409 research outputs found
3D KINEMATIC ANALYSIS OF THE FRONT HANDSPRING STEPOUT: A PILOT STUDY
This study analyzes the 3d kinematics of the front handspring stepout (FHS) performed by three female gymnasts with different levels of expertise. The purpose was to identify the crucial biomechanical components and how they govern the performance of the athletes. An optoelectronics system (with 6 infrared cameras at 100 Hz) was used to record a specific passive marker-set placed on the subjectsâ bodies. We found that the most important biomechanical parameters were the horizontal components of displacement and velocity
BLOCKING THE QUICK ATTACK IN VOLLEYBALL: A 3D KINEMATIC ANALYSIS
The importance of the volleyball block against the quick attack is more important in the modern volleyball with new scoring system. Two types of tactics are used normally: the Read Block System (RBS) and the Commit Block System (CBS). A preliminary study was conducted to identify variables that quantified the differences between these two techniques. Four young players performing the RBS and the CBS were acquired by means of stereo-photogrammetry and kinematic variables were identified. The quantified analysis confirms coaches experience: in the RBS the hands arrive over the net in a shorter time, the feet start ânaturallyâ wider but the jump performed has a lower height with respect to the CBS. Further longitudinal and transversal studies will be conducted with more subjects of different level and gender
KINEMATICS OF THE SPRINGBOARD PHASE IN YURCHENKO-STYLE VAULTS
The object of this study is the kinematics analysis of the center of mass (COM) in the springboard phase of the Yurchenko-style vault performed by 14 female gymnasts during the 2006 Italian Championship for Clubs. The purpose was to widen the biomechanics knowledge about this phase. Temporal, horizontal and vertical spatial, horizontal and
vertical velocity and bodyâs angle parameters were estimated. A representative kinematics analysis of the Yurchenkoâs springboard phase was compiled based on these
parameters. The results indicated that the gymnasts use the board to avoid a large decrease in the COM horizontal velocity and increase their COM vertical velocity. These
were realizing by a great bodyâs angle at the board impact, reducing the amount of the downward motion in the gathering and maximizing the successive upward lift of the COM
Shot Put: Which Role for Kinematic Analysis?
Background: To understand the technical differences between shot putters of different
ages, this study compared biomechanical parameters of the best senior and youth Italian athletes
and then to worldâclass athletes (WC) assessed in previous investigations. Methods: The best throws
of 16 shot putters [8 Senior (SG) and 8 Youth (YG)] were recorded by video cameras during the
Italian Championshipsâ final and considered for 3D reconstruction. The following parameters were
measured: time of the different throwing phases, shot trajectory, release angle, release velocity, and
the force produced in the final phase. Results: Significant differences between SG and YG were
detected in second single support time (p = 0.015), support time (p = 0.007), total time (p = 0.028) and
in the force produced during the final phase (p < 0.001). A lower level of force, release speed, and a
shorter shot trajectory during the double support were detected in SG compared to WC.
Conclusions: The present study showed that, although the technical performance of all athletes was
similar, some differences exist between YG and SG. The gap between the groups may be partially
explained by the difference in force produced in the final phase of the throw and by a different
interpretation of the technique
Effects of combined strength and endurance training on exercise capacity in kidney transplant cyclists and runners
Introduction: After transplantation, engaging in regular physical activity (PA) or sport is recommended for health. Participation to competitive sports is increasingly common among kidney transplant recipients while little is known on how training affects the physical performance in transplanted athletes. Aim: The purpose of this case study was to assess the effects of a tailored training program on exercise parameters in kidney transplant cyclists (CKTRs) and runners (RKTRs). Methods: Twelve male transplanted athletes were enrolled. The workload at aerobic and anaerobic thresholds, the submaximal aerobic power (V'O2 stage) and rate of perceived exertion (RPE) during an incremental cycling or running test, and the peak instantaneous force (PIF) during a countermovement jump were assessed at baseline (T0) and after 6 months of tailored training (T6) consisting in strength and aerobic exercises. Exercise adherence, blood lipid profile and renal function were also investigated. Results: Eight CKTRs and 4 RKTRs completed the 6-month training period, with a significant increase of training volume (minutes/week). The exercise adherence was met by 90% in both groups. At T6, there were significant (p<0.05) improvements of maximum workload attained, the workload corresponding to the aerobic threshold and PIF, while workloads at anaerobic threshold, V'O2 stage and RPE were unchanged. Blood cholesterol significantly decreased (p<0.01), while the other blood parameters were unchanged. Conclusions: These findings indicate that the combined strength and endurance training is well tolerated and may improve exercise performance in this selected population of KTRs
Renal function and physical fitness after 12-mo supervised training in kidney transplant recipients
To evaluate the effect of a 12-mo supervised aerobic and resistance training, on renal function and exercise capacity compared to usual care recommendations
Longitudinal Analysis of Cardiovascular Risk Factors in Active and Sedentary Kidney Transplant Recipients
Despite the benefits of physical activity on cardiovascular risk in kidney
transplant recipients (KTRs), the long-term effects of exercise have been poorly investigated. This is a
three-year observational study comparing graft function and cardiovascular risk factors in active
KTRs (AKTRs) vs. sedentary KTRs (SKTRs). Methods: KTRs with stable renal function were assigned
to active or sedentary group in relation to the level of daily physical activity based on World Health
Organization (WHO) recommendations (<150 or >150 min/week, respectively). Complete blood
count, renal function indices, lipid profile, blood pressure and anthropometric measures were collected
yearly for an observation period of three years. The comparisons between the two groups were
performed by repeated measures analyses of covariance (ANCOVAs), with age as a covariate. Results:
Fifty-four subjects were included in the study. Thirty of them were identified as AKTRs (M/F 26/4,
aged 45 \ub1 12 years) and 24 as SKTRs (M/F 18/6, aged 51 \ub1 14 years). Baseline characteristics were
similar between the groups except body mass index (BMI) that was significantly higher in SKTRs
(p = 0.043). Furthermore, over the three-year observation period, BMI decreased in AKTRs and
increased in SKTRs (p = 0.006). Graft function was stable in AKTRs, while it showed a decline
over time in SKTRs, as indicated by the rise in serum creatinine levels (p = 0.006) and lower eGFR
(p = 0.050). Proteinuria, glucose and uric acid levels displayed a decrease in AKTRs and an increase
in SKTRs during the three-year period (p = 0.015, p = 0.004 and p = 0.013, respectively). Finally,
concerning lipid profiles, AKTRs had a significant reduction over time of triglycerides levels, which
conversely showed a clinically relevant increase in SKTRs (p = 0.014). Conclusions: Our findings
indicate that regular weekly exercise training may counteract the increased cardiovascular risks and
also prevent graft function decline in KTRs
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