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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.

Introduction: Proprioception is significantly affected by dysfunction of the basal ganglia, which play an important role in sensorimotor integration. Parkinson’s disease (PD), which is characterized by progressive loss of the dopaminergic neurons of the substantia nigra, leads to a variety of motor and nonmotor symptoms throughout the course of the disease. The aim of this study was to determine trunk position sense and to investigate its relationship with spinal posture and spinal mobility in patients with PD. Methods: The study included 35 patients with PD and 35 age-matched control subjects. Trunk position sense was determined with “trunk reposition errors.” A spinal mouse was used to assess spinal posture and spinal mobility. Results: According to the Hoehn–Yahr rating scale, the majority of the patients were in Stage 1 (68.6%). Trunk position sense was found to be significantly decreased in patients with PD compared with the control group (p < .001) but was not correlated with spinal posture and spinal mobility in patients with PD (p > .05). Conclusions: This study revealed that trunk position sense was impaired in PD from the early stages of the disease. However, neither spinal posture nor spinal mobility was associated with decreased trunk proprioception. Further research into these relationships in the late stages of PD is needed.

Several computational models make predictions about the activation states of individual elements of an action sequence during planning and execution; however, the neural mechanisms of action planning are still poorly understood. Simple chaining models predict that only the first response in an action sequence should be active during planning. Conversely, some parallel activation models suggest that during planning, a serial inhibition process places the individual elements of the action into a serial order across a winner-takes-all competitive choice gradient in which earlier responses are more active, and hence likely to be selected for execution compared with later responses. We triggered transcranial magnetic stimulation pulses at 200 or 400 ms after the onset of a five-letter word, in which all but one response was planned and typed with the left hand, except for a single letter which required a right index finger response exclusively at one of five serial positions. We measured the resulting motor-evoked potentials at the right index finger as a marker for the activation state of that planned response. We observed no difference in motor-evoked potential amplitude across any serial position when a right index finger response was planned at 200 ms after the onset of the word; however, we observed a graded pattern of activation at 400 ms, with earlier positions that required a right index finger response showing greater motor-evoked potentials amplitude compared with later positions. These findings provide empirical support for competitive queuing computational models of action planning.

Previous studies have demonstrated that both visual and proprioceptive feedback play vital roles in mental practice of movements. Tactile sensation has been shown to improve with peripheral sensory stimulation via imperceptible vibratory noise by stimulating the sensorimotor cortex. With both proprioception and tactile sensation sharing the same population of posterior parietal neurons encoding within high-level spatial representations, the effect of imperceptible vibratory noise on motor imagery-based brain–computer interface is unknown. The objective of this study was to investigate the effects of this sensory stimulation via imperceptible vibratory noise applied to the index fingertip in improving motor imagery–based brain–computer interface performance. Fifteen healthy adults (nine males and six females) were studied. Each subject performed three motor imagery tasks, namely drinking, grabbing, and flexion–extension of the wrist, with and without sensory stimulation while being presented a rich immersive visual scenario through a virtual reality headset. Results showed that vibratory noise increased event-related desynchronization during motor imagery compared with no vibration. Furthermore, the task classification percentage was higher with vibration when the tasks were discriminated using a machine learning algorithm. In conclusion, subthreshold random frequency vibration affected motor imagery–related event-related desynchronization and improved task classification performance.

This study aimed to assess, for the first time, how self-reported sleep, mental toughness, and reaction time are impacted by a professional padel tournament. In addition, we evaluated whether sex, age, and/or ranking play a role in this possible effect of a tournament on these variables. Twenty-three professional players (15 men, M _age = 24 ± 6 years; eight women, M _age = 21 ± 5 years) were evaluated on two occasions: (a) baseline, in a noncompetitive week and (b) postmeasure, the morning after an individual was eliminated from the tournament. The Pittsburgh Sleep Quality Index, the Mental Toughness Questionnaire, and the psychomotor vigilance task were used to evaluate the dependent variables. Wilcoxon tests or paired samples t tests were employed to assess the effect of participating in the tournament. To test correlations between variables, Pearson correlation coefficients (quantitative variables) or chi-square distributions (qualitative variables) were employed. Results showed that self-reported sleep (p < .01), mental toughness (p = .01), and reaction time (p = .04) were significantly impaired by the tournament. Exploring moderating variables, results showed that mental toughness did not correlate with sleep impairments (p > .05). In contrast, a nearly significant correlation between sleep impairments and higher reaction times was found (p = .066). No significant effects of age, sex, and ranking were observed. In conclusion, participating in a padel competition impairs the self-reported sleep, mental toughness, and reaction time of professional padel players. A trend toward a significant correlation between the competition-related impairment in sleep and reaction time was observed, whereas age, ranking, and sex were not found to be moderators of any of these impairments.

This study examined whether table tennis as a method of sensorimotor training improves haptic and motor function and to what extent haptic function gain correlates with changes in motor ability in children with probable developmental coordination disorder (pDCD). Children with pDCD were randomly assigned to the table tennis and nontraining control groups. The children in the table tennis group received 36 sessions of table tennis training, including ball balancing, hitting the ball against the wall, strokes, and serving. Haptic sensitivity, acuity, and motor function domains were measured. The results showed a 41.5% improvement in haptic sensitivity in children exposed to table tennis training compared with 2.8% in those without training. This improved haptic sensitivity significantly correlated with motor function gain, suggesting that somatosensory gains occur simultaneously with changes in motor function in children with pDCD. This novel upper limb motor training approach may be an interesting method of sensorimotor training in neurological rehabilitation in children with pDCD.