LOWER EXTREMITY KINEMATICS DURING HIGH SPEED TREADMILL SPRINTING OVER A RANGE OF VELOCITIES

A kinematic analysis of selected variables was completed during high speed treadmill sprinting over a range of velocities. Six power/speed athletes experienced at sprinting on a treadmill performed trials at 60%, 70%, 80%, 90%, and 95% of their previous individual maximum velocity, with video data collected in the sagittal plane at 60 Hz. The results indicated that there were significant differences among the variables studied, particularly at slower velocities. Peak hip extension and peak knee flexion showed no differences across test conditions. As the treadmill velocity approached a maximum, mechanical breakdown was seen in a decreased maximum hip flexion angle and peak hip flexion angular velocity, suggesting that velocities greater than 90% velocity should be used selectively during treadmill training

THE IMPACT OF THERAPEUTIC ANKLE TAPING ON THE KINEMATICS OF THE LOWER EXTREMITY WHILE RUNNING

Overpronation is a misalignment of the calcaneus resulting from flattening of the medial longitudinal arch, which may lead to an overuse injury in runners. It is suggested that taping may control the position of the calcaneus to correct foot pathologies associated with overpronation. This pilot study explored the effect of ankle taping on the kinematics of the lower extremity while running. Fifteen healthy participants ran on a treadmill with a Kinesio Tape®, Leuko Tape®, and a no tape condition while being video recorded for 3D analysis. No significant changes in the selected lower extremity kinematic variables were seen among the tape and no tape conditions. Participants demonstrated an average Foot Posture Index score of 2.2±1.5, which is considered neutral. Ankle taping may be more beneficial in altering lower extremity kinematics in runners with higher values of pronation and at faster running speeds

An advanced computational intelligent framework to predict shear sonic velocity with application to mechanical rock classification

Shear sonic wave velocity (Vs) has a wide variety of implications, from reservoir management and development to geomechanical and geophysical studies. In the current study, two approaches were adopted to predict shear sonic wave velocities (Vs) from several petrophysical well logs, including gamma ray (GR), density (RHOB), neutron (NPHI), and compressional sonic wave velocity (Vp). For this purpose, five intelligent models of random forest (RF), extra tree (ET), Gaussian process regression (GPR), and the integration of adaptive neuro fuzzy inference system (ANFIS) with differential evolution (DE) and imperialist competitive algorithm (ICA) optimizers were implemented. In the first approach, the target was estimated based only on Vp, and the second scenario predicted Vs from the integration of Vp, GR, RHOB, and NPHI inputs. In each scenario, 8061 data points belonging to an oilfield located in the southwest of Iran were investigated. The ET model showed a lower average absolute percent relative error (AAPRE) compared to other models for both approaches. Considering the first approach in which the Vp was the only input, the obtained AAPRE values for RF, ET, GPR, ANFIS + DE, and ANFIS + ICA models are 1.54%, 1.34%, 1.54%, 1.56%, and 1.57%, respectively. In the second scenario, the achieved AAPRE values for RF, ET, GPR, ANFIS + DE, and ANFIS + ICA models are 1.25%, 1.03%, 1.16%, 1.63%, and 1.49%, respectively. The Williams plot proved the validity of both one-input and four-inputs ET model. Regarding the ET model constructed based on only one variable,Williams plot interestingly showed that all 8061 data points are valid data. Also, the outcome of the Leverage approach for the ET model designed with four inputs highlighted that there are only 240 "out of leverage" data sets. In addition, only 169 data are suspected. Also, the sensitivity analysis results typified that the Vp has a higher effect on the target parameter (Vs) than other implemented inputs. Overall, the second scenario demonstrated more satisfactory Vs predictions due to the lower obtained errors of its developed models. Finally, the two ET models with the linear regression model, which is of high interest to the industry, were applied to diagnose candidate layers along the formation for hydraulic fracturing. While the linear regression model fails to accurately trace variations of rock properties, the intelligent models successfully detect brittle intervals consistent with field measurements

THE EFFECTS OF KNEE BRACING ON REACTIVE AGILITY PERFORMANCE AND EMG ACTIVITY IN HEALTHY SOCCER PLAYERS – A PILOT STUDY

This pilot study examined differences between braced and non-braced soccer players on measures of reactive agility time and electromyographic (EMG) activity of the gluteus medius (GM), biceps femoris (BF), and vastus lateralis (VL) muscles during the acceleration and change of direction phases of the Y-shaped reactive agility test. Twenty-four participants completed a Y-shaped reactive agility test under two conditions including wearing no knee brace and wearing a Playmaker II knee brace (DonJoy®, Lewisville, Texas) on their dominant leg. Although higher muscle activation was found in the GM and BF muscles during the change of direction phase compared to the acceleration phase, bracing did not statistically significantly affect agility time and EMG muscle activity. This outcome suggests that preventative bracing does not seem to hinder an athlete’s performance

The Effect of Ankle Taping on the Kinematics of the Lower Extremity While Running on Level, Inclined, and Declined Slopes

Topics in Exercise Science and Kinesiology Volume 2: Issue 1, Article 8, 2021. Therapeutic taping is often prescribed as a treatment for various overuse injuries in the lower extremity. Researchers believe that taping may control the position and alter alignment of the calcaneus to correct foot pathologies when applied to the ankle in runners, however, the utility and specific mechanical effects of different taping techniques remains unclear. The purpose of this study was to explore the effect of ankle taping (no tape (NT), Kinesiotape® (KT), or Leukotape® (LT)) across different slope conditions (level, inclined, and declined) on the kinematics of the hip, knee, and ankle joints. Forty healthy participants (males=18, females=22) ran on a treadmill under different taping and slope conditions. Lower extremity kinematics at the hip, knee, and ankle were analyzed using a Contemplas Templo® 3D motion capture system. Data were analyzed using two-way repeated measures analyses of variance (ANOVAs; p\u3c0.05) for each kinematic variable, respectively. Data analysis revealed no significant interactions effects between taping conditions and slope on kinematics measured across joints. The results, however, revealed a significant main effect for type of tape for peak knee flexion angle during the stance phase of running with the application of LT, which produced less knee flexion when compared to KT. The results also revealed a significant main effect regarding slope conditions which identified an increase in stride length (SL) while running on a declined slope compared to an inclined slope. Finally, a significant main effect concerning slope conditions was found which identified a decrease in stride frequency (SF) while running on a declined slope compared to a level and inclined slope. The results of this study suggested that the application of LT affected knee flexion during the stance phase of running. This tape outcome may have implications for clinicians, coaches, and patients because they suggest that the application of LT may potentially reduce the risk of overuse injury due to repetitive flexion at the knee joint while running. Additionally, slope outcomes suggest that increased SL and decreased SF may reduce impact forces while running on a declined slope. Future research is required to further explore these preliminary results

THE IMPACT OF THERAPEUTIC ANKLE TAPING AND FOOT POSTURE ON THE KINEMATICS OF THE KNEE AND ANKLE WHILE RUNNING

Overpronation is a misalignment of the calcaneus, contributing to overuse injuries in runners. Taping may control the position of the calcaneus to correct foot pathologies associated with overpronation. The purpose of this study was to explore the effect of therapeutic ankle taping and foot posture on the kinematics of the knee and ankle during running in participants with neutral and pronated foot types. Forty healthy participants ran on a treadmill with the application of Kinesio Tape®, Leuko Tape®, and no tape. A significant main effect for foot posture indicated that participants with a pronated foot type (p=.03) ran with a decreased amount of plantarflexion at the toe off phase of running when compared to a neutral foot type for all taping conditions. As plantarflexion occurs at toe off to propel the runner to the swing phase, a more rigid taping technique may be beneficial to provide support to the calcaneus

Derivation of tropospheric methane from TCCON CH₄ and HF total column observations

The Total Carbon Column Observing Network (TCCON) is a global ground-based network of Fourier transform spectrometers that produce precise measurements of column-averaged dry-air mole fractions of atmospheric methane (CH₄). Temporal variability in the total column of CH₄ due to stratospheric dynamics obscures fluctuations and trends driven by tropospheric transport and local surface fluxes that are critical for understanding CH₄ sources and sinks. We reduce the contribution of stratospheric variability from the total column average by subtracting an estimate of the stratospheric CH₄ derived from simultaneous measurements of hydrogen fluoride (HF). HF provides a proxy for stratospheric CH₄ because it is strongly correlated to CH₄ in the stratosphere, has an accurately known tropospheric abundance (of zero), and is measured at most TCCON stations. The stratospheric partial column of CH₄ is calculated as a function of the zonal and annual trends in the relationship between CH₄ and HF in the stratosphere, which we determine from ACE-FTS satellite data. We also explicitly take into account the CH₄ column averaging kernel to estimate the contribution of stratospheric CH₄ to the total column. The resulting tropospheric CH₄ columns are consistent with in situ aircraft measurements and augment existing observations in the troposphere

KINEMATIC ANALYSIS OF MEN BOBSLED PUSH STARTS

The purpose of this study was to provide a descriptive analysis of selected kinematic variables associated with the push start for brakemen in the two-man bobsled. Eleven male bobsledders served as subjects for this study. The subjects were videotaped at 120 Hz during competition at the Lake Placid, NY bobsled track as they were competing for positions on the men’s 2004 National Bobsled Team. Selected groups of variables measured at specific events in this study included step length, frequency, and foot contact time; COM velocity; and trunk, knee, and elbow angles. A relationship of 0.63 was determined between start time and finish time; an exploratory correlational analysis between start time and COM velocity at 2nd step take-off (TO) was -0.63. Start time is of critical importance in determining final race time

Intelligent wearable allows out-of-the-lab tracking of developing motor abilities in infants

Peer reviewe

First data set of H₂O/HDO columns from the Tropospheric Monitoring Instrument (TROPOMI)

This paper presents a new data set of vertical column densities of the water vapour isotopologues H2O and HDO retrieved from short-wave infrared (2.3 μm) reflectance measurements by the Tropospheric Monitoring Instrument (TROPOMI) aboard the Sentinel-5 Precursor satellite. TROPOMI features daily global coverage with a spatial resolution of up to 7 km × 7 km. The retrieval utilises a profile-scaling approach. The forward model neglects scattering, thus strict cloud filtering is necessary. For validation, recent ground-based water vapour isotopologue measurements by the Total Carbon Column Observing Network (TCCON) are employed. A comparison of TCCON δD with measurements by the project Multi-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA) for data prior to 2014 (where MUSICA data is available) shows a bias in TCCON δD estimates. As TCCON HDO is currently not validated, an overall correction of recent TCCON HDO data is derived based on this finding. The agreement between the corrected TCCON measurements and collocated TROPOMI observations is good with an average bias of (0.02 ± 2) · 1021 molec cm−2 in H2O and (−0.3 ± 7) · 1017 molec cm−2 in HDO, which corresponds to a bias of (−12 ± 17) ‰ in a posteriori δD. The use of the data set is demonstrated with a case study of a blocking anticyclone in northwestern Europe in July 2018 using single overpass data