Wind and fairness in ski jumping: a computer modelling analysis
Wind is closely associated with the discussion of fairness in ski jumping. To counter-act its influence on the jump length, the International Ski Federation (FIS) has introduced a wind compensation approach. We applied three differently accurate computer models of the flight phase with wind (M1, M2, and M3) to study the jump length effects of various wind scenarios. The previously used model M1 is accurate for wind blowing in direction of the flight path, but inaccuracies are to be expected for wind directions deviating from the tangent to the flight path. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Alexander Jung, Wolfram M üller, Manfred Staat Source Type: research
Wide Step Width Reduces Knee Abduction Moment of Obese Adults during Stair Negotiation
An increased likelihood of developing obesity-related knee osteoarthritis may be associated with increased peak internal knee abduction moments (KAbM). Increases in step width (SW) may act to reduce this moment. The purpose of this study was to determine the effects of increased SW on knee biomechanics during stair negotiation of healthy-weight and obese participants. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Derek Yocum, Joshua T. Weinhandl, Jeffrey T. Fairbrother, Songning Zhang Source Type: research
The effect of a maternity support belt on static stability and posture in pregnant and non-pregnant women
Physical and hormonal changes during pregnancy are thought to affect balance and injury risk, with increased numbers of falls being reported. A maternity support belt (MSB) has been suggested to stabilize the pelvis and to enhance balance. The purpose of this study was therefore to investigate the effect of an MSB on postural stability in different trimesters of pregnancy. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Marie Elena Bey, Adamantios Arampatzis, Kirsten Legerlotz Source Type: research
Associations between trunk postural control in walking and unstable sitting at various levels of task demand
Trunk postural control (TPC) has been investigated in several populations and tasks. Previous work observed targeted training of TPC via isolated trunk control tasks may improve performance in other activities (e.g., walking). However, the nature of this relationship remains unknown. We therefore investigated the relationship between TPC, at both the global (i.e., response to finite perturbations) and local (i.e., resistance to infinitesimal perturbations) levels, during walking and unstable sitting, both at varying levels of task demand. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Julian C. Acasio, Courtney M. Butowicz, Pawel R. Golyski, Maury A. Nussbaum, Brad D. Hendershot Tags: Short communication Source Type: research
Kinematics of knees with osteoarthritis show reduced lateral femoral roll-back and maintain an adducted position. A systematic review of research using medical imaging
While several studies describe kinematics of healthy and osteoarthritic knees using the accurate imaging and computer modeling now possible, no systematic review exists to synthesise these data. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Jennie M. Scarvell, Catherine R. Galvin, Diana M. Perriman, Joseph T. Lynch, Robert W.M. van Deursen Source Type: research
Leveling the Playing Field: Evaluation of a Portable Instrument for Quantifying Balance Performance
Balance is a complex, sensorimotor task requiring an individual to maintain the center of gravity within the base of support. Quantifying balance in a reliable and valid manner is essential to evaluating disease progression, aging complications, and injuries in clinical and research settings. Typically, researchers use force plates to track motion of the center of gravity during a variety of tasks. However, limiting factors such as cost, portability, and availability have hindered postural stability evaluation in these settings. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Sutton B. Richmond, Kevin D. Dames, Daniel J. Goble, Brett W. Fling Source Type: research
Compensation for Inertial and Gravity Effects in a Moving Force Platform
Force plates for human movement analysis provide accurate measurements when mounted rigidly on an inertial reference frame. Large measurement errors occur, however, when the force plate is accelerated, or tilted relative to gravity. This prohibits the use of force plates in human perturbation studies with controlled surface movements, or in conditions where the foundation is moving or not sufficiently rigid. Here we present a linear model to predict the inertial and gravitational artifacts using accelerometer signals. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 11, 2018 Category: Biomedical Science Authors: Sandra K. Hnat, Ben J.H. van Basten, Antonie J. van den Bogert Source Type: research
The effect of age and sex on the cervical range of motion – A systematic review and meta-analysis
Cervical-flexibility examination is routinely performed in neck-pain patients. However, diagnosis of cervical-flexibility impairment requires physiological reference values, which vary widely among the population. Although there is a general understanding that the cervical range of motion (RoM) alters with age and sex, the consolidated details of these variations remain lacking. A systematic review and meta-analysis was performed to evaluate the difference of cervical RoM in different age and sex populations. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 7, 2018 Category: Biomedical Science Authors: Fumin Pan, Rizwan Arshad, Thomas Zander, Sandra Reitmaier, Arno Schroll, Hendrik Schmidt Tags: Review Source Type: research
The effect of age and sex on the cervical range of motion A systematic review and meta-analysis
Cervical-flexibility examination is routinely performed in neck-pain patients. However, diagnosis of cervical-flexibility impairment requires physiological reference values, which vary widely among the population. Although there is a general understanding that the cervical range of motion (RoM) alters with age and sex, the consolidated details of these variations remain lacking. A systematic review and meta-analysis was performed to evaluate the difference of cervical RoM in different age and sex populations. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 7, 2018 Category: Biomedical Science Authors: Fumin Pan, Rizwan Arshad, Thomas Zander, Sandra Reitmaier, Arno Schroll, Hendrik Schmidt Tags: Review Source Type: research
Effect of plantarflexion resistance of an ankle-foot orthosis on ankle and knee joint power during gait in individuals post-stroke
Plantarflexion resistance of an ankle-foot orthosis (AFO) plays an important role to prevent foot-drop, but its impact on push-off has not been well investigated in individuals post-stroke. The aim of this study was to investigate the effect of plantarflexion resistance of an articulated AFO on ankle and knee joint power of the limb wearing the AFO in individuals post-stroke. Gait analysis was performed on 10 individuals with chronic stroke using a Vicon 3-dimensional motion capture system and a Bertec split-belt instrumented treadmill. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 4, 2018 Category: Biomedical Science Authors: Toshiki Kobayashi, Michael S. Orendurff, Madeline L. Singer, Fan Gao, Grace Hunt, K. Bo Foreman Tags: Short communication Source Type: research
Spatiotemporal and kinematic changes in gait while carrying an energy harvesting assault pack system
Soldiers are fielded with a variety of equipment including battery powered electronic devices. An energy harvesting assault pack (EHAP) was developed to provide a power source to recharge batteries and reduce the quantity and load of extra batteries carried into the field. Little is known about the biomechanical implications of carrying a suspended-load energy harvesting system compared to the military standard assault pack (AP). Therefore, the goal of this study was to determine the impact of pack type and load magnitude on spatiotemporal and kinematic parameters while walking at 1.34 m/s on an instrumented treadmill at d...
Source: Journal of Biomechanics - May 3, 2018 Category: Biomedical Science Authors: Maria K. Talarico, Courtney A. Haynes, Julianne S. Douglas, Jose Collazo Source Type: research
Mechanical interaction between neighboring muscles in human upper limb: Evidence for epimuscular myofascial force transmission in humans
To confirm the existence of epimuscular myofascial force transmission in humans, this study examined if manipulating joint angle to stretch the muscle can alter the shear modulus of a resting adjacent muscle, and whether there are regional differences in this response. The biceps brachii (BB: manipulated muscle) and the brachialis (BRA: resting adjacent muscle) were deemed suitable for this study because they are neighboring, yet have independent tendons that insert onto different bones. In order to manipulate the muscle length of BB only, the forearm was passively set at supination, neutral, and pronation positions. (Sour...
Source: Journal of Biomechanics - May 3, 2018 Category: Biomedical Science Authors: Yasuhide Yoshitake, Daiki Uchida, Kosuke Hirata, Dean L Mayfield, Hiroaki Kanehisa Source Type: research
Biomechanical characterization of the native porcine aortic root
The objective of this study was to characterize the local structural stiffness of the native aortic root, to create a baseline for understanding how different surgical interventions affect the dynamics of the aortic root. In this acute porcine study (N=10), two dedicated force transducers were implanted to quantify the forces acting on both the annular plane and on the sinotubular junction (STJ). (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 3, 2018 Category: Biomedical Science Authors: T Bechsgaard, T Lindskow, T Lading, JM Hasenkam, DM R øpcke, H Nygaard, P Johansen, SL Nielsen Source Type: research
Decrease in required coefficient of friction due to smaller lean angle during turning in older adults
We investigated age-related differences in the required coefficient of friction (RCOF) during 90 ° turning, the difference of RCOF during step and spin turn, and how affects observed differences. Sixteen healthy young and healthy older adults (eight men and eight women in each group) participated. Participants performed 90° step and spin turns to the right at a self-selected normal speed. Old er adults turned with lower RCOF than the young adults during both step and spin turns. This was associated with reduced mediolateral (ML) RCOF component (RCOFML) for the older adults. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 3, 2018 Category: Biomedical Science Authors: Takeshi Yamaguchi, Ryosuke Okamoto, Kazuo Hokkirigawa, Kei Masani Source Type: research
Effect of severe bioprosthetic valve tissue ingrowth and inflow calcification on valve-in-valve performance
While in-vivo studies clearly demonstrate that supra-annular Valve-in-Valve (ViV) implantation provides the highest probability for optimal post-ViV pressure gradients (PG), there is still no physical insight into explaining anomalies where some supra-annular ViV implantations yield high pressure gradients while some sub-annular implantations yield low pressure gradients. The aim of this study is to explain how severe tissue ingrowth and calcification (TIC) in a surgical aortic valve (SAV) can be one physical mechanism leading to anomalous ViV performance characteristic. (Source: Journal of Biomechanics)
Source: Journal of Biomechanics - May 3, 2018 Category: Biomedical Science Authors: Hoda Hatoum, Jennifer Dollery, Scott M. Lilly, Juan A. Crestanello, Lakshmi Prasad Dasi Source Type: research
