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141.
With this research, we sought to establish the accuracy of stride velocity data collected by the s3 Stride Sensor Participants walked along a GAITRite mat at self-selected slow, preferred, and fast velocities, with two s3 Stride Sensors attached to their right foot. The start position was systematically varied such that the GAITRite system would record the second through sixth strides at each walking velocity. Both slow and preferred walking velocities were underestimated by 14% relative to the GAITRite (p < .05), while independent of walking velocity, Strides 2 and 3 were underestimated by 26% and 9% (p < .05), respectively. Researchers should use caution when interpreting data collected at slow and preferred walking velocities and during the first three strides.  相似文献   
142.
The aim of this study was to examine the effectiveness of either a standard care programme (n = 9) or a 12-week supported exercise programme (n = 10) on glycaemic control, β-cell responsiveness, insulin resistance, and lipid profiles in newly diagnosed Type 2 diabetes patients. The standard care programme consisted of advice to exercise at moderate to high intensity for 30 min five times a week; the supported exercise programme consisted of three 60-min supported plus two unsupported exercise sessions per week. Between-group analyses demonstrated a difference for changes in low-density lipoprotein cholesterol only (standard care programme 0.01 mmol · L(-1), supported exercise programme -0.6 mmol · L(-1); P = 0.04). Following the standard care programme, within-group analyses demonstrated a significant reduction in waist circumference, whereas following the supported exercise programme there were reductions in glycosylated haemoglobin (6.4 vs. 6.0%; P = 0.007), waist circumference (101.4 vs. 97.2 cm; P = 0.021), body mass (91.7 vs. 87.9 kg; P = 0.007), body mass index (30.0 vs. 28.7 kg · m(-2); P = 0.006), total cholesterol (5.3 vs. 4.6 mmol · L(-1); P = 0.046), low-density lipoprotein cholesterol (3.2 vs. 2.6 mmol · L(-1); P = 0.028), fasting β-cell responsiveness (11.5 × 10(-9) vs. 7.0 × 10(-9) pmol · kg(-1) · min(-1); P = 0.009), and insulin resistance (3.0 vs. 2.1; P = 0.049). The supported exercise programme improved glycaemic control through enhanced β-cell function associated with decreased insulin resistance and improved lipid profile. This research highlights the need for research into unsupported and supported exercise programmes to establish more comprehensive lifestyle advice for Type 2 diabetes patients.  相似文献   
143.
In this study, we wished to determine whether the observed reduction in quadriceps muscle oxygen availability, reported during repetitive bouts of isometric exercise in simulated sailing efforts (i.e. hiking), is because of restricted muscle blood flow. Six national-squad Laser sailors initially performed three successive 3-min hiking bouts followed by three successive 3-min cycling tests sustained at constant intensities reproducing the cardiac output recorded during each of the three hiking bouts. The blood flow index (BFI) was determined from assessment of the vastus lateralis using near-infrared spectroscopy in association with the light-absorbing tracer indocyanine green dye, while cardiac output was determined from impedance cardiography. At equivalent cardiac outputs (ranging from 10.3±0.5 to 14.8±0.86 L · min(-1)), the increase from baseline in vastus lateralis BFI across the three hiking bouts (from 1.1±0.2 to 3.1±0.6 nM · s(-1)) was lower (P = 0.036) than that seen during the three cycling bouts (from 1.1±0.2 to 7.2±1.4 nM · s(-1)) (Cohen's d: 3.80 nM · s(-1)), whereas the increase from baseline in deoxygenated haemoglobin (by ~17.0±2.9 μM) (an index of tissue oxygen extraction) was greater (P = 0.006) during hiking than cycling (by ~5.3±2.7 μM) (Cohen's d: 4.17 μM). The results suggest that reduced vastus lateralis muscle oxygen availability during hiking arises from restricted muscle blood flow in the isometrically acting quadriceps muscles.  相似文献   
144.
The aim of this study was to assess the effects of a single session of cold or thermoneutral water immersion after a one-off match on muscular dysfunction and damage in soccer players. Twenty-male soccer players completed one match and were randomly divided into cryotherapy (10 min cold water immersion, 10°C, n = 10) and thermoneutral (10 min thermoneutral water immersion, 35°C, n = 10) groups. Muscle damage (creatine kinase, myoglobin), inflammation (C-reactive protein), neuromuscular function (jump and sprint abilities and maximal isometric quadriceps strength), and delayed-onset muscle soreness were evaluated before, within 30 min of the end, and 24 and 48 h after the match. After the match, the players in both groups showed increased plasma creatine kinase activity (30 min, 24 h, 48 h), myoglobin (30 min) and C-reactive protein (30 min, 24 h) concentrations. Peak jump ability and maximal strength were decreased and delayed-onset muscle soreness increased in both groups. However, differential alterations were observed between thermoneutral water and cold water immersion groups in creatine kinase (30 min, 24 h, 48 h), myoglobin (30 min), C-reactive protein (30 min, 24 h, 48 h), quadriceps strength (24 h), and quadriceps (24 h), calf (24 h) and adductor (30 min) delayed-onset muscle soreness. The results suggest that cold water immersion immediately after a one-off soccer match reduces muscle damage and discomfort, possibly contributing to a faster recovery of neuromuscular function.  相似文献   
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146.
本研究的目的是基于乒乓球教练员对人体形态测量、身体素质能力、生理心理素质、心理以及体型因素的基础上,决定选材的原则和标准。这个研究的反馈者包括40名国际水平的乒乓球教练员(26位来自伊朗,14位来自其它国家),他们是随机抽取的,55%的反馈者持有国际教练员资格学位,教练生涯的平均年数是15.74年。大约有50%的认为7~8岁是选材的最合适年龄段;27.5%认为是5~6岁;17.5%认为是9~10岁。根据分析,发现66.5%选择观察方法;48.1%选择科学方法作为选材时优先考虑的方法。总的来说,34.2%认为教育部门对于选材具有最主要的责任。进一步而言,涉及…  相似文献   
147.
148.
Onchidiumtumidiumisaslug-likepulmonatecommonlyfoundinthebrackishmangroveswampsinSingapore.Itleadsanamphibiouslifeonthemudflatsintheintertidalzonewhereitisexposedonlyduringebbtideswhichlastsnomorethan12h.Druingthisperiod,itemergesfromitsburrow,andgrazesonthesurfacealgae.Asthetiderises,itburrowsanddisappearsintothemud.Hence,itisnaturallyexposedto6~12hofenvironmentalhypoxiaeveryday.Thisperiodofhypoxiacanalsobeextendedto24~48hduringcoolorrainydays,wherethepulmonateabstainsfromfeeding.SinceO.tu…  相似文献   
149.
CAS researchers and U.S.collaborators have successfully identified a gene that may hold the key to fight against myeloid leukemia tumor.  相似文献   
150.
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