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The purpose of this study was to compare the incremental running tests performed by young soccer players on a treadmill (Tr) and in the field (FTcod: 100 m change of direction and FTcir: 100 m circle). Nineteen players (average age 17.4 ± 1.1 years; body height 172.0 ± 5.7 cm; body mass 68.9 ± 6.7 kg) volunteered to perform incremental Tr , FTcod and FTcir running tests. In all three tests, players ran for 3 min at 8, 10, 12 and 14 km∙h-1 and were given a 1 min rest interval between subsequent stages. Blood lactate concentrations (La-) were measured at 1 min rest intervals and the heart rate (HR) responses of players were recorded during the tests. After a 5 min recovery period, the second part of the test started; players ran at 15 km∙h-1 with velocity increments of 1 km∙h-1 every 1 min until exhaustion. This part was performed to determine maximum HR, maximum La- and the players’ final velocities. The results showed that players had significantly lower La- (F = 6.93, p = 0.07, η2 = 0.46, 95%CI(TR-FTcir) = -1.91/-0.34, 95%CI(TR-FTcod) = -1.59/-0.05) and HR (F = 9.08, p = 0.02, η2 = 0.53, 95%CI(TR-FTcir) = -6.98/-1.68, 95%CI(TR-FTcod) = -7.19/1.08) responses in the Tr test than in the FTcir and FTcod tests at 14 km∙h-1. It was also found that players completed the Tr test (F = 58.22, p = 0.00, η2 = 0.87) at higher final running velocities than the FTcir (95%CI(TR-FTcir) = 1.67/2.78) and FTcod (95%CI(TR-FTcod) = 1.69/2.85) tests. In conclusion, when coaches or sports scientists plan to train at higher running velocities or according to the final velocity in the test, it is advisable to carry out testing in the circumstances under which training will be carried out (in the field or on a treadmill).

The purpose of this study was to compare the incremental running tests performed by young soccer players on a treadmill (Tr) and in the field (FTcod: 100 m change of direction and FTcir: 100 m circle). Nineteen players (average age 17.4 +/- 1.1 years; body height 172.0 +/- 5.7 cm; body mass 68.9 +/- 6.7 kg) volunteered to perform incremental Tr , FTcod and FTcir running tests. In all three tests, players ran for 3 min at 8, 10, 12 and 14 km.h(-1) and were given a 1 min rest interval between subsequent stages. Blood lactate concentrations (La-) were measured at 1 min rest intervals and the heart rate (HR) responses of players were recorded during the tests. After a 5 min recovery period, the second part of the test started; players ran at 15 km.h(-1) with velocity increments of 1 km.h(-1) every 1 min until exhaustion. This part was performed to determine maximum HR, maximum La- and the players' final velocities. The results showed that players had significantly lower La- (F = 6.93, p = 0.07, eta(2) = 0.46, 95%CI(TR-FTcir) -1.91/-0.34, 95%CI(TR-FTcod)= -1.59/-0.05) and HR (F = 9.08, p = 0.02, eta(2) = 0.53, 95%CI(TR-FTcir) = -6.98/-1.68, 95%CI(TR-FTcod)= -7.19/1.08) responses in the Tr test than in the FTcir and FTcod tests at 14 km.h(-1). It was also found that players completed the Tr test (F = 58.22, p = 0.00, eta(2) = 0.87) at higher final running velocities than the FTcir (95%CI(TR-FTcir) = 1.67/2.78) and FTcod (95%CI(TR-FTcod)= 1.69/2.85) tests. In conclusion, when coaches or sports scientists plan to train at higher running velocities or according to the final velocity in the test, it is advisable to carry out testing in the circumstances under which training will be carried out (in the field or on a treadmill). C1 [Koklu, Yusuf; Alemdaroglu, Utku; Demirhan, Ramazan; Arslan, Yunus] Pamukkale Univ, Fac Sport Sci, KINIKLI Kampusu, Denizli, Turkey.

Tendons are dense connective tissues that attach muscles to bone with an indispensable role in locomotion because of their intrinsic properties of storing and releasing muscle- generated elastic energy. Tenomodulin (Tnmd) is a well-accepted gene marker for the mature tendon/ligament lineage and its loss-of -function in mice leads to a phenotype with distinct signs of premature aging on tissue and stem/progenitor cell levels. Based on these findings, we hypothesized that Tnmd might be an important factor in the functional performance of tendons. Firstly, we revealed that Tnmd is a mechanosensitive gene and that the C-terminus of the protein co-localize with collagen I-type fibers in the extracellular matrix. Secondly, using an endurance training protocol, we compared Tnmd knockout mice with wild types and showed that Tnmd deficiency leads to significantly inferior running performance that further worsens with training. In these mice, endurance running was hindered due to abnormal response of collagen I cross-linking and proteoglycan genes leading to an inadequate collagen I fiber thickness and elasticity. In sum, our study demonstrates that Tnmd is required for proper tendon tissue adaptation to endurance running and aids in better understanding of the structural-functional relationships of tendon tissues., Highlights • Tnmd is a mechanosensitive gene and its protein is co-localized with collagen I fibers in the ECM of tendons. • Tnmd knockout mice fail in endurance running tests, a phenotype that worsens with training. • Tnmd knockout tendons had significantly thicker and stiffer collagen I fibers and altered crosslinking gene expression. We performed a multidisciplinary approach to decipher the role of tenomodulin, a gene marker for the mature tendon lineage, in tendon functional performance. Loss-of-function in mice led to significantly inferior endurance running and detailed analyses revealed that tenomodulin is involved in the regulation of collagen I fiber structural and biomechanical properties in response to exercise. Our study expands the current view on the complex structural-functional relationships of tendon tissues, and tenomodulin expression levels may indicate whether an individual is suitable for a certain sport.

The purpose of this research was to develop new tests for an estimate of the record at a 400-meter race. Taking training environment in snow and cold prone areas into consideration, the condition that the test should be carried out on an indoor course （250 meters or less) was imposed. The running test which took running distance within the given time was carried out two times (including a 30-second intermission) in order to measure its total running distance, which gives an estimate of the record at actual race. In the trial test whose total running time was set at 50 seconds, three kinds of conditions that a runner should run within different time at each trial test were established. As a result, a correlation was found only between the total running distance within "25s＋25s" and the record at a 400-meter race, and the regression line formula "Record at a 400-meter race= -0.052x+71.840（seconds）" was established. Therefore, the load setting "25s＋25s" was adopted for running tests., 本研究では，積雪寒冷地の練習環境に対応した400m走のパフォーマンステストを開発する。鍛錬期にあたる12月～ 2月の積雪寒冷地の天候について，筆者の所在地である富山県の天候を例にとると，雪日が平均44.9日（月平均14.9日，気象庁：1981年～2010年の平均）である。日常的な積雪により屋外競技場でのトレーニングができない天候状況の中，富山県内で走行可能な屋内走路施設は最長で250mの走行距離を確保できる。そのため「連続走行距離250m以内」を条件としたテストの開発が求められる。今回，400m走を専門とする選手には様々な生理的特徴を持った者が混在することを考慮し，走行する設定時間に違いを持たせた 3つの条件を実験試技として設けた。各試技における測定値と400m走記録との関係を検証し，400m走記録と最も結びつきの強い実験試技をパフォーマンステストとして提案する。

Summary Study aim: contemporary military activities call for extremely high coordinative motor skills, especially precision, attention focusing and motor adjustment. No obligatory tests assessing those skills are presently used by Polish armed forces. The aim of this study was thus to set up a procedure of assessing running skills involving coordination and motor adjustment, possible to be of military use. Material and methods: a group of 68 male students aged 22–25 years (23.42 ± 2.1 years) volunteered to participate in the study. The following tests were applied: 15-m sprint, shuttle run 3 × 5 m, 15-m slalom run and 15-m squat (on all fours). The tests were applied twice. The sums of all 4 velocities served as the dependent variable; its total variance was partitioned into percent contributions of the standardised results of 4 running tests. Results: it turned out that the total variance was explained in 95% by the 15-m sprint and 15-m squat nearly by half the contributions of the other two variables being non-significant. Two indices were constructed: Speed-strength index (W1) and Speed-agility index (W2). Discussion: the proposed indices representing the speed-strength and speed-agility potentials seem to adequately reflect running-related features required of soldiers performing field tasks. Those indices may also find use in monitoring motor skills of team game players, including their selection.

In this study, the production of ultrapure Na-bentonite by centrifuge based techniques for organo and nano composite bentonite industry was investigated. Various parameters including centrifuging time, solids content, and g force were studied to determine the set points (cut size) for theoretical CEC (cation exchange capacity) and recovery limits. The experimental results were modeled using Response Surface Method (RSM) with high responses (regression & 85% and correlation coefficients & 0.85). it is shown that the commercial centrifugation equipment operating with residence time of 10-15 seconds and g values lower than 300 g such as Multi Gravity separator (MGS), Hydrocyclones and Falcon/Knelson concentrators are not suitable for obtaining pure quality Na-bentonite, since the set point size (5-8 µm) is higher than 2 µm which is defined for bentonite of high smectite contents. The RSM models demonstrate that only the kind of separators such as decanter centrifuges with operational g forces higher than 600 may exhibit the closest set point to 2 µm and thus enable the achievement of an ultra pure quality bentonite product. These assumptions obtained from the developed model were confirmed by running tests on Falcon and Mozley hydrocyclone separators. © 2012 Copyright Taylor and Francis Group, LLC., 00492.STZ.2009-2, The authors would like to thank the Turkish Ministry of Science, Industry and Technology Programme for their financial support to carry out this study which is a part of our project (Project number: 00492.STZ.2009-2).

The results of the experimental investigation of dynamic perfomance of the electric train EPL9T was described. The range of exploitation velociries is appoint., В статье приведены результаты динамических ходовых испытаний электропоезда ЭПЛ9Т в прямых и криволинейных участках пути. Определены коэффициенты горизонтальной и вертикальной динамики, запаса устойчивости от схода колеса с рельса, а также горизонтальные и вертикальные ускорения в салонах вагонов. По уровню динамических показателей установленны условия обращения электропоезда ЭПЛ9Т на железных дорогах., У статті наведені результати динамічних ходових випробувань електропоїзда ЭПЛ9Т в прямих і криволінійних ділянках колії. Визначено коефіцієнти горизонтальної і вертикальної динаміки, запасу стійкості від сходу колеса з рейки, а також горизонтальні і вертикальне прискорення в салонах вагонів. За рівнем динамічних показників встановлено умови обертання електропоїзда ЭПЛ9Т на залізницях.

The results of the experimental investigation of dynamic performance of the electric train EPL9T was described. The range of exploitation velociries is appoint.