Corticospinal and spinal responses following a single session of lower limb motor skill and resistance training

Prior studies suggest resistance exercise as a potential form of motor learning due to task-specific corticospinal responses observed in single sessions of motor skill and resistance training. While existing literature primarily focuses on upper limb muscles, revealing a task-dependent nature in eliciting corticospinal responses, our aim was to investigate such responses after a single session of lower limb motor skill and resistance training. Twelve participants engaged in a visuomotor force tracking task, self-paced knee extensions, and a control task. Corticospinal, spinal, and neuromuscular responses were measured using transcranial magnetic stimulation (TMS) and peripheral nerve stimulation (PNS). Assessments occurred at baseline, immediately post, and at 30-min intervals over two hours. Force steadiness significantly improved in the visuomotor task (P < 0.001). Significant fixed-effects emerged between conditions for corticospinal excitability, corticospinal inhibition, and spinal excitability (all P < 0.001). Lower limb motor skill training resulted in a greater corticospinal excitability compared to resistance training (mean difference [MD] = 35%, P < 0.001) and control (MD; 37%, P < 0.001). Motor skill training resulted in a lower corticospinal inhibition compared to control (MD; - 10%, P < 0.001) and resistance training (MD; - 9%, P < 0.001). Spinal excitability was lower following motor skill training compared to control (MD; - 28%, P < 0.001). No significant fixed effect of Time or Time*Condition interactions were observed. Our findings highlight task-dependent corticospinal responses in lower limb motor skill training, offering insights for neurorehabilitation program design.

The effect of skilled motor training on corticomotor control of back muscles in different presentations of low back pain

Transcranial magnetic stimulation (TMS) has revealed differences in the motor cortex (M1) between people with and without low back pain (LBP). There is potential to reverse these changes using motor skill training, but it remains unclear whether changes can be induced in people with LBP or whether this differs between LBP presentations. This study (1) compared TMS measures of M1 (single and paired-pulse) and performance of a motor task (lumbopelvic tilting) between individuals with LBP of predominant nociceptive (n = 9) or nociplastic presentation (n = 9) and pain-free individuals (n = 16); (2) compared these measures pre- and post-training; and (3) explored correlations between TMS measures, motor performance, and clinical features. TMS measures did not differ between groups at baseline. The nociplastic group undershot the target in the motor task. Despite improved motor performance for all groups, only MEP amplitudes increased across the recruitment curve and only for the pain-free and nociplastic groups. TMS measures did not correlate with motor performance or clinical features. Some elements of motor task performance and changes in corticomotor excitability differed between LBP groups. Absence of changes in intra-cortical TMS measures suggests regions other than M1 are likely to be involved in skill learning of back muscles.

Corticospinal and spinal adaptations following lower limb motor skill training: a meta-analysis with best evidence synthesis

Motor skill training alters the human nervous system; however, lower limb motor tasks have been less researched compared to upper limb tasks. This meta-analysis with best evidence synthesis aimed to determine the cortical and subcortical responses that occur following lower limb motor skill training, and whether these responses are accompanied by improvements in motor performance. Following a literature search that adhered to the PRISMA guidelines, data were extracted and analysed from six studies (n = 172) for the meta-analysis, and 11 studies (n = 257) were assessed for the best evidence synthesis. Pooled data indicated that lower limb motor skill training increased motor performance, with a standardised mean difference (SMD) of 1.09 being observed. However, lower limb motor skill training had no effect on corticospinal excitability (CSE), Hoffmann's reflex (H-reflex) or muscle compound action potential (M_MAX) amplitude. The best evidence synthesis found strong evidence for improved motor performance and reduced short-interval cortical inhibition (SICI) following lower limb motor skill training, with conflicting evidence towards the modulation of CSE. Taken together, this review highlights the need for further investigation on how motor skill training performed with the lower limb musculature can modulate corticospinal responses. This will also help us to better understand whether these neuronal measures are underpinning mechanisms that support an improvement in motor performance.

Motor skill training versus strength and flexibility exercise in people with chronic low back pain: Preplanned analysis of effects on kinematics during a functional activity

BACKGROUND

People with chronic low back pain display the altered movement pattern where the lumbar spine moves more readily into its available range of motion relative to other joints. A logical approach to treatment, therefore, would be to improve this pattern during functional activities.

METHODS

154 participants were randomized to receive 6 weeks of motor skill training or strength and flexibility exercise. Participants in the motor skill training group received person-specific training to modify their altered movement pattern during functional activities. Participants in the strength and flexibility group received exercises for trunk strength and trunk and lower-limb flexibility. At baseline, post-treatment and 6-months after treatment participants performed a test of picking up an object using their preferred pattern. Three-dimensional marker co-ordinate data were collected. A mixed-model repeated measures analysis of variance was used to examine the treatment group and time effects.

FINDINGS

Motor skill training: Baseline early excursion values [mean (confidence interval)] were as follows: knee = 11.1°(8.0,4.1), hip = 21.2°(19.2,23.1), lumbar = 11.3°(10.4,12.3). From baseline to post-treatment significant improvements in early excursion included: knee = +18.6°(15.4,21.8), hip = +10.8°(8.8,12.8), and lumbar = -2.0°(-0.1,-4.0). There were no significant changes from post-treatment to 6-month follow-up. Strength and flexibility exercise: Baseline early excursion values were as follows: knee = 8.9°(5.8,11.9), hip = 20.8°(18.9,22.8), and lumbar = 11.2°(10.3,12.2) early excursion. There were no significant changes for knee, hip, and lumbar early excursion.

INTERPRETATION

Motor skill training was more effective than strength and flexibility exercise at changing and maintaining change to the altered movement pattern during a functional activity test of picking up an object.

Physical activity, motor performance and skill learning: a focus on primary motor cortex in healthy aging

Participation in physical activity benefits brain health and function. Cognitive function generally demonstrates a noticeable effect of physical activity, but much less is known about areas responsible for controlling movement, such as primary motor cortex (M1). While more physical activity may support M1 plasticity in older adults, the neural mechanisms underlying this beneficial effect remain poorly understood. Aging is inevitably accompanied by diminished motor performance, and the extent of plasticity may also be less in older adults compared with young. Motor complications with aging may, perhaps unsurprisingly, contribute to reduced physical activity in older adults. While the development of non-invasive brain stimulation techniques have identified that human M1 is a crucial site for learning motor skills and recovery of motor function after injury, a considerable lack of knowledge remains about how physical activity impacts M1 with healthy aging. Reducing impaired neural activity in older adults may have important implications after neurological insult, such as stroke, which is more common with advancing age. Therefore, a better understanding about the effects of physical activity on M1 processes and motor learning in older adults may promote healthy aging, but also allow us to facilitate recovery of motor function after neurological injury. This article will initially provide a brief overview of the neurophysiology of M1 in the context of learning motor skills, with a focus on healthy aging in humans. This information will then be proceeded by a more detailed assessment that focuses on whether physical activity benefits motor function and human M1 processes.

Supervised physical therapy vs home exercise program for patients with distal radius fracture: A single-blind randomized clinical study

STUDY DESIGN

Randomized clinical study.

INTRODUCTION

Supervised physical therapy (PT) and home exercise programs (HEPs) are frequently used in the rehabilitation of patients with distal radius fracture (DRF). However, there is no consensus as to whether unsupervised HEP provides comparable benefits to those achieved by supervised PT.

PURPOSE OF THE STUDY

To compare the improvements in pain and functional status between a supervised PT program and unsupervised HEP in DRF patients older than 60 years.

METHODS

A total of 74 patients were randomized into 2 groups. One group received 12 sessions of supervised PT (n = 37), and the other group followed an exercise program at home (n = 37). Three evaluations were performed, before the initiation of treatment, at 6-week, and 6-month follow-up. The study conducted a statistical power analysis to detect an intergroup difference score of 15 points on the Patient-Rated Wrist Evaluation (PRWE). The t-test or Mann-Whitney test was used, and it was set with a significance level of .05.

RESULTS

The supervised PT group showed clinically significant differences in the total PRWE score at 6 weeks (17.67 points, P = .000) in the PRWE function score (15.2 points, P = .000) and in the PRWE pain score (5.6 points, P = .039). There was also a significant difference in the total PRWE score at 6-month follow-up (17.05 points, P = .000) in the PRWE function score (14.5 points, P = .000) and in the PRWE pain score (2.5 points, P = .35).

CONCLUSIONS

A supervised PT program is more effective for improving function in the short- and medium-term when compared with HEP in patients older than 60 years with DRF extraarticular without immediate complications.

LEVEL OF EVIDENCE

1b.

The effect of a motor skills training program in the improvement of practiced and non-practiced tasks performance in children with developmental coordination disorder (DCD)

The purpose of the present study was to examine the effect of a group-based task oriented skills training program on motor and physical ability for children with DCD. It was also investigated if there was an effect on fine motor and handwriting tasks that were not specifically practiced during the training program. Forty-one children aged 6-10years took part in this study. Children were assigned to three groups: an experimental training group consisting of 14 children with DCD, a control non-training group consisted of 13 children with DCD and a control non-training group consisting of 14 typically developed children. The measurements included were, the Movement Assessment Battery for Children (MABC), the Modified Agility Test (MAT), the Triple Hop Distance (THD), the 5 Jump-test (5JT) and the Handwriting Performance Test. All measures were administered pre and post an 8-week training program. The results showed that 10 children of the DCD training-group improved their performance in MABC test, attaining a score above the 15th percentile after their participation in the training program. DCD training-group showed a significant improvement on all cluster scores (manual dexterity (t (13)=5.3, p<.001), ball skills (t (13)=2.73, p<.05) and balance (t (13)=5.13, p<.001). Significant performance improvements were also found in MAT, THD, 5JT (t (13)=-4.55; p<.01), handwriting quality (t (12)=-2.73; p<.05) and speed (t (12)=-4.2; p<.01) after the training program. In conclusion, improvement in both practiced and non-practiced skills, in the training program, may reflect improvement in motor skill but also transfer to other skills.