Foam rolling improvements in passive hip flexion last up to 60-minutes in ice hockey players.

Background: Ice hockey players often lack hip mobility which may be attributed to excessive time spent in a flexed position during competition and the intensive use of hip external rotators and extensors. Previous investigations demonstrate that foam rolling increases range-of-motion in healthy populations. It is unclear whether such benefits occur in athletes with chronic hip tightness.

Effect of movement speed on trunk and hip exercise performance.

The influence of speed on trunk exercise technique is poorly understood. The aim of this study was to analyse the effect of movement speed on the kinematics and kinetics of curl-up, sit-up and leg raising/lowering exercises. Seventeen healthy, recreationally trained individuals (13 females and 4 males) volunteered to participate in this study.

Temporal patterns of the trunk muscles remain altered in a low back-injured population despite subjective reports of recovery.

Objective: To compare temporal activation patterns from 24 abdominal and lumbar muscles between healthy subjects and those who reported recovery from recent low back injury (LBI).

Design: Cross-sectional comparative study.

Setting: University neuromuscular function laboratory.

Trunk neuromuscular pattern alterations during a controlled functional task in a low back injured group deemed ready to resume regular activities.

Background: Trunk neuromuscular alterations have been found in those with chronic low back pain, but less well studied are whether responses are altered in those deemed recovered following an injury. Furthermore, coordinated trunk muscle responses are deemed important for normal spinal function, but there are no studies of temporal patterns early after a low back injury. Determining whether altered trunk muscle patterns exist early after injury could improve our understanding of recovery by providing an objective assessment of functional recovery and risk of re-injury.

Active hip and spine ROM differs when comparing unconstrained motion with voluntary segmental constraint.

Background: Active range of motion trials are frequently used as a baseline for normalizing other data. However, previous research has not focused on methods utilized to achieve maximum active range of motion.

Methods: Twenty-seven males (age 20-38 years) participated in this study.

Improvements in hip flexibility do not transfer to mobility in functional movement patterns.

The purpose of this study was to analyze the transference of increased passive hip range of motion (ROM) and core endurance to functional movement. Twenty-four healthy young men with limited hip mobility were randomly assigned to 4 intervention groups: group 1, stretching; group 2, stretching plus hip/spine disassociation exercises; group 3, core endurance; and group 4, control. Previous work has documented the large increase in passive ROM and core endurance that was attained over the 6-week interventions, but whether these changes transferred to functional activities was unclear.

How do elliptical machines differ from walking: a study of torso motion and muscle activity.

Background: The elliptical trainer is a popular exercise modality, yet its effect on the lumbar spine is poorly understood. The purpose of this study was to analyze the effect of different hand positions, speed and stride lengths on spine kinematics and corresponding muscle activity while using the elliptical trainer, and compare with those demonstrated in normal walking.

Methods: Electromyographic data was collected over 16 trunk and gluteal muscle sites on 40 healthy males (mean age (SD)=23(3)) while on the elliptical trainer.

Trunk muscle activation during stabilization exercises with single and double leg support.

The aim of this study was to analyze trunk muscle activity during bridge style stabilization exercises, when combined with single and double leg support strategies. Twenty-nine healthy volunteers performed bridge exercises in 3 different positions (back, front and side bridges), with and without an elevated leg, and a quadruped exercise with contralateral arm and leg raise ("bird-dog"). Surface EMG was bilaterally recorded from rectus abdominis (RA), external and internal oblique (EO, IO), and erector spinae (ES).

Hip joint range of motion improvements using three different interventions.

The purpose of this study was to analyze the effect of 3 different exercise interventions plus a control group on passive hip range of motion (ROM). Previous research studies into the methods of improving passive hip mobility have focused on stretching protocols aimed specifically at the hip joint. The effect of core stabilization, motor training, and myofascial stretching techniques on hip mobility in a selected asymptomatic group with limited hip mobility is unclear.

Abdominal muscle activation changes if the purpose is to control pelvis motion or thorax motion.

The aim of this study was to compare trunk muscular recruitment and lumbar spine kinematics when motion was constrained to either the thorax or the pelvis. Nine healthy women performed four upright standing planar movements (rotations, anterior-posterior translations, medial-lateral translations, and horizontal circles) while constraining pelvis motion and moving the thorax or moving the pelvis while minimizing thorax motion, and four isometric trunk exercises (conventional curl-up, reverse curl-up, cross curl-up, and reverse cross curl-up). Surface EMG (upper and lower rectus abdominis, lateral and medial aspects of external oblique, internal oblique, and latissimus dorsi) and 3D lumbar displacements were recorded.

Quantifying normal 3D hip ROM in healthy young adult males with clinical and laboratory tools: hip mobility restrictions appear to be plane-specific.

Background: Hip mobility is known to affect lumbar spine motion, yet the literature is unclear as to what constitutes normal, limited or excessive motion, given differences in methods, postures, age, etc. The purpose of this study was to establish normative and percentile data for hip rotation and extension, in a young adult male population, using varying methods of quantification.

Methods: 77 males (age 18-35) were recruited.

Trunk muscle activation patterns and spine kinematics when using an oscillating blade: influence of different postures and blade orientations.

Objective: To compare trunk muscle activation patterns and trunk kinematics when using an oscillating blade in standing and unsupported sitting postures, and with different orientations of the blade.

Design: A cross-sectional survey of trunk muscle activities and lumbar motion.

Setting: Biomechanics research laboratory.

MVC techniques to normalize trunk muscle EMG in healthy women.

Normalization of the surface electromyogram (EMG) addresses some of the inherent inter-subject and inter-muscular variability of this signal to enable comparison between muscles and people. The aim of this study was to evaluate the effectiveness of several maximal voluntary isometric contraction (MVC) strategies, and identify maximum electromyographic reference values used for normalizing trunk muscle activity. Eight healthy women performed 11 MVC techniques, including trials in which thorax motion was resisted, trials in which pelvis motion was resisted, shoulder rotation and adduction, and un-resisted MVC maneuvers (maximal abdominal hollowing and maximal abdominal bracing).

Neuromuscular independence of abdominal wall muscles as demonstrated by middle-eastern style dancers.

Previous studies analyzing neuromuscular independence of the abdominal wall have involved a participant population with no specific training in separating individual muscle segments. We chose to study nine women trained in the art of middle-eastern dance, anticipating they may have unique skills in motor control. Specifically, we were searching for evidence of separation of upper rectus abdominis (URA) from lower rectus abdominis (LRA), as well as understanding what role the oblique muscles play in abdominal wall synergies.

Trunk muscle activation patterns, lumbar compressive forces, and spine stability when using the bodyblade.

Background And Purpose: The objective of this study was to analyze the trunk muscle activation patterns, spine kinematics, and lumbar compressive forces that occur when using the Bodyblade, a popular tool in physical medicine clinics.

Subjects: The participants were 14 male subjects who were healthy and who were recruited from a university population.

Methods: With data collected from surface electromyography of selected trunk and shoulder muscles, video analysis, and a 3-dimensional lumbar spine position sensor, modeling methods were used to quantify L4-5 compressive forces and spine stability.