Are practice trials required for hop tests?

Journal of Biomechanics

Dharia

Augenstein

et al. 2019

Self Cite

The use of motor learning strategies may enhance rehabilitation outcomes of individuals with neurological injuries (e.g., stroke or cerebral palsy). A common strategy to facilitate learning of challenging tasks is to use sequential progression-i.e., initially reduce task difficulty and slowly increase task difficulty until the desired difficulty level is reached. However, the evidence related to the use of such sequential progressions to improve learning is mixed for functional skill learning tasks, especially considering situations where practice duration is limited. Here, we studied the benefits of sequential progression using a functional motor learning task that has been previously used in gait rehabilitation. Three groups of participants (N=43) learned a novel motor task during treadmill walking using different learning strategies. Participants in the specific group (n=21) practiced only the criterion task (i.e., matching a target template that was scaled-up by 30%) throughout the training. Participants in the sequential group (n=11) gradually progressed to the criterion task (from 3% to 30% in increments of 3%), whereas participants in the random group (n=11) started at 3% and progressed in random increments (involving both increases and decreases in task difficulty) to the criterion task. At the end of training, kinematic tracking performance on the criterion task was evaluated in all participants both with and without visual feedback. Results indicated that the tracking error was significantly lower in the specific group, and no differences were observed between the sequential and the random progression groups. The findings indicate

Section: Participantsmentioning

confidence: 99%

Learning new gait patterns is enhanced by specificity of training rather than progression of task difficulty

Journal of Biomechanics

Dharia

Augenstein

et al. 2019

Self Cite

“…Seventeen healthy adults (8 males, 9 females; 20.1 ± 2.8 years, 1.7 ± 0.1 meters; 64.7 ± 14.3 kilograms) participated in this study after signing an informed consent document that was approved by the University of Michigan Institutional Review Board. All subjects were right leg dominant based on their preferred leg to kick a ball (Krishnan, 2015;Ranganathan et al, 2016;Washabaugh et al, 2016b). Subjects were included in the study if they did not have a history of significant orthopaedic or neurological conditions, psychiatric illness, or any contraindications to transcranial magnetic stimulation (e.g., recent skull fracture or head injury, metal implants in the head, epilepsy, cardiac pacemakers, pregnant females, recurrent fainting spells or syncope, etc.)…”

Section: Subjectsmentioning

confidence: 99%

Effect of paired-pulse stimulus parameters on the two phases of short interval intracortical inhibition in the quadriceps muscle group

2019

RNN

Self Cite

Background: Short interval intracortical inhibition (SICI) is commonly used to assess inhibition in the motor cortex and is known to be affected by the paired-pulse stimulus parameters (i.e., interstimulus interval [ISI], conditioning stimulus intensity [CSI] and test stimulus intensity [TSI]) used during testing. While the effects of stimulus parameters are well-studied in the upperextremity, evidence in the lower-extremity is lacking.Objective: To comprehensively examine the effects of alterations in paired-pulse stimulus parameters on the two phases of SICI in the quadriceps muscle group.Methods: Seventeen adults (8 males, 9 females) volunteered to participate in this study. SICI was examined over a range of CSIs (70-90% active motor threshold [AMT]), TSIs (100-140% AMT), and ISIs (1.0-3.0 ms) using both EMG and torque responses elicited by transcranial magnetic stimulation (TMS). Results:The results indicated that SICI at 1.0 ms ISI was best revealed with a CSI of 70% and TSI ≥ 110% AMT, whereas SICI at 2.5 ms ISI was best revealed with a CSI of 80-90% and a TSI of ≥ 130% AMT. Unlike upper-extremity muscles, evaluating SICI with a CSI of 70% AMT and an ISI of 1.0 ms produced the greatest inhibition for all TSIs. In general, inhibitory effects were contaminated by facilitatory effects when using a TSI of 100% AMT. Conclusions:The amount of inhibition was dependent on the stimulation parameters used during testing. A CSI of 70% AMT, ISI of 1.0 ms, and TSI of ≥ 110% AMT appear to be optimal for measuring SICI in the quadriceps muscle; however, other parameters can be used if careful consideration is given to the described interaction between the parameters.

Learning and interlimb transfer of new gait patterns are facilitated by distributed practice across days

2019

Gait & Posture

Self Cite

Background: Previous studies have shown that the extent to which learning with one limb transfers to the opposite, untrained limb (i.e., interlimb transfer) is proportional to the amount of prior learning (or skill acquisition) that has occurred in the training limb. Thus, it is likely that distributed practice-a training strategy that is known to facilitate learning-will result in greater interlimb transfer than massed practice. Research Question: To evaluate the effects of massed and distributed practice on acquisition and interlimb transfer of leg motor skills during walking. Methods: Forty-five subjects learned a new gait pattern that required greater hip and knee flexion during the swing phase of gait. The new gait pattern was displayed as a foot trajectory in the sagittal plane and participants attempted to match their foot trajectory to this template. Subjects in the massed practice group (n=20) learned the task on a single day, whereas subjects in the distributed practice group (n=25) learned the task that was spaced over two consecutive days (training phase). Following completion of training, subjects in both groups practiced the task with their untrained, opposite leg to evaluate interlimb transfer (transfer phase). Results: Results indicated that the amount of skill acquisition (i.e., reductions in tracking error) on the training leg was significantly higher (P < 0.05) in the distributed practice group when compared with the massed practice group. Similarly, the amount of interlimb transfer was also significantly higher (P < 0.05) in the distributed practice group both at the beginning and end of the transfer phase.