Walking Slope and Heavy Backpacks Affect Peak and Impulsive Lumbar Joint Contact Forces.

Heavy load carriage is associated with musculoskeletal overuse injury, particularly in the lumbar spine. In addition, steep walking slopes and heavy backpacks separately require adaptation of torso kinematics, but the combined effect of sloped walking and heavy backpack loads on lumbar joint contact forces is unclear. Backpacks with hip belt attachments can reduce pressure under the shoulder straps; however, it is unknown if wearing a hip belt reduces lumbar spine forces.

Effect of Cold vs Temperate Conditions on Physical Performance During Extended Mountain Warfare Training at Moderate Altitude.

Introduction: The purpose of this study was to investigate the effect of environmental conditions on body composition, upper body power, and lower body power throughout a ∼4-week military mountain training exercise. We hypothesized that countermovement jump and ballistic push-up performance would decrease as a result of extended mountain field training and that winter (cold) conditions would result in greater decrements compared to fall (temperate) conditions. We also expected to observe a strong positive correlation between changes in performance and changes in skeletal muscle mass.

The Association Between Grip Strength, Upper Body Power, and Limb Dominance in a Military Population.

Introduction: Military service members rely on upper body strength and power to accomplish tasks such as carrying heavy weapons and gear, rappelling, combat grappling, and marksmanship. Early identification of the factors that lead to reduced upper body strength and power would enable leadership to predict and mitigate aspects that decrease military operational readiness and increase injury risk. The purpose of this study was to investigate the relationship between grip strength and upper body power in U.

Psoas force recruitment in full-body musculoskeletal movement simulations is restored with a geometrically informed cost function weighting.

Simulations of musculoskeletal models are useful for estimating internal muscle and joint forces. However, predicted forces rely on optimization and modeling formulations. Geometric detail is important to predict muscle forces, and greater geometric complexity is required for muscles that have broad attachments or span many joints, as in the torso.

Concentric and eccentric hip musculotendon work depends on backpack loads and walking slopes.

Hip muscle weakness is associated with low back and leg injuries. In addition, hiking with heavy loads is linked to high incidence of overuse injuries. Walking with heavy loads on slopes alters hip biomechanics compared to unloaded walking, but individual muscle mechanical work in these challenging conditions is unknown.

Advancing a U.S. navy shipboard infrastructure for sleep monitoring with wearable technology.

Development of fatigue management solutions is critical to U.S. Navy populations.

Effects of foot intensive rehabilitation (FIRE) on clinical outcomes for patients with chronic ankle instability: a randomized controlled trial protocol.

Background: Lateral ankle sprains account for a large proportion of musculoskeletal injuries among civilians and military service members, with up to 40% of patients developing chronic ankle instability (CAI). Although foot function is compromised in patients with CAI, these impairments are not routinely addressed by current standard of care (SOC) rehabilitation protocols, potentially limiting their effectiveness. The purpose of this randomized controlled trial is to determine if a Foot Intensive REhabilitation (FIRE) protocol is more effective compared to SOC rehabilitation for patients with CAI.

Walking slope and heavy backpack loads affect torso muscle activity and kinematics.

The independent effects of sloped walking or carrying a heavy backpack on posture and torso muscle activations have been reported. While the combined effects of sloped walking and backpack loads are known to be physically demanding, how back and abdominal muscles adapt to walking on slopes with heavy load is unclear. This study quantified three-dimensional pelvis and torso kinematics and muscle activity from longissimus, iliocostalis, rectus abdominis, and external oblique during walking on 0° and ± 10° degree slopes with and without backpack loads using two different backpack configurations (hip-belt assisted and shoulder-borne).

Assessing Injury Susceptibility at Marine Corps Recruit Depot, San Diego, California.

Poh, PYS, Sessoms, PH, Haluch, KS, and Trone, DW. Assessing injury susceptibility at Marine Corps Recruit Depot, San Diego, California. J Strength Cond Res 37(7): 1530-1536, 2023-Marine Corps Recruit Depot (MCRD) recruits undergo demanding training.

Muscle Engagement Monitoring Using Self-Adhesive Elastic Nanocomposite Fabrics.

Insight into, and measurements of, muscle contraction during movement may help improve the assessment of muscle function, quantification of athletic performance, and understanding of muscle behavior, prior to and during rehabilitation following neuromusculoskeletal injury. A self-adhesive, elastic fabric, nanocomposite, skin-strain sensor was developed and validated for human movement monitoring. We hypothesized that skin-strain measurements from these wearables would reveal different degrees of muscle engagement during functional movements.

The Redesign and Validation of Multimodal Motion-Assisted Memory Desensitization and Reconsolidation Hardware and Software: Mixed Methods, Modified Delphi-Based Validation Study.

Background: In recent years, the delivery of evidence-based therapies targeting posttraumatic stress disorder (PTSD) has been the focus of the Departments of Defense in countries such as Canada, the Netherlands, and the United States. More than 66% of military members continue to experience symptoms of PTSD that significantly impact their daily functioning and quality of life after completing evidence-based treatments. Innovative, engaging, and effective treatments for PTSD are needed.

Uneven Treadmill Training for Rehabilitation of Lateral Ankle Sprains and Chronic Ankle Instability: Protocol for a Pragmatic Randomized Controlled Trial.

Background: Lateral ankle sprains (LASs) are common injuries among military service members. Approximately 40% of individuals with an LAS progress to develop chronic ankle instability (CAI), a condition that results in substantial mechanical and neurophysiological impairment and activity limitation. Since proprioceptive and balance training improve functional outcomes and prevent secondary injury following LAS, they are recommended in clinical practice.

Head and Body Dyskinesia During Gait in Tactical Athletes With Vestibular Deficit Following Concussion.

Vestibular deficit is common following concussion and may affect gait. The purpose of this study was to investigate differences in head and pelvic center of mass (COM) movement during gait in military tactical athletes with and without concussion-related central vestibular impairment. 24 patients with post-concussion vestibular impairment (20 males, 4 females; age: 31.

A backpack load sharing model to evaluate lumbar and hip joint contact forces during shoulder borne and hip belt assisted load carriage.

Musculoskeletal injuries of the lumbar spine occur frequently among military service members and are associated with heavy backpack loads. Musculoskeletal modeling and simulation facilitate biomechanical evaluation to compare different backpack designs. We developed a backpack attachment model that can be tuned to represent various load distributions between the torso and pelvis.

Trauma Exposure and Functional Movement Characteristics of Male Tactical Athletes.

Context: Tactical athletes commonly experience high levels of physical stress, which may increase their risk of musculoskeletal injury. It is critical to understand psychological predictors of functional movement (FM), which may help prevent musculoskeletal injury in this population.

Objective: To determine the associations of combat and trauma exposure with FM characteristics of male tactical athletes.

Effect of a load distribution system on mobility and performance during simulated and field hiking while under load.

This study was conducted to test a modular scalable vest-load distribution system (MSV-LDS) against the plate carrier system (PC) currently used by the United States Marine Corps. Ten Marines engaged in 1.6 km load carriage trials in seven experimental conditions in a laboratory study.

Performance of an attention-demanding task during treadmill walking shifts the noise qualities of step-to-step variation in step width.

Background: The fractal scaling evident in the step-to-step fluctuations of stepping-related time series reflects, to some degree, neuromotor noise.

Research Question: The primary purpose of this study was to determine the extent to which the fractal scaling of step width, step width and step width variability are affected by performance of an attention-demanding task. We hypothesized that the attention-demanding task would shift the structure of the step width time series toward white, uncorrelated noise.

Improvements in dizziness and imbalance results from using a multi disciplinary and multi sensory approach to Vestibular Physical Therapy - a case study.

This paper discusses a case study of a 41-year-old active duty male service member who sustained head trauma from a motorcycle accident and underwent multidisciplinary vestibular physical therapy rehabilitation. He was initially treated with traditional physical therapy applications of treadmill walking and standing balance with some symptom improvements, but was not able to maintain a running speed that would allow him to return to full active duty status. Further treatment utilizing a Computer Assisted Rehabilitation Environment was performed in order to increase level of difficulty and further enhance function.

Improvements in gait speed and weight shift of persons with traumatic brain injury and vestibular dysfunction using a virtual reality computer-assisted rehabilitation environment.

Many people sustaining a traumatic brain injury experience vestibular pathology requiring physical therapy for treatment. This study measured improvements in gait speed and weight shift for subjects receiving vestibular physical therapy using a Computer-Assisted Rehabilitation Environment (CAREN). A 6-session CAREN, 6-session traditional vestibular therapy group was compared with a 12-session CAREN only (0 traditional sessions) therapy group.

Head stabilization measurements as a potential evaluation tool for comparison of persons with TBI and vestibular dysfunction with healthy controls.

A large percentage of persons with traumatic brain injury incur some type of vestibular dysfunction requiring vestibular physical therapy. These injuries may affect the natural ability to stabilize the head while walking. A simple method of utilizing motion capture equipment to measure head movement while walking was used to assess improvements in head stabilization of persons undergoing computerized vestibular physical therapy and virtual reality training for treatment of their vestibular problems.

A systematic literature review of the use and effectiveness of the Computer Assisted Rehabilitation Environment for research and rehabilitation as it relates to the wounded warrior.

Background: Several U.S. military treatment and research facilities employ a Computer Assisted Rehabilitation Environment (CAREN) [Motek Medical BV, Amsterdam, The Netherlands] for research and rehabilitation of complex injuries exhibited by Wounded Warriors.

Task-specific fall prevention training is effective for warfighters with transtibial amputations.

Background: Key factors limiting patients with lower extremity amputations to achieve maximal functional capabilities are falls and fear of falling. A task-specific fall prevention training program has successfully reduced prospectively recorded trip-related falls that occur in the community by the elderly. However, this program has not been tested in amputees.

Method for evoking a trip-like response using a treadmill-based perturbation during locomotion.

Because trip-related falls account for a significant proportion of falls by patients with amputations and older adults, the ability to repeatedly and reliably simulate a trip or evoke a trip-like response in a laboratory setting has potential utility as a tool to assess trip-related fall risk and as a training tool to reduce fall risk. This paper describes a treadmill-based method for delivering postural perturbations during locomotion to evoke a trip-like response and serve as a surrogate for an overground trip. Subjects walked at a normalized velocity in a Computer Assisted Rehabilitation Environment (CAREN).