Douglas Gordon Robertson

University of Ottawa · School of Human Kinetics

Background: Previous studies have demonstrated increased medial stresses in knee varus alignment. Selecting a suitable treatment strategy for individuals with knee malalignment should be a priority. Objectives: We aimed to investigate the effects of a 16-week corrective exercise continuum (CEC) program on 3-D joint angles of the dominant and non-do...

Background: Previous studies have demonstrated increased medial stresses in knee varus alignment. Selecting a suitable treatment strategy for individuals with knee malalignment should be a priority. Objectives: We aimed to investigate the effects of a 16-week corrective exercise continuum (CEC) program on 3-D joint angles of the dominant and non...

The association between visual sensory and the asymmetry index of sit-to-stand ground reaction force characteristics is not fully understood. Therefore, the purpose of this study was to investigate asymmetry index of sit-to-stand ground reaction forces, their times–to-peak, vertical loading rate, impulses, and free moment in blind and sighted child...

Gait asymmetry is defined as a loss of perfect agreement between the dominant and non-dominant lower limbs. Conflicting results from gait asymmetry studies may be due to different definitions of asymmetry, different research methods, and/or different variables and formulas used for asymmetry calculation. As a result, this makes it difficult to comp...

Brain injury research in sport employs a variety of physical models equipped with accelerometers. These acceleration signals are commonly processed using filters. The purpose of this research was to determine the effect of applying filters with different cutoff frequencies to the acceleration signals used as input for finite element modeling of the...

Rhythmic behavior in nonlinear systems can be described as limit cycles or attractors. System perturbations may result in shifts between multiple attractors. We investigated individual cycle-to-cycle leg movement kinematics of three pre-walking skilled infant bouncers (10.6 ±0.91 months) during four different spring frequencies (0.9, 1.15, 1.27 and...

Infants explore their environments through repetitive movements that are constrained or facilitated by the environmental context. In this study, we evaluated how skilled bouncers adapted to bouncing in systems with four different spring conditions (natural frequencies of 0.9, 1.15, 1.27 and 1.56 Hz). Trunk kinematics and vertical ground reaction fo...

Lower-back injury from snow shovelling may be related to excessive joint loading. Bent-shaft snow shovels are commonly available for purchase; however, their influence on lower back-joint loading is currently not known. Therefore, the purpose of this study was to compare L5/S1 extension angular impulses between a bent-shaft and a standard straight-...

Research Methods in Biomechanics, Second Edition, demonstrates the range of available research techniques and how to best apply this knowledge to ensure valid data collection. In the highly technical field of biomechanics, research methods are frequently upgraded as the speed and sophistication of software and hardware technologies increase. With t...

Research Methods in Biomechanics, Second Edition, demonstrates the range of available research techniques and how to best apply this knowledge to ensure valid data collection. In the highly technical field of biomechanics, research methods are frequently upgraded as the speed and sophistication of software and hardware technologies increase. With t...

Research Methods in Biomechanics, Second Edition, demonstrates the range of available research techniques and how to best apply this knowledge to ensure valid data collection. In the highly technical field of biomechanics, research methods are frequently upgraded as the speed and sophistication of software and hardware technologies increase. With t...

With this edition colour has been added to the figures and many of the black-and-white pictures have been replaced by colour images. The enhanced figures help to differentiate types vectors and make the analysis of the various problems easier. Furthermore, numerous up-dates have been added throughout the textbook to keep the material current. In ad...

There is a lack of studies investigating gender differences in whole-body kinematics during single-leg landings from increasing vertical heights and horizontal distances. This study determined the main effects and interactions of gender, vertical height, and horizontal distance on whole-body joint kinematics during single-leg landings, and establis...

The central tenet of this study was to develop, validate and apply various individualised 3D musculoskeletal models of the human body for application to single-leg landings over increasing vertical heights and horizontal distances. While contributing to an understanding of whether gender differences explain the higher rate of non-contact anterior c...

抄録 人間の運動中の筋活動を知ることは非常に重要であり，特に無侵襲・無拘束での計測あるいは推定することが非常に期待されている．これまで提案されている筋肉のモデルでは身体の運動制御に大きく関与している拮抗筋や二関節筋が考慮されていないことが多い．そこで，本研究では拮抗筋や二関節筋の影響を考慮した筋骨格モデルを用いて，ジョギング動作において，3次元動作を行っている下肢を2次元レベルへと変換することによって下肢各筋肉の筋力を推定する手法を提案した．また，提案した手法の妥当性を検証するため，実験参加者の下肢各筋肉の表面筋電位を計測しながら，ジョギングを行ってもらい，提案手法を用いて推定される下肢各筋肉の筋活動レベルと表面筋電位の計測結果を比較した．実験結果より，提案した筋活動の推定手法はジョギング動...

This study investigated a musculoskeletal model that includes the function of the antagonistic muscles and biarticular muscles and models muscles acting across the hip, knee and ankle joints, simultaneously. Furthermore, this study can be applied to dynamic motions. One vertical jump trials were conducted to validate the proposed model. Electromyog...

A multidisciplinary design optimization (MDO) approach is proposed to aid in the prediction of non-contact anterior cruciate ligament (ACL) injury mechanisms and risk factors. In this investigation the need for such an approach is argued based on an exhaustive evaluation of diverse factors that cause non-contact ACL injury, and the similarly numero...

To explore manual wheelchair propulsion strategies for ramp ascent and descent in snow and snow-ice-grit conditions. Cross-sectional study. Climatic Engineering and Testing Chamber (Ottawa, Canada). Manual wheelchair users (N=11) who typically self-propel their wheelchair in winter. Ramp ascent and descent at 3 grades (1:10, 1:12, 1:16) and 2 winte...

Angular momentum regulation during a ballet turn as a balance control indicator Coren Walters‐Stewart, Gholamreza Rouhi, D. Gordon E. Robertson In contrast to walking, during which angular momentum is ultimately used for locomotion[1], in ballet, when performing a turn, angular momentum is used to accomplish a rotation. This study characterizes the...

Infants explore their environments often using repetitive movements of multiple degrees of freedom to create a motor sequence. Previous research suggests that infants suspended in a commercial spring-mounted harness bounce at two frequencies using distinct mechanisms of control (Vallis, 1998). We determined how typically developing infants bounced...

The purpose of this research was to determine the functions of the gluteus maximus, biceps femoris, semitendinosus, rectus femoris, vastus lateralis, soleus, gastrocnemius, and tibialis anterior muscles about their associated joints during full (deep-knee) squats. Muscle function was determined from joint kinematics, inverse dynamics, electromyogra...

This paper involved a biomechanical analysis of lower limb joint coordination during hula hooping. A lower extremity inverse dynamics model that incorporated kinematic input and force platform data was developed to compute the angular velocities, moments about and powers produced at the lower extremity joints. The abductor moments and powers were d...

The activity of descending stairs increases loading at the joints of the lower extremities as compared to walking, which may cause discomfort and or difficulties in completing the task. This study compared and contrasted the kinematics and kinetics of both forwards and backwards stair descent to those of level walking. We compared the support momen...

In hula hooping, organized motions of the body keep the hoop in stable oscillatory motion parallel to the ground. We examined the hypothesis that the multiple degrees of freedom (DF) of the lower limbs in producing the oscillations are resolved into a few control DF. The KarhunenLoè ve decomposition was applied to the kinematics of the lower limbs...

The purpose of this study was to quantify the ground reaction forces, moments of forces and moment powers during the landing from the ballet jump called the grand jeté. In addition, the flight phase was examined to determine whether the illusion of linear motion occurred. Laws (2002) has stated that it is possible for dancers to give the illusion o...

Research Methods in Biomechanics, Second Edition, demonstrates the range of available research techniques and how to best apply this knowledge to ensure valid data collection. In the highly technical field of biomechanics, research methods are frequently upgraded as the speed and sophistication of software and hardware technologies increase. With t...

PREFACE The field of biomechanics continues to change rapidly. At the time the first edition was published videographic analysis was displacing 16-mm cinefilm motion analysis. Now the biomechanist has a variety of systems for quantifying human motion from analog video (such as VHS, Beta, SVHS) to digital video (DV) to direct capture by DV cameras,...

Research Methods in Biomechanics, Second Edition, demonstrates the range of available research techniques and how to best apply this knowledge to ensure valid data collection. In the highly technical field of biomechanics, research methods are frequently upgraded as the speed and sophistication of software and hardware technologies increase. With t...

Research Methods in Biomechanics, Second Edition, demonstrates the range of available research techniques and how to best apply this knowledge to ensure valid data collection. In the highly technical field of biomechanics, research methods are frequently upgraded as the speed and sophistication of software and hardware technologies increase. With t...

Two methods for calculating internal work-the absolute work method, based on changes in mechanical energy, and the absolute power method, based on the powers produced by the joint moments of force-were compared. The results from both methods were normalized to body mass and running speed to obtain the 'internal biomechanical cost' (IBC). The IBCs o...

For many years the Butterworth lowpass filter has been used to smooth many kinds of biomechanical data, despite the fact that it is underdamped and therefore overshoots and/or undershoots data during rapid transitions. A comparison of the conventional Butterworth filter with a critically damped filter shows that the critically damped filter not onl...