
114.
Abstract

This study aimed to produce age- and sex-specific physical fitness reference data for Portuguese youth; to report the prevalence of youth in the healthy zone of physical fitness according to the FITNESSGRAM® criteria; to verify the agreement between the Portuguese physical fitness percentiles and the FITNESSGRAM® healthy zones. In 2008, 22,048 Portuguese children and adolescents (10–18 years) were evaluated. Physical fitness (curl-ups, push-ups, 20-m shuttle run and modified-back-saver-sit-and-reach tests) was evaluated using the FITNESSGRAM® Test Battery 8.0. Smoothed percentile curves were estimated using Cole’s LMS method. Boys consistently outperformed girls in every physical fitness test, except for the modified-back-saver-sit-and-reach tests. In both sexes and for all physical fitness tests, higher percentile values were observed at older ages. The 50th percentile of all physical fitness tests had the highest accuracy to discriminate between under healthy zone and healthy zone of the FITNESSGRAM®. Portuguese schools and physical education teachers may considerer the 50th percentile for age and sex or the FITNESSGRAM® criteria for classifying participants in the healthy zone as acceptable cut-offs, above which youth should be considered fit. These reference values can be used as normative data and for baseline values for subsequent surveillance of the physical fitness of Portuguese youth.  相似文献   
115.
The paper reports a longitudinal study of factors associated with reading ability in a large sample (N=748) of children. Reading was assessed when the children were aged seven and later at age nine. The associated measures included measures of background, experiences and earlier cognitive development. It was found that the correlation between reading at age seven and reading at age nine was 0.87. However, reading at seven and nine were both associated with the background measures and to a lesser extent with experiential measures. Reading at seven was associated with earlier cognitive development. The implications of the results are discussed.  相似文献   
116.
117.
This paper analyses how knowledge-based practices adopted by innovation intermediaries enable them to generate value for themselves when collaborating with their clients. While the literature focuses on value creation for their client organisations, little is known about how innovation intermediaries create internal value even though this is essential for ensuring their long-term survival and sustaining their key facilitating role in the innovation system. This understudied issue is explored using empirical evidence from a sub-set of innovation intermediaries, Research and Technology Organisations (RTOs). The results indicate that by capitalising on existing knowledge vested in employees and collaborators as well as understanding and shaping the knowledge base of the innovation ecosystem, innovation intermediaries generate internal value from their involvement in collaborative innovation, which range from different financial to non-financial types of value. Implications for intermediaries, their collaborators and for policymakers are then discussed.  相似文献   
118.
In this paper, we propose a numerically robust blind equalization scheme to mitigate cochannel and intersymbol interferences and separate signals from a convolutive mixture in multiple-input multiple-output (MIMO) communication systems. The robustness of the proposed scheme is achieved through a particular dual-mode operation applied to a constant-modulus-based space-time algorithm that corrects phase rotations. In the first mode of operation, the consistency in the nonlinear estimates of the transmitted signals is ensured. In the second mode, the Euclidean norms of the equalizer coefficient vectors decrease along the iterations, which allows the algorithm to return to the first mode of operation, where the estimation of the transmitted signals really occurs. In particular, we apply this scheme to a multimodulus version of the multiuser Shalvi-Weinstein algorithm (MU-SWA). By means of a deterministic stability analysis assuming the persistence of excitation condition, we show that the dual-mode MU-SWA does not diverge.  相似文献   
119.
The aim was to compare the passive drag-gliding underwater by a numerical simulation and an analytical procedure. An Olympic swimmer was scanned by computer tomography and modelled gliding at a 0.75-m depth in the streamlined position. Steady-state computer fluid dynamics (CFD) analyses were performed on Fluent. A set of analytical procedures was selected concurrently. Friction drag (Df), pressure drag (Dpr), total passive drag force (Df+pr) and drag coefficient (CD) were computed between 1.3 and 2.5 m · s?1 by both techniques. Df+pr ranged from 45.44 to 144.06 N with CFD, from 46.03 to 167.06 N with the analytical procedure (differences: from 1.28% to 13.77%). CD ranged between 0.698 and 0.622 by CFD, 0.657 and 0.644 by analytical procedures (differences: 0.40–6.30%). Linear regression models showed a very high association for Df+pr plotted in absolute values (R2 = 0.98) and after log–log transformation (R2 = 0.99). The CD also obtained a very high adjustment for both absolute (R2 = 0.97) and log–log plots (R2 = 0.97). The bias for the Df+pr was 8.37 N and 0.076 N after logarithmic transformation. Df represented between 15.97% and 18.82% of the Df+pr by the CFD, 14.66% and 16.21% by the analytical procedures. Therefore, despite the bias, analytical procedures offer a feasible way of gathering insight on one’s hydrodynamics characteristics.  相似文献   
120.
The present study aimed to determine the effects of physical training performed by parents on mice offspring adiposity. Male and female parents underwent an aerobic training protocol for 7 weeks. The trained and sedentary parents were allowed to mate and the resultant offspring divided in: S (Offspring from Sedentary Parents), T (Offspring from Trained Parents), ST (Offspring from Sedentary Father and Trained Mother) and TS (Offspring from Trained Father and Sedentary Mother). After weaning, offspring was euthanized, blood collected and samples of mesenteric and inguinal fat pads used to isolate adipocytes for morphologic and histological analyses. Lee index, mesenteric fat pad, sum of visceral fat and total fat weight of female T was reduced in comparison to the other groups (p < 0.05). Periepididymal and sum of visceral fat in male T group was also reduced when compared to the other groups (p < 0.05). The diameter of mesenteric and inguinal adipocytes of T group was smaller compared to all groups comparisons for both sexes (p < 0.05). In summary, exercise training performed by parents reduced visceral offspring adiposity, the diameter of subcutaneous adipocytes and improved metabolic parameters associated to metabolic syndrome.  相似文献   
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