The Effect of Muscular Pre-Tensing on the Sprint Start

2006 ◽  
Vol 22 (3) ◽  
pp. 194-201 ◽  
Author(s):  
Marcos Gutiérrez-Dávila ◽  
Jesús Dapena ◽  
José Campos
Keyword(s):  
Body Weight ◽  
Center Of Mass ◽  
Horizontal Velocity ◽  
Acceleration Phase ◽  
Performance Change ◽  
Significant Difference

Pre-tensed and conventional starts that exert, respectively, large and small forces against the starting blocks in the “set” position (0.186 vs. 0.113 N per newton of body weight) were analyzed. The starts were videotaped, and the horizontal forces exerted on feet and hands were obtained from separate force plates. In the pre-tensed start, the legs received larger forward impulses early in the acceleration (0.18 vs. 0.15 N·s per kilogram of mass in the first 0.05 s), but the hands received larger backward impulses (–0.08 vs. –0.04 N·s·kg–1). At the end of the acceleration phase, there was no significant difference in horizontal velocity between the two types of start and only trivial differences in the center of mass positions. The results did not show a clear performance change when the feet were pressed hard against the blocks while waiting for the gun.

scholarly journals Análisis de la contribución segmentaria en el rendimiento de las salidas de velocidad. (Analysis of the segmental contribution in sprint start performance)

Retos ◽  
2021 ◽  
Vol 43 ◽  
pp. 988-995
Author(s):  
Carmen Gutiérrez-Cruz ◽  
Marcos Gutiérrez-Dávila ◽  
Jose Campos-Granell
Keyword(s):  
Sagittal Plane ◽  
Performance Indicator ◽  
Center Of Mass ◽  
Horizontal Displacement ◽  
Video Camera ◽  
Horizontal Velocity ◽  
Acceleration Phase ◽  
Body Segments ◽  
Reaction Forces ◽  
Calculation System

  En este estudio se ha aplicado un sistema de cálculo para examinar la contribución de cinco grupos de segmentos corporales al desplazamiento horizontal del CM en las salidas de tacos y explorar su relación con la velocidad horizontal del CM al final de 0.1s y 0.312s de la fase de aceleración. Han participado 20 velocistas con récord personal en 100 m de 11,05±0,31s. Se registraron las fuerzas horizontales de reacción mediante dos plataformas de fuerzas sincronizadas a una cámara de vídeo que registraba el plano sagital del movimiento. La contribución de las piernas al final de la fase de aceleración fue del 91.2±2.4 % y la pierna libre del 8.1±1.0 %. El tronco+cabeza es el primer grupo de segmentos que comienza a contribuir al desplazamiento horizontal del CM, alcanzando el 39.3 ± 24.3 % en los primeros 0.1s. Su rápida contribución hacia delante provoca una fuerza reactiva hacia atrás que podría estar relacionada con una dorsiflexión de los tobillos de 8º±3º y 9º±3º, pierna retrasada y adelantada, respectivamente. La contribución temprana de la cabeza+tronco se ha correlacionado positivamente con la velocidad horizontal al final de la fase de aceleración (r=0.622, p=0.003), lo que confirma su importancia como indicador de rendimiento en las salidas de tacos. Abstract. In this study, a calculation system has been applied to examine the contribution of five groups of body segments to the horizontal displacement of the Center of Mass (CM) in block starts and to explore their relationship with the horizontal velocity of the CM at the end of 0.1s and 0.312s of the acceleration phase. Twenty sprinters with a personal record in 100 m of 11.05 ± 0.31s have participated. The horizontal reaction forces were recorded using two force platforms synchronized to a video camera that recorded the sagittal plane of motion. The contribution of the legs at the end of the acceleration phase was 91.2 ± 2.4% and the free leg was 8.1 ± 1.0%. The trunk + head is the first group of segments that begins to contribute to the horizontal displacement of the CM, reaching 39.3 ± 24.3% in the first 0.1s. His quick forward contribution causes a reactive backward force that could be related to an ankle dorsiflexion of 8º ± 3º and 9º ± 3º, back and front leg, respectively. The early contribution of the head + trunk has been positively correlated with the horizontal velocity at the end of the acceleration phase (r = 0.622, p = 0.003), which confirms its importance as a performance indicator in block starts.

scholarly journals Lean body weight versus total body weight to calculate the iodinated contrast media volume in abdominal CT: a randomised controlled trial

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Moreno Zanardo ◽  
Fabio Martino Doniselli ◽  
Anastassia Esseridou ◽  
Massimiliano Agrò ◽  
Nicol Antonina Rita Panarisi ◽  
...  
Keyword(s):  
Body Weight ◽  
Contrast Media ◽  
Controlled Trial ◽  
Total Body Weight ◽  
Lean Body Weight ◽  
Iodinated Contrast Media ◽  
Abdominal Ct ◽  
Iodinated Contrast ◽  
Significant Difference ◽  
Total Body

Abstract Objectives Iodinated contrast media (ICM) could be more appropriately dosed on patient lean body weight (LBW) than on total body weight (TBW). Methods After Ethics Committee approval, trial registration NCT03384979, patients aged ≥ 18 years scheduled for multiphasic abdominal CT were randomised for ICM dose to LBW group (0.63 gI/kg of LBW) or TBW group (0.44 gI/kg of TBW). Abdominal 64-row CT was performed using 120 kVp, 100–200 mAs, rotation time 0.5 s, pitch 1, Iopamidol (370 mgI/mL), and flow rate 3 mL/s. Levene, Mann–Whitney U, and χ2 tests were used. The primary endpoint was liver contrast enhancement (LCE). Results Of 335 enrolled patients, 17 were screening failures; 44 dropped out after randomisation; 274 patients were analysed (133 LBW group, 141 TBW group). The median age of LBW group (66 years) was slightly lower than that of TBW group (70 years). Although the median ICM-injected volume was comparable between groups, its variability was larger in the former (interquartile range 27 mL versus 21 mL, p = 0.01). The same was for unenhanced liver density (IQR 10 versus 7 HU) (p = 0.02). Median LCE was 40 (35–46) HU in the LBW group and 40 (35–44) HU in the TBW group, without significant difference for median (p = 0.41) and variability (p = 0.23). Suboptimal LCE (< 40 HU) was found in 64/133 (48%) patients in the LBW group and 69/141 (49%) in the TBW group, but no examination needed repeating. Conclusions The calculation of the ICM volume to be administered for abdominal CT based on the LBW does not imply a more consistent LCE.

Impact of Weight-Band Dosing of Tinzaparin for Venous Thromboembolism Prophylaxis on Persistent Wound Drainage in Adult Patients Undergoing Hip and Knee Arthroplasty

2021 ◽  
pp. 106002802110242
Author(s):  
Cassandra Cooper ◽  
Ouida Antle ◽  
Jennifer Lowerison ◽  
Deonne Dersch-Mills ◽  
Ashley Kenny
Keyword(s):  
Body Weight ◽  
Venous Thromboembolism ◽  
Knee Arthroplasty ◽  
Total Joint Arthroplasty ◽  
Joint Arthroplasty ◽  
Thromboembolism Prophylaxis ◽  
Wound Drainage ◽  
Increased Risk ◽  
Significant Difference ◽  
The Impact

Background: Persistent wound drainage and venous thromboembolism (VTE) are potential complications of total joint arthroplasty, and these risks can be challenging to balance in clinical practice. Anecdotal observation has suggested that following joint arthroplasty, persistent wound drainage occurs more frequently with higher body weight and higher doses of tinzaparin when compared with lower body weight and lower doses of tinzaparin. Objective: The overall purpose of this study was to describe the impact of a tinzaparin weight-band dosing table for VTE prophylaxis on wound healing, thrombosis, and bleeding outcomes in patients undergoing total joint arthroplasty. Methods: This retrospective chart review included patients who underwent total hip or knee arthroplasty and received tinzaparin for thromboprophylaxis per their weight-banding category. The primary outcome was the incidence of persistent wound drainage. Secondary outcomes include the occurrence of VTE and clinically important bleeding during hospital admission. Results: A total of 231 patients were included in the analysis. There was no significant difference in persistent wound drainage between the 3 weight categories, and there were no differences in rates of VTE or clinically important bleeding. Concurrent use of low-dose acetylsalicylic acid was associated with a 3-fold increased risk of persistent wound drainage (risk ratio = 3.35; 95% CI = 2.14-5.24; P = 0.00003). Conclusion and Relevance: In joint arthroplasty patients, we observed no significant difference in rates of persistent wound drainage between various weight categories receiving different weight-banded doses of tinzaparin. Our results do not suggest that the current weight-band dosing table for tinzaparin needs to be adjusted to optimize patient outcomes.

scholarly journals In Vivo Radioprotective Activity of Cell-Permeable Bifunctional Antioxidant Enzyme GST-TAT-SOD against Whole-Body Ionizing Irradiation in Mice

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Jianru Pan ◽  
Huocong He ◽  
Ying Su ◽  
Guangjin Zheng ◽  
Junxin Wu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Antioxidant Activity ◽  
Body Weight ◽  
Whole Body ◽  
White Pulp ◽  
Radioprotective Activity ◽  
Significant Difference ◽  
Wbc Count

GST-TAT-SOD was the fusion of superoxide dismutase (SOD), cell-permeable peptide TAT, and glutathione-S-transferase (GST). It was proved to be a potential selective radioprotector in vitro in our previous work. This study evaluated the in vivo radioprotective activity of GST-TAT-SOD against whole-body irradiation. We demonstrated that intraperitoneal injection of 0.5 ml GST-TAT-SOD (2 kU/ml) 2 h before the 6 Gy whole-body irradiation in mice almost completely prevented the splenic damage. It could significantly enhance the splenic antioxidant activity which kept the number of splenic white pulp and consequently resisted the shrinkage of the spleen. Moreover, the thymus index, hepatic antioxidant activity, and white blood cell (WBC) count of peripheral blood in irradiated mice pretreated with GST-TAT-SOD also remarkably increased. Although the treated and untreated irradiated mice showed no significant difference in the growth rate of animal body weight at 7 days postirradiation, the highest growth rate of body weight was observed in the GST-TAT-SOD-pretreated group. Furthermore, GST-TAT-SOD pretreatment increased resistance against 8 Gy whole-body irradiation and enhanced 30 d survival. The overall effect of GST-TAT-SOD seemed to be a bit more powerful than that of amifostine. In conclusion, GST-TAT-SOD would be a safe and potentially promising radioprotector.

Variation in kinematics and dynamics of the landing flights of pigeons on a novel perch

1998 ◽  
Vol 201 (24) ◽  
pp. 3309-3316 ◽  
Author(s):  
P. R. Green ◽  
P. Cheng
Keyword(s):  
Body Weight ◽  
Kinetic Energy ◽  
Horizontal Velocity ◽  
Maximum Force ◽  
Kinematics And Dynamics ◽  
Video Recordings

Pigeons made 10 flights to a novel perch. Kinematic measurements of these flights were obtained from video recordings, and the forces exerted on the perch on each landing were measured. There was wide variation(20-fold range) in the kinetic energy of the pigeons just before landing,arising almost entirely from variation in horizontal velocity. The maximum force exerted on the perch varied in magnitude from approximately twice to eight times the pigeons' body weight, and in direction from 40 to 90 below the horizontal. In landings with high final kinetic energy, the maximum force exerted on the perch was larger and was applied at a shallower angle than in those with low final kinetic energy. Landing flights with high final kinetic energy showed straighter trajectories and a larger peak deceleration during the last 300 ms of approach flight than those with low final kinetic energy, which had downward-curving trajectories and a more prolonged and steady pattern of deceleration. Mean final kinetic energy was lower in the first two landings made on the perch than in subsequent landings, indicating that pigeons are more likely to adopt a slow,downward-curving approach to a novel perch and a fast, straight approach to a familiar one.

scholarly journals Regression of gestational diabetes induced cardiomegaly in offspring of diabetic rat

2009 ◽  
Vol 24 (4) ◽  
pp. 251-255 ◽  
Author(s):  
Honório Sampaio Menezes ◽  
Cláudio Galeano Zettler ◽  
Alice Calone ◽  
Jackson Borges Corrêa ◽  
Carla Bartuscheck ◽  
...  
Keyword(s):  
Body Weight ◽  
Wistar Rats ◽  
Weight Ratio ◽  
Diabetic Rats ◽  
Heart Weight ◽  
Diabetic Rat ◽  
Control Group ◽  
Computer Assisted ◽  
Significant Difference ◽  
Levene Test

PURPOSE: To compare body weight and length, heart weight and length, heart-to-body weight ratio, glycemia, and morphometric cellular data of offspring of diabetic rats (ODR) and of normal rats (control). METHODS: Diabetes was induced in 3 pregnant Wistar rats, bearing 30 rats, on the 11th day after conception by intraperitoneal injection of 50 mg/kg of streptozotocin. Six normal pregnant Wistar rats, bearing 50 rats, made up the control group. Morphometric data were obtained using a scale for the weight, length, heart and body measurements. Morphometric cellular data were obtained by a computer assisted method applied to the measurements of myocytes. Statistical analysis utilized Student's t-test, ANOVA and Levene test. RESULTS: Control offspring had greater mean body weight and length than offspring of diabetic rats (p < 0.001). Heart weight and length and heart-to-body ratios of newborn rats differed between groups at birth (p < 0.001), but showed no difference at 21 days. Mean nuclei area and perimetric value of the myocytes decrees throughout the first 21 days of life (p < 0.01) in the diabetic group. CONCLUSIONS: Heart hypertrophy on the offspring of diabetic rats at birth was demonstrated by the significant difference between the groups. After the eleventh day, no difference was found, which confirmed regression of cardiomegaly. The significant difference between the first and the 21th day of life, for nuclei area feature, demonstrate regression of cardiac hypertrophy in the offspring of diabetic rats.

A study on the safety evaluation of buphrenorphine administered through an autoinjector compared with manual injection using haematological and biochemical variables in rats

2016 ◽  
Vol 36 (9) ◽  
pp. 901-909 ◽  
Author(s):  
D Sheela ◽  
R Vijayaraghavan ◽  
S Senthilkumar
Keyword(s):  
Body Weight ◽  
Research Work ◽  
Safety Evaluation ◽  
Weight Ratio ◽  
The Body ◽  
Control Group ◽  
Body Weight Ratio ◽  
Significant Difference ◽  
Manual Group ◽  
Significant Change

Buprenorphine drug cartridge was made for autoinjector device for use in emergency and critical situations to reduce the morbidity and mortality. Water-filled cartridges were prepared and buprenorphine was injected aseptically in the cartridge, to make 0.05 and 0.10 mg/mL. Rats were injected intraperitoneally, buprenorphine (0.3 and 0.6 mg/kg), repeatedly with the autoinjector and compared with manual injection (7 days and 14 days) using various haematological and biochemical parameters. No significant change was observed in the body weight, organ to body weight ratio and haematological variables in any of the experimental groups compared with the control group. Except serum urea and aspartate aminotransferase, no significant change was observed in glucose, cholesterol, triglycerides, bilirubin, protein, albumin, creatinine, uric acid, alanine aminotransferase, gamma glutamyltransferase and alkaline phosphatase. The autoinjectors deliver the drugs with spray effect and force for faster absorption. In the present study, the autoinjector meant for intramuscular injection was injected intraperitoneally in rats, and the drug was delivered with force on the vital organs. No significant difference was observed in the autoinjector group compared to the manual group showing tolerability and safety of the buphrenorphine autoinjector. This study shows that buprenorphine autoinjector can be considered for further research work.

Azole-resistant and -susceptible Aspergillus fumigatus isolates show comparable fitness and azole treatment outcome in immunocompetent mice

2017 ◽  
Vol 56 (6) ◽  
pp. 703-710
Author(s):  
Michaela Lackner ◽  
Günter Rambach ◽  
Emina Jukic ◽  
Bettina Sartori ◽  
Josef Fritz ◽  
...  
Keyword(s):  
Body Weight ◽  
Aspergillus Fumigatus ◽  
Severe Disease ◽  
Weight Ratio ◽  
Clinical Parameters ◽  
Fitness Advantage ◽  
Significant Difference ◽  
Immunocompetent Mice

Abstract No data are available on the in vivo impact of infections with in vitro azole-resistant Aspergillus fumigatus in immunocompetent hosts. Here, the aim was to investigate fungal fitness and treatment response in immunocompetent mice infected with A. fumigatus (parental strain [ps]) and isogenic mutants carrying either the mutation M220K or G54W (cyp51A). The efficacy of itraconazole (ITC) and posaconazole (PSC) was investigated in mice, intravenously challenged either with a single or a combination of ps and mutants (6 × 105 conidia/mouse). Organ fungal burden and clinical parameters were measured. In coinfection models, no fitness advantage was observed for the ps strain when compared to the mutants (M220K and G54W) independent of the presence or absence of azole-treatment. For G54W, M220K, and the ps, no statistically significant difference in ITC and PSC treatment was observed in respect to fungal kidney burden. However, clinical parameters suggest that in particular the azole-resistant strain carrying the mutation G54W caused a more severe disease than the ps strain. Mice infected with G54W showed a significant decline in body weight and lymphocyte counts, while spleen/body weight ratio and granulocyte counts were increased. In immunocompetent mice, in vitro azole-resistance did not translate into therapeutic failure by either ITC or PSC; the immune system appears to play the key role in clearing the infection.

scholarly journals An exertion of enhance milk yield of native Pabna cattle through using different types of calcium salt of fatty acid

2018 ◽  
Vol 15 (2) ◽  
pp. 137-146 ◽  
Author(s):  
D Yeasmin ◽  
N Islam ◽  
NR Sarker ◽  
N Huda ◽  
A Habib ◽  
...  
Keyword(s):  
Body Weight ◽  
Fatty Acid ◽  
Milk Yield ◽  
Calcium Salt ◽  
Bos Indicus ◽  
Mustard Oil ◽  
Initial Body Weight ◽  
Significant Difference ◽  
Different Types ◽  
Concentrate Mixture

Keeping consideration on increasing quality milk production through addition of conventional fat, an experiment accords CRD design was conducted at Bangladesh Livestock Research Institute, Savar, Dhaka for a period of 30 days including 5 days of digestibility trial. Twenty lactating Pabna cattle of average 250.1 ± 13.64 kg (Bos indicus) of initial body weight with average milk yield of 2.88 ± 0.38 kg were selected and divided into four groups randomly having five cows in each. The imposed treatments were T0, T1, T2, and T3; in where To= German grass + Concentrate mixture without Ca salt of fatty acid + 2.5 % DCP, T1= German grass + Concentrate mixture + 2.5 % soybean based Ca salt of fatty acid, T2= German grass + Concentrate mixture + 2.5 % mustard based Ca salt of fatty acid and T3= German grass + Concentrate mixture + 2.5% palm-oil based Ca salt of fatty acid. The result showed that, calcium salt of fatty acid influenced to increase of milk yield significantly among (P<0.001) the treatments; in where highest yield gained in T1 (3.53 kg d-1) followed by T2, T0 and T3 (3.33, 2.44 and 2.24, respectively). Besides this, all other parameters analytically examined in this experiment i.e. intake, apparent digestibility, gained body weight and chemical composition of milk showed non-significant difference among the treatments. From the analytical value and discussion, it may be suggested that, calcium salt of fatty acid formulated from soybean oil or mustard oil could be used for enhancing better quality milk yield.SAARC J. Agri., 15(2): 137-146 (2017)

scholarly journals THE EFFECT OF DEXAMETHASONE ON SPERMATOGONIUM AND SERTOLI CELL OF IPSILATERAL TESTIS IN UNILATERAL TESTICULAR TORSION WISTAR RAT

2018 ◽  
Vol 25 (2) ◽  
Author(s):  
Ferdyan Rachmat Efendi ◽  
Johan Renaldo ◽  
Tarmono Djojodimedjo
Keyword(s):  
Body Weight ◽  
Sertoli Cell ◽  
Sertoli Cells ◽  
Testicular Torsion ◽  
Wistar Rat ◽  
Male Rats ◽  
Sham Operation ◽  
Group I ◽  
Significant Difference ◽  
The Mean

Objective: To investigate the effect of dexamethasone on spermatogonium and sertoli cell of ipsilateral testis in unilateral testicular torsion strain wistar rat. Material & Method: Experimental study with post-test only control group design. The present  study was conducted on 30 Wistar male rats aged 10 – 12 weeks grouped into 5 groups. Group I was the normal/sham operation group (KN), group II was left testicular torsion for 4 hours group and followed  by manual detorsion  (K1), group III was left testicular torsion for 10 hours group and followed  by manual detorsion (K2),  group IV was left testicular torsion for 4 hours group and given dexamethasone 10 mg/kg body weight subcutaneously 30 minutes before manual etorsion (D1), and group V was left testicular torsion for 10 hours group and  given dexamethasone 10 mg/kg body weight subcutaneously 30 minutes before manual detorsion. All rats had left orchidectomy 4 hours after detorsion. The number of spermatogonium and sertoli cells were counted in histological seminiferous tubular testis that have obtained Haematoxylin Eosin staining. Data were analyzed by ANNOVA followed by Post Hoc Tukey for spermatogonium and Kruskal Wallis followed by Mann Whitney test for sertoli cell. Differences were considered significant at p <0.05. Results: There was significant difference in the mean number of spermatogonium between K1 & D1 group. Otherwise, there was no significant difference in the mean number of spermatogonium between K2 & D2. There was significant difference in the mean number of Sertoli cells between K1 & D1 group, likewise that between K2 & D2 group. Conclusion: These results suggest that dexamethasone has protective effect in spermatogonium and sertoli cell in testicular torsion for 4 hours.

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