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Background: Transcranial direct current stimulation (tDCS) has been demonstrated to facilitate motor performance in healthy individuals; however, results are variable. The neuromodulatory effects of tDCS during visuomotor tasks may be influenced by extrinsic visual feedback. However, this interaction between tDCS and visual feedback has not been explored for the lower limb. Hence, our objective was to explore if tDCS over the primary lower limb motor cortex differentially facilitates motor performance based on the availability of visual feedback. Methods: Twenty-two neurotypical adults performed ankle plantarflexion and dorsiflexion movements while tracking a sinusoidal target. Spatiotemporal, spatial, and temporal error were calculated between the ankle position and target. Participants attended two sessions, a week apart, with (Stim) and without (No-Stim) anodal tDCS. Sessions were divided into two blocks containing randomized visual feedback conditions: full, no, and blindfold. During Stim sessions, the first block included the application of tDCS to the lower limb M1. Results: Spatiotemporal and spatial error increased as feedback faded (p < .001). A two-way repeated-measures analysis of variance showed a significant interaction between tDCS and visual feedback (p < .05) on spatiotemporal error. Post hoc analyses revealed a significant improvement in spatiotemporal error when visual feedback was absent (p < .01). Spatial and temporal errors were not significantly affected by stimulation or visual feedback. Discussion: Our results suggest that tDCS enhances spatiotemporal ankle motor performance only when visual feedback is not available. These findings indicate that visual feedback may play an important role in demonstrating the effectiveness of tDCS.

The purpose of this study was to assess the efficacy of a combined training program (CTP) in reducing the effects of dual tasking on the temporal parameters and kinematics of gait, as compared with single-task gait. A controlled, randomized, intervention study was performed in an intervention group and a control group. The intervention group attended three weekly CTP sessions for 24 weeks. Gait pattern was evaluated prior to the baseline intervention, at 12 weeks, and at 24 weeks (Repost). The sample was composed of 22 subjects diagnosed with multiple sclerosis with an Expanded Disability Status Scale score of 0–5.5. A total of 12 patients were allocated to the intervention group and another 10 to the control group. A three-dimensional photogrammetry scanner was connected to a selective attention system designed to present a dual-task gait condition. Dual tasking had an impact on all spatiotemporal parameters of gait, and the most remarkable effect of dual tasking was on double-support time, which increased by 9% with respect to normal walking. In contrast, dual tasking had a trivial effect on single-support time. The CTP was effective in reducing the effects of dual tasking on stride length and velocity of the center of mass after Repost of training (p < .05). The CTP reduced time in double-support phase, whereas single-support time increased after Repost of intervention. The application of the CTP had no effect on the cost of the double task after 12 weeks of intervention. It is suggested to increase the application time over Repost.

This narrative review seeks to compare the various ways in which motor creativity has been measured and to critically evaluate those methods within the context of our contemporary understanding of motor creativity. Eligible studies included those of any study design, experimental or observational, as long as motor creativity was measured. Three databases (i.e., PubMed, Scopus, and ScienceDirect) were searched from the earliest possible start dates to December 2021. No risk of bias assessment was performed as the study outcomes were not the focus of the review. After screening for eligibility, 23 articles were included for review, all having measured motor creativity. Of the 23 articles, 16 measured generic motor creativity, while the remaining seven measured task-specific motor creativity. Furthermore, 16 of the studies tested motor creativity with largely static environmental constraints, while the remaining seven were conducted with dynamic environmental constraints. Using a contemporary understanding of motor creativity, most motor creativity tests presently do not possess sufficient task specificity and environmental dynamism, which may not provide an appropriate context for the emergence of creative motor action.

This study aims to analyze the effects of a training program based on practice variability on the speed and accuracy of the tennis forehand approach to the net shot. The study sample consisted of 35 players of both genders, 22 men and 13 women (age 44 ± 10.9 years, height 1.73 ± 0.8 cm, and weight 74.7 ± 8.4 kg). Players were randomly distributed into two groups (control group = 18 and experimental group = 17). Both training groups worked a total volume of 4 weeks, seven sessions, and 15 min per session of forehand approach shot. Control group performed traditional training while experimental group trained with variability using wristband weights. The data obtained showed a large Group × Time interaction in the accuracy of the forehand approach shot, F(1, 16) = 28.034, p < .001, η² = .637. Only the experimental group increased significantly in the accuracy after the program (51.4%, effect size = 1.3, p < .001), while no changes were achieved regarding hitting speed (1.2%, effect size  = 0.12, p = .62). The control group did not improve in any of the tested variables. These results indicate that variability of training using wrist weights is a valid option to improve forehand approach shot accuracy in recreational-level players. Although stroke speed was not increased, this type of training may be interesting as accuracy and technical control is commonly the main goal of training at this level.

This study aimed to explore the effects of mental fatigue (MF) induced by an incongruent Stroop task (ST) and by using social media (SM) compared to watching a documentary (control) on dynamic resistance training. Twenty-one resistance-trained males attended three identical experimental sessions with the only difference of the randomized cognitive task (ST, SM, or control). Each session consisted of (a) baseline MF and motivation visual analogue scale responses, (b) cognitive task, (c) postvisual analogue scale responses, (d) warm-up, and (e) resistance training based on three sets of bench press at 65% of one-repetition maximum till concentric failure. Number of repetitions, ratings of perceived exertion, mean velocity of repetitions, and three repetitions in reserve estimated by subjects were recorded for each set. Both ST (p < .001) and SM (p = .010) effectively induced MF, but only ST impaired the number of repetitions performed in Set 2 (p = .036) and generated higher-than-normal levels of ratings of perceived exertion even reaching significant differences compared to SM in Set 1 (p = .005). However, SM also affected neuromuscular performance by impairing movement velocity in Set 1 (p = .003). The ability of estimating three repetitions in reserve or motivation was not affected by any condition (p range = .362–.979). MF induced by ST impaired the number of repetitions performed, what seems to be mediated by higher-than-normal levels of ratings of perceived exertion. Besides, SM also impaired the ability to apply force against 65% of one-repetition maximum measured by movement velocity.

The aim of this study was to explore the effects of mental fatigue from smartphone use and Stroop task on bench press force–velocity (F-V) profile, one-repetition maximum (1RM), and countermovement jump (CMJ) performance. Twenty-five trained subjects (age = 25.8 ± 5.7 years) completed three sessions separated by 1 week following a randomized double-blinded crossover design. Each session consisted of F-V relationship, 1RM, and CMJ measurements after performing 30 min of control, social media, or Stroop task. Perceived mental fatigue and motivation were recorded. Mental fatigue, motivation, CMJ height, bench press 1RM, and F-V profile variables (maximal force, maximal velocity, and maximal power) were compared between interventions. Significant differences were found for mental fatigue between interventions (p ≤ .001). Both ST (p ≤ .001) and SM (p = .007) induced higher mental fatigue than control. However, no significant differences between interventions were observed for any other variable (p = .056–.723). The magnitude of the differences between interventions ranged from negligible to small (effect sizes ≤ 0.24). These results suggest that although both ST and SM were effective to induce mental fatigue, neither ST nor SM affected CMJ performance, bench press 1RM, or any variable of the F-V profile compared with the control task.

Background: Plantar sensation and ankle proprioception occur in a stage-like variance across the life span. However, changes in adolescents, young adults, middle-aged adults, and older adults remain unclear. The aim of this study was to investigate the differences of plantar sensation and ankle proprioception in adolescents to older adults. Methods: A total of 212 participants were recruited in the study and were divided into four groups, including adolescents (n = 46), young adults (n = 55), middle-aged adults (n = 47), and older adults (n = 54). Plantar tactile sensitivity/tactile acuity/vibration threshold and ankle movement threshold/joint position sense/force sense were assessed in all groups. The Kruskal–Wallis H test was used to analyze the differences in Semmes–Weinstein monofilaments between different age groups in different plantar positions. One-way analysis of variance was used to determine differences in foot vibration threshold, two-point discrimination, and ankle proprioception between different age groups. Results: Significant differences were found in the Semmes–Weinstein monofilament test (p < .001), the two-point discrimination test (p < .05), and the vibration threshold test (p < .05) in the six tested plantar positions among adolescents, young adults, middle-aged adults, and older adults. For ankle proprioception, significant differences were found in movement thresholds in ankle plantar flexion (p = .01), ankle dorsiflexion (p < .001), ankle inversion (p < .001), and ankle eversion (p < .001), as well as relative absolute errors in the ankle force senses of ankle plantar flexion (p = .02) and ankle dorsiflexion (p = .02) across the four age groups. Conclusion: Plantar sensation and ankle proprioception were sensitive in adolescents and young adults than in middle-aged adults and older adults.

The study assessed the manifestation of a regulated locomotion pattern while clearing the first two hurdles during running. In addition, the effect of a hurdles’ learning design, using specific activities and manipulated task constraints, on regulation strategies and kinematic reorganization was examined. Pre- and posttests were conducted. Twenty-four young athletes were randomly assigned into an experimental and a control group, and performed 18 training sessions, consisting of a hurdle-based intervention for experimental participants and a more generalized athletics training for control participants. Different footfall variability curves were recorded, suggesting that young athletes regulated locomotion pattern to clear the hurdles according to their needs. Task-specific training contributed to lower values of variability for the entire approach run and to functional movement reorganization, affording learners to take-off further from the hurdle with a higher horizontal velocity, leading to a more flat hurdle clearance stride and to a significant hurdle running performance improvement.

The upstart is commonly used on bars in artistic gymnastics following a release and regrasp skill, where the gymnast will perform a flighted element before catching the bar. The variability of the flighted element leads to varying initial conditions prior to the upstart. The aim of the study was to understand how technique can be manipulated in order to ensure success at the task despite this variability. More specifically, the study aimed to quantify the ranges of initial angular velocity a gymnast could cope with in an upstart using (a) a fixed timing technique, (b) with one additional parameter to modify timings as a function of initial angular velocity, and (c) a further additional parameter to extend the range. Relationships were established, using computer simulation modeling, between the movement pattern parameters, which defined the technique, and the initial angular velocity of the upstart. A two-parameter relationship outperformed both the one-parameter relationship and the fixed timing solution in terms of the range of initial angular velocities the model could cope with. One of the two parameters governed the time by which the initiation of the shoulder extension should be reduced as a function of increased initial angular velocity, and the other parameter performed the same function for the remaining timing parameters at the hip and shoulder. The present study suggests that gymnasts, and, therefore, humans, may be able to modify movement patterns to cope with uncertain initial conditions using a relatively small number of parameters.