0000000000999331
AUTHOR
Patrick J. Owen
Identifying and Assessing Inter-Muscular Fat at the Distal Diaphyseal Femur Measured by Peripheral Quantitative Computed Tomography (pQCT)
INTRODUCTION Inter/intramuscular fat can be assessed with peripheral Quantitative Computed Tomography (pQCT) and is of interest as an indicator of ‘muscle quality’. Typical pQCT scan sites (forearm, lower leg) have a low amount of inter/intramuscular fat, however distal diaphyseal femur scan sites with conspicuous inter/intramuscular fat have been identified as potentially more prudent scan sites, even in healthy adolescents. However, current state of the art analysis methods require labour-intensive manual segmentation of the scan. The purpose of the present study was to evaluate the reliability of a novel open source automated enclosing convex polygon approach (source code https://github.…
Does Use of Androgen Deprivation Therapy (ADT) in Men with Prostate Cancer Increase the Risk of Sarcopenia?
Androgen deprivation therapy (ADT) for prostate cancer (PCa) can compromise muscle health. Hence, we aimed to quantify the prevalence of sarcopenia (i.e., compromised lean mass, muscle strength, and physical function) in ADT-treated (> 12 week) men (n = 70) compared to similarly aged non-ADT-treated PCa (n = 52) and healthy controls (n = 70). Lean and fat mass were quantified by dual-energy X-ray absorptiometry. Muscle strength and function were measured using handgrip dynamometry and gait speed, respectively. Sarcopenia was defined as low adjusted appendicular lean mass [ALM; height-adjusted (ALMI), body mass index-adjusted (ALMBMI) and height and fat mass-adjusted (ALMHFM)] with weak hand…
Increased Joint Mobility Is Associated With Impaired Transversus Abdominis Contraction.
Mitchell, UH, Owen, PJ, Rantalainen, T, and Belavý, DL. Increased joint mobility is associated with impaired transversus abdominis contraction. J Strength Cond Res 36(9): 2472-2478, 2022-Increased joint mobility is a risk factor for joint injury, but muscle function may be able to compensate for it. Current evidence suggests reduced force production capacity in people with hypermobility. However, little is known about the lumbar spine. The purpose of this cross-sectional study was to assess whether there was a link between joint mobility and transverse abdominis and multifidus muscles contraction, muscles ascribed a core-stability role. Using a modified quantitative version of the Beighton …
Axial loading and posture cues in contraction of transversus abdominis and multifidus with exercise
AbstractAstronauts are at increased risk of spine injury. With a view to developing training approaches for the muscles of the spine in microgravity, this study examined the effects of axial loading and postural cues on the contraction of transversus abdominis and lumbar multifidus in supine lying using a novel exercise device (GravityFit). Thirty (18 males and 12 females) endurance-trained runners without a history of spinal pain aged 33–55 years were recruited. Magnetic resonance imaging (MRI) was performed under one rest and five exercise conditions, which involved variations in axial loading and postural cues. Whole volume of the abdominal and lumbar paraspinal muscles was imaged and tr…
Characterization of Intervertebral Disc Changes in Asymptomatic Individuals with Distinct Physical Activity Histories Using Three Different Quantitative MRI Techniques
(1) Background: Assessments of intervertebral disc (IVD) changes, and IVD tissue adaptations due to physical activity, for example, remains challenging. Newer magnetic resonance imaging techniques can quantify detailed features of the IVD, where T2-mapping and T2-weighted (T2w) and Dixon imaging are potential candidates. Yet, their relative utility has not been examined. The performances of these techniques were investigated to characterize IVD differences in asymptomatic individuals with distinct physical activity histories. (2) Methods: In total, 101 participants (54 women) aged 25&ndash
Exercise for the intervertebral disc : a 6-month randomised controlled trial in chronic low back pain
Background context Muscle, bone and tendon respond anabolically to mechanical forces. Whether the intervertebral disc (IVD) can benefit from exercise is unclear. Purpose To examine whether exercise can beneficially affect IVD characteristics. Study design/setting This is a single-blinded 6-month randomised controlled trial (ACTRN12615001270505) in an exercise and physiotherapy clinic. Patient sample Forty patients with chronic non-specific low back pain (NSCLBP) are included in this study. Outcome measures The primary outcome was lumbar IVD T2 time (MRI). Secondary outcomes included IVD diffusion coefficient and IVD expansion with short-duration lying. Methods Twenty patients progressively …
Transversus abdominis and multifidus asymmetry in runners measured by MRI: a cross-sectional study
ObjectiveThe transversus abdominis muscle (TrA) is active during running as a secondary respiratory muscle and acts, together with the multifidus, as trunk stabiliser. The purpose of this study was to determine size and symmetry of TrA and multifidus muscles at rest and with contraction in endurance runners without low back pain.DesignCross-sectional study.SettingA medical imaging centre in Melbourne, Australia.ParticipantsThirty middle-aged (43years±7) endurance-trained male (n=18) and female (n=12) runners without current or history of low back pain.Outcome measuresMRI at rest and with the core engaged. The TrA and multifidus muscles were measured for thickness and length (TrA) and antero…
Mechanical loading influences the lumbar intervertebral disc. A cross-sectional study in 308 athletes and 71 controls.
There is evidence in animal populations that loading and exercise can positively impact the intervertebral disc (IVD). However, there is a paucity of information in humans. We examined the lumbar IVDs in 308 young athletes across six sporting groups (baseball, swimming, basketball, kendo, soccer, and running; mean age 19 years) and 71 nonathletic controls. IVD status was quantified via the ratio of IVD to vertebral body height (IVD hypertrophy) and ratio of signal intensity in the nucleus to that in the annulus signal (IVD nucleus hydration) on sagittal T2-weighted magnetic resonance imaging. P values were adjusted via the false discovery rate method to mitigate false positives. In examinin…
Bone mineral density, structure, distribution and strength in men with prostate cancer treated with androgen deprivation therapy
Androgen deprivation therapy (ADT) improves survival in men with advanced prostate cancer (PCa), but has been associated with compromised skeletal health and increased fracture risk. However, limited previous research has investigated determinants of bone strength beyond DXA-derived areal bone mineral density (aBMD) in this population group. The aim of this cross-sectional study was to investigate the effects of ADT in men with PCa on BMD, bone structure, estimates of whole bone strength and cortical bone distribution. A total of 70 ADT-treated men, 52 PCa controls and 70 healthy controls had DXA lumbar spine and proximal femur aBMD and pQCT distal (4%) and proximal (66%) tibia and radius c…
Serratus anterior contraction during resisted arm extension (GravityFit) assessed by MRI
Background: Scapular stabilization is a common focus of shoulder rehabilitation. Objective: Examine contraction of serratus anterior during a bilateral arm extension exercise with axial compression using an exercise device (GravityFit) by magnetic resonance imaging (MRI). Methods: MRI was performed under two conditions: rest and static arm extension with axial compression. Load was set at 20% of age, sex and weight estimated bench press one-repetition maximum. A T2-weighted sequence was used to collect 14 axial images of the upper thoracic spine and shoulder bilaterally. Mean muscle length and thickness were calculated for the whole muscle and in equidistant subregions of the muscle in its …
Musculoskeletal Responses to Exercise Plus Nutrition in Men with Prostate Cancer on Androgen Deprivation: A 12-Month RCT
PURPOSE Androgen deprivation therapy (ADT) for prostate cancer has multiple adverse effects on musculoskeletal health. This 12-month randomized controlled trial aimed to assess the effects of multicomponent exercise training combined with whey protein, calcium and vitamin D supplementation on bone mineral density (BMD), structure and strength, body composition, muscle strength, and physical function in ADT-treated men. METHODS Seventy ADT-treated men were randomized to exercise plus supplementation (Ex + Suppl; n = 34) or usual care (control; n = 36). Ex + Suppl involved thrice weekly progressive resistance training plus weight-bearing impact exercise with daily multinutrient supplementatio…
Randomized Trial of General Strength and Conditioning versus Motor Control and Manual Therapy for Chronic Low Back Pain on Physical and Self-Report Outcomes
Exercise and spinal manipulative therapy are commonly used for the treatment of chronic low back pain (CLBP) in Australia. Reduction in pain intensity is a common outcome
The clinical relevance of adiposity when assessing muscle health in men treated with androgen deprivation for prostate cancer
Background: Androgen deprivation therapy (ADT) for prostate cancer (PCa) may prospectively decrease absolute lean mass (LM) and increase absolute fat mass (FM). Given that estimates of LM by dual‐energy X‐ray absorptiometry may be overestimated in obese people, this study examined the influence of adiposity on muscle health in men treated with ADT for PCa. Methods: This cross‐sectional study examined the influence of adiposity on total and appendicular LM (ALM), muscle cross‐sectional (CSA), and muscle strength in 70 men treated with ADT [mean (standard deviation) age, 71 (6) years] for PCa compared with age‐matched PCa (n = 52) and healthy controls (n = 70). Total body LM, FM and ALM, and …
Increased Joint Mobility Is Associated With Impaired Transversus Abdominis Contraction
Increased joint mobility is a risk factor for joint injury, but muscle function may be able to compensate for it. Current evidence suggests reduced force production capacity in people with hypermobility. However, little is known about the lumbar spine. The purpose of this cross-sectional study was to assess whether there was a link between joint mobility and transverse abdominis and multifidus muscles contraction, muscles ascribed a core-stability role. Using a modified quantitative version of the Beighton scale (BOM score), we measured joint mobility of 30 middle-aged individuals without low back pain. These scores were correlated with magnetic resonance imaging–derived measures of transve…