Dorsiflexion Specific Ankle Robotics to Enhance Motor Learning After Stroke: A Preliminary Report.

Background: Robotics has emerged as a promising avenue for gait retraining of persons with chronic hemiparetic gait and footdrop, yet there is a gap regarding the biomechanical adaptations that occur with locomotor learning. We developed an ankle exoskeleton (AMBLE) enabling dorsiflexion assist-as-needed across gait cycle sub-events to train and study the biomechanics of motor learning stroke. This single-armed, non-controlled study investigates effects of nine hours (9 weeks × 2 sessions/week) locomotor task-specific ankle robotics training on gait biomechanics and functional mobility in persons with chronic hemiparetic gait and foot drop.

Evaluating Test-Retest Reliability of Fatigability in Chronic Stroke.

Objectives: The subjective nature of fatigue may contribute to inconsistencies in prevalence rates for post-stroke fatigue. More objective performance fatigue measures may offer a more reliable construct of fatigue. Our goal was to establish test-retest reliability of fatigability in stroke during 6-minute walk (6MW) testing.

Physical activity and sleep: An updated umbrella review of the 2018 Physical Activity Guidelines Advisory Committee report.

Physical activity (PA) is widely considered to improve sleep, but a comprehensive review of the research on this topic has not been performed. In this umbrella review, conducted initially for the 2018 Physical Activity Guidelines for Americans Advisory Committee and updated to reflect more recent research, we examined whether PA enhances sleep outcomes across the lifespan as well as among individuals with sleep disorders. Systematic reviews and meta-analyses were utilized to assess the evidence.

CD31+ Circulating Angiogenic Cell Number and Subtypes are Reduced in Individuals with Chronic Stroke.

Background And Purpose: Reduced number and function of CD31+ circulating angiogenic cells (CACs) may explain vascular complications associated with the chronic phase stroke. The purpose of this study was to quantify CD31+ CAC paracrine function, total number and number of various subtypes of CD31+ CACs in individuals with chronic stroke compared with controls.

Methods: Peripheral blood mononuclear cells were isolated from chronic stroke participants and controls.

Aerobic Exercise Recommendations to Optimize Best Practices in Care After Stroke: AEROBICS 2019 Update.

Most stroke survivors have very low levels of cardiovascular fitness, which limits mobility and leads to further physical deconditioning, increased sedentary behavior, and heightened risk of recurrent stroke. Although clinical guidelines recommend that aerobic exercise be a part of routine stroke rehabilitation, clinical uptake has been suboptimal. In 2013, an international group of stroke rehabilitation experts developed a user-friendly set of recommendations to guide screening and prescription-the Aerobic Exercise Recommendations to Optimize Best Practices in Care after Stroke (AEROBICS 2013).

Adaptive Physical Activity for Stroke: An Early-Stage Randomized Controlled Trial in the United States.

. As stroke survival improves, there is an increasing need for effective, low-cost programs to reduce deconditioning and improve mobility. .

Brain-derived neurotrophic factor, epigenetics in stroke skeletal muscle, and exercise training.

Objective: (1) To compare paretic (P) vs nonparetic (NP) skeletal muscle brain-derived neurotrophic factor (BDNF) and the effects of resistive training (RT) on systemic and skeletal muscle BDNF mRNA expression in stroke; and (2) to compare the DNA methylation profile for BDNF and BDNFAS (BDNF antisense RNA) between P and NP muscle and the effects of aerobic exercise training (AEX) on DNA methylation in stroke.

Methods: In this longitudinal investigation, participants (50-76 years) with chronic stroke underwent a fasting blood draw, a 12-week (3×/week) RT intervention (n = 16), and repeated bilateral vastus lateralis muscle tissue biopsies (n = 10) with BDNF expression determined by RT-PCR. Five stroke survivors completed 6 months of AEX (3×/week) and had bilateral muscle biopsies.

Physical Activity to Prevent and Treat Hypertension: A Systematic Review.

Purpose: This systematic umbrella review examines and updates the evidence on the relationship between physical activity (PA) and blood pressure (BP) presented in the 2008 Physical Activity Guidelines Advisory Committee Scientific Report.

Methods: We performed a systematic review to identify systematic reviews and meta-analyses involving adults with normal BP, prehypertension, and hypertension published from 2006 to February 2018.

Results: In total, 17 meta-analyses and one systematic review with 594,129 adults ≥18 yr qualified.

Physical Activity in Cancer Prevention and Survival: A Systematic Review.

Purpose: This article reviews and updates the evidence on the associations between physical activity and risk for cancer, and for mortality in persons with cancer, as presented in the 2018 Physical Activity Guidelines Advisory Committee Scientific Report.

Methods: Systematic reviews of meta-analyses, systematic reviews, and pooled analyses were conducted through December 2016. An updated systematic review of such reports plus original research through February 2018 was conducted.

Physical Activity, Cognition, and Brain Outcomes: A Review of the 2018 Physical Activity Guidelines.

Purpose: Physical activity (PA) is known to improve cognitive and brain function, but debate continues regarding the consistency and magnitude of its effects, populations and cognitive domains most affected, and parameters necessary to achieve the greatest improvements (e.g., dose).

The Scientific Foundation for the Physical Activity Guidelines for Americans, 2nd Edition.

Background: The 2018 Physical Activity Guidelines Advisory Committee Scientific Report provides the evidence base for the Physical Activity Guidelines for Americans, 2nd Edition.

Methods: The 2018 Physical Activity Guidelines Advisory Committee addressed 38 questions and 104 subquestions selected for their public health relevance, potential to inform public policies and programs, maturity of the relevant science, and applicability to the general US population. Rigorous systematic literature searches and literature reviews were performed using standardized methods.

Strength Training for Skeletal Muscle Endurance after Stroke.

Background And Purpose: Initial studies support the use of strength training (ST) as a safe and effective intervention after stroke. Our previous work shows that relatively aggressive, higher intensity ST translates into large effect sizes for paretic and non-paretic leg muscle volume, myostatin expression, and maximum strength post-stroke. An unanswered question pertains to how our unique ST model for stroke impacts skeletal muscle endurance (SME).

Task-specific ankle robotics gait training after stroke: a randomized pilot study.

Background: An unsettled question in the use of robotics for post-stroke gait rehabilitation is whether task-specific locomotor training is more effective than targeting individual joint impairments to improve walking function. The paretic ankle is implicated in gait instability and fall risk, but is difficult to therapeutically isolate and refractory to recovery. We hypothesize that in chronic stroke, treadmill-integrated ankle robotics training is more effective to improve gait function than robotics focused on paretic ankle impairments.

An Engineering Model of Human Balance Control-Part I: Biomechanical Model.

We developed a balance measurement tool (the balanced reach test (BRT)) to assess standing balance while reaching and pointing to a target moving in three-dimensional space according to a sum-of-sines function. We also developed a three-dimensional, 13-segment biomechanical model to analyze performance in this task. Using kinematic and ground reaction force (GRF) data from the BRT, we performed an inverse dynamics analysis to compute the forces and torques applied at each of the joints during the course of a 90 s test.

Higher Treadmill Training Intensity to Address Functional Aerobic Impairment after Stroke.

Background: Peak aerobic capacity (VO2 peak) is severely worsened after disabling stroke, having serious implications for function, metabolism, and ongoing cardiovascular risk. Work from our laboratory and others has previously shown that modest improvements in VO2 peak are possible in stroke participants with aerobic exercise training. The purpose of the current investigation was to test the extent to which greater enhancements in VO2 peak after stroke are possible using a treadmill protocol with far greater emphasis on intensity progression compared with a protocol without such emphasis.

Impact of serum nutritional status on physical function in african american and caucasian stroke survivors.

Background. The purpose of this study is to compare serum nutritional profiles in chronic stroke survivors to a representative sample of US Adults (NHANESIII) and determine whether these serum markers differed by race and impact physical function in stroke. Methods.

Robotically assisted treadmill exercise training for improving peak fitness in chronic motor incomplete spinal cord injury: A randomized controlled trial.

Objective: To assess the effectiveness of robotically assisted body weight supported treadmill training (RABWSTT) for improving cardiovascular fitness in chronic motor incomplete spinal cord injury (CMISCI).

Design: Pilot prospective randomized, controlled clinical trial.

Setting: Outpatient rehabilitation specialty hospital.

Increased reward in ankle robotics training enhances motor control and cortical efficiency in stroke.

Robotics is rapidly emerging as a viable approach to enhance motor recovery after disabling stroke. Current principles of cognitive motor learning recognize a positive relationship between reward and motor learning. Yet no prior studies have established explicitly whether reward improves the rate or efficacy of robotics-assisted rehabilitation or produces neurophysiologic adaptations associated with motor learning.

Physical activity and exercise recommendations for stroke survivors: a statement for healthcare professionals from the American Heart Association/American Stroke Association.

Purpose: This scientific statement provides an overview of the evidence on physical activity and exercise recommendations for stroke survivors. Evidence suggests that stroke survivors experience physical deconditioning and lead sedentary lifestyles. Therefore, this updated scientific statement serves as an overall guide for practitioners to gain a better understanding of the benefits of physical activity and recommendations for prescribing exercise for stroke survivors across all stages of recovery.

Modular ankle robotics training in early subacute stroke: a randomized controlled pilot study.

Unlabelled: BACKGROUND. Modular lower extremity robotics may offer a valuable avenue for restoring neuromotor control after hemiparetic stroke. Prior studies show that visually guided and visually evoked practice with an ankle robot (anklebot) improves paretic ankle motor control that translates into improved overground walking.

Executive function and coping in stroke survivors.

Background: Stroke is a leading cause of disability and sequelae may include physical, emotional, and cognitive impairments. The methods employed to cope with distress, both emotional and cognitive, have not been evaluated in individuals post-stroke. However, research in traumatic brain injury (TBI) suggests that executive function is positively correlated with adaptive coping and negatively correlated with maladaptive coping strategies (Krpan et al.

Clinical application of a modular ankle robot for stroke rehabilitation.

Background: Advances in our understanding of neuroplasticity and motor learning post-stroke are now being leveraged with the use of robotics technology to enhance physical rehabilitation strategies. Major advances have been made with upper extremity robotics, which have been tested for efficacy in multi-site trials across the subacute and chronic phases of stroke. In contrast, use of lower extremity robotics to promote locomotor re-learning has been more recent and presents unique challenges by virtue of the complex multi-segmental mechanics of gait.

Changes in passive ankle stiffness and its effects on gait function in people with chronic stroke.

Mechanical impedance of the ankle is known to influence key aspects of ankle function. We investigated the effects of robot-assisted ankle training in people with chronic stroke on the paretic ankle's passive stiffness and its relationship to overground gait function. Over 6 wk, eight participants with residual hemiparetic deficits engaged in a visuomotor task while seated that required dorsiflexion (DF) or plantar flexion (PF) of their paretic ankle with an ankle robot ("anklebot") assisting as needed.

Test-retest reliability of portable metabolic monitoring after disabling stroke.

Purpose: Impaired economy of gait, prevalent in chronic stroke secondary to residual gait deficits, is associated with intolerance for performing activities of daily living. Gait economy/efficiency is traditionally assessed by determining the rate of oxygen consumption during submaximal treadmill walking. However, the mechanics and energetics of treadmill versus overground walking are very different in stroke survivors with ambulatory deficits.