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Technological tools, like electroencephalography and functional near-infrared spectroscopy, have deepened our understanding of cortical regions involved in balance control. In this systematic literature review, we aimed to identify the prevalent cortical areas activated during balance tasks with specific motor or cognitive demands. Our search strategy encompassed terms related to balance control and cortical activity, yielding 2250 results across five databases. After screening, 67 relevant articles were included in the review. Results indicated that manipulations of visual and/or somatosensory information led to prevalent activity in the parietal, frontal and temporal regions; manipulations of the support base led to prevalent activity of the parietal and frontal regions; both balance-cognitive dual-tasking and reactive responses to extrinsic perturbations led to prevalent activity in the frontal and central regions. These findings deepen our comprehension of the cortical regions activated to manage the complex demands of maintaining body balance in the performance of tasks posing specific requirements. By understanding these cortical activation patterns, researchers and clinicians can develop targeted interventions for balance-related disorders., (© 2024 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

The traditional classifications of motor skills nature (open vs closed; fine vs gross) have not been considered in handedness investigations. Instead, previous research focused on comparing complex vs less complex motor behaviour, leaving a gap in the literature. We compared manual preference between different motor skill characteristics, namely: fine and closed (FC), gross and closed (GC) and gross and open (GO) tasks. The hand preference was assessed with the Global Lateral Preference Inventory in four hundred and forty participants (244 women) aged from 18 to 59 years old. By assessing the degree and direction of handedness in different motor skills, our results showed a stronger lateralization pattern for FC motor skills as compared to GC and GO, with GO also being less lateralized than GC. Our results expand those of previous investigations that used the motor skill complexity definitions by showing how handedness can also be modulated by the interaction between classic motor skills classifications. Future research should consider fine vs. gross and open vs. closed classifications when selecting tasks for analysis of asymmetries of preference.

There are a variety of inventories available to evaluate human lateral preference, but no previous review has systematically analyzed and compared them. We conducted a systematic literature review to identify these inventories and describe their characteristics (e.g., dimensions, scales, tasks, psychometric properties). We included 26 articles, each presenting a different inventory to assess lateral preference, published between 1900 and 2022, selected from the following databases: PubMed, SportDiscus, APA PsycNET, and Web of Science. These inventories analyzed tasks performed in everyday life (domestic, work-related, sports, and leisure/recreation activities), covering hand, foot, hearing, visual and other non-usual lateral preference dimensions, such as trunk and head. Most inventories classified individuals based on the direction (left, indifferent or right preference) and degree (consistent or moderate) of laterality. However, many of the reviewed inventories lack established psychometric verification in their original publication, such as validity, reliability, responsiveness, and practical applicability. Inventories also presented tasks that may be specific to a given cultural setting, limiting their application across different countries. Based on these findings, we provide a comprehensive guide for researchers to select a lateral preference assessment tool, but also advocate for a new inventory with a broader approach, containing more than one dimension of lateral preference (i.e., not only handedness) and tasks that are common to different cultures to enhance practical applicability worldwide., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Between-arm performance asymmetry can be seen in different arm movements requiring specific interjoint coordination to generate the desired hand trajectory. In the current investigation, we assessed between-arm asymmetry of shoulder-elbow coordination and its stability in the performance of circular movements. Participants were 16 healthy right-handed university students. The task consisted of performing cyclic circular movements with either the dominant right arm or the nondominant left arm at movement frequencies ranging from 40% of maximum to maximum frequency in steps of 15%. Kinematic analysis of shoulder and elbow motions was performed through an optoelectronic system in the three-dimensional space. Results showed that as movement frequency increased circularity of left arm movements diminished, taking an elliptical shape, becoming significantly different from the right arm at higher movement frequencies. Shoulder-elbow coordination was found to be asymmetric between the two arms across movement frequencies, with lower shoulder-elbow angle coefficients and higher relative phase for the left compared to the right arm. Results also revealed greater variability of left arm movements in all variables assessed, an outcome observed from low to high movement frequencies. From these findings, we propose that specialization of the left cerebral hemisphere for motor control resides in its higher capacity to generate appropriate and stable interjoint coordination leading to the planned hand trajectory., Competing Interests: Declaration of Competing Interest The authors declare to have neither financial nor non-financial interests that are directly or indirectly related to this work., (Copyright © 2023 Elsevier B.V. All rights reserved.)

TDCS is one of the most commonly used methods among studies with transcranial electrical stimulation and motor skills learning. Differences between study results suggest that the effect of tDCS on motor learning is dependent on the motor task performed or on the tDCS assembly specification used in the learning process. This systematic review aimed to analyze the tDCS effect on motor learning and verify whether this effect is dependent on the task or tDCS assembly specifications. Searches were performed in PubMed, SciELO, LILACS, Web of Science, CINAHL, Scopus, SPORTDiscus, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and PsycINFO. Articles were included that analyzed the effect of tDCS on motor learning through pre-practice, post-practice, retention, and/or transfer tests (period ≥24 h). The tDCS was most frequently applied to the primary motor cortex (M1) or the cerebellar cortex (CC) and the majority of studies found significant stimulation effects. Studies that analyzed identical or similar motor tasks show divergent results for the tDCS effect, even when the assembly specifications are the same. The tDCS effect is not dependent on motor task characteristics or tDCS assembly specifications alone but is dependent on the interaction between these factors. This interaction occurs between uni and bimanual tasks with anodal uni and bihemispheric (bilateral) stimulations at M1 or with anodal unihemispheric stimulations (unilateral and centrally) at CC, and between tasks of greater or lesser difficulty with single or multiple tDCS sessions. Movement time seems to be more sensitive than errors to indicate the effects of tDCS on motor learning, and a sufficient amount of motor practice to reach the "learning plateau" also seems to determine the effect of tDCS on motor learning., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This research investigated the developmental process of five lateral preference dimensions (hand, foot, trunk, hearing, and visual preference). A total of 1236 volunteers participated in this study, divided into five age groups: 07-12 (n = 247); 13-17 (n = 234); 18-30 (n = 227); 31-60 (n = 225); and 61-90 years old (n = 303). Lateral preference was assessed via questionnaire with the Global Lateral Preference Inventory. By assessing the degree and direction of lateral preference in different ages, our results revealed a pattern of lateralization strengthening with aging in all the analyzed dimensions. We also verified significant correlation between hand preference and the other dimensions for all age groups, but correlation was stronger in the 7-12 group for all correlation pairs. Our results lead to the suggestion of an underlying general lateralization process in early ages (7-12 years old) followed by specific developmental trajectories of each preference dimension (13 years forward), likely startled by hemisphere and functional specialization related to innate developmental patterns of neural structures and social/environmental influences., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Transcultural approaches comparing the distribution of lateral preference between countries focused primarily on handedness. However, other laterality dimensions may also be susceptible to cultural variations. The present study compared lateral preference in five dimensions (hand, foot, trunk, hearing, and visual) of young adults from Brazil and Mozambique. Two hundred and two undergraduate students participated in the study, of which 101 were Brazilian (21.7 ± 1.66 years old) and 101 Mozambican (25.6 ± 6.2 years old). The participants' lateral preference direction and degree were assessed using the global lateral preference inventory. Most Brazilians were classified in the moderate preference category, while Mozambicans had a higher frequency of individuals with strong preferences. Hence, Mozambicans presented a higher lateralization degree for all dimensions. A subsequent analysis considering only preference direction (right, left or indifferent), and not degree, did not show the same outcomes, revealing similarities in preference distribution between the two groups. This finding highlights the necessity to incorporate preference degrees in future analysis to not overlook potential differences. We also conclude lateral preference investigations with transcultural approaches should analyse beyond handedness, as other dimensions can also be modulated by cultural characteristics., (© 2022 International Union of Psychological Science.)

Abstract: Nunes, JP, Marcori, AJ, Ribeiro, AS, Cunha, PM, Kassiano, W, Costa, BDV, Aguiar, AF, Nakamura, M, Mayhew, JL, and Cyrino, ES. Differential responsiveness for strength gain between limbs after resistance training in older women: Impact on interlimb asymmetry reduction. J Strength Cond Res 36(11): 3209-3216, 2022-The present study compared strength responses between preferred (PREF) and nonpreferred (N-PREF) legs in older women. Muscular strength was measured unilaterally using an isokinetic dynamometer and was analyzed for reproducibility scores, acute performance, and responsiveness to a resistance training (RT) program. One hundred eleven women (aged ≥60 years) performed 12 weeks of whole-body RT (3 times a week; 4 lower-body exercises). Reproducibility scores (intraclass correlation coefficient ≥0.920; following test-retests in part of the sample at pretraining; n = 19), average acute performances, and average strength gains (PREF = ∼6.9%; N-PREF = ∼7.2%) were similar between legs (p > 0.05). However, the individual analyses showed that some subjects were considered responders to strength gains in 1 leg, whereas nonresponders in the other. Nonetheless, when considering the responses in all strength tests, most subjects (91%) were considered responder to at least 1 measure. In addition, it was observed that the strength ratio between PREF/N-PREF legs was altered for those who presented some asymmetry at baseline, as the limbs became more symmetrical in all strength measures after the RT. In conclusion, we observed that some older women may have different levels of strength between legs; however, a traditional 12-week RT program with bilateral exercises can reduce such asymmetry by inducing greater strength gains in the weaker leg., (Copyright © 2022 National Strength and Conditioning Association.)

Background: People with cerebral palsy (CP) often have difficulties related to maintaining body balance in their daily living activities. Accelerometers are low-cost wearable devices with potential use to objectively assess balance., Research Question: What are the main characteristics and findings from protocols used in research aiming to investigate standing or dynamic body balance stability through trunk accelerometry in people with CP?, Method: We searched in December 2021 seven databases, Pubmed, Embase, Cochrane, Science Direct, Scopus, PEDro, and Lilacs, with descriptors related to cerebral palsy, accelerometer, and balance., Results: Ten studies were included, with a total of 197 evaluated people with CP. These studies were classified as moderate or high methodological quality. We found convergence on the use of the sensor at the lumbar region (L3), with sampling frequency at 100 Hz. For balance assessment, 60 % of the reviewed studies used the 10-m walk test, while the other studies used different walking distances, or the quiet standing test. For data processing, the low-pass filter at 20 Hz has been used predominantly, and the most commonly used variable to evaluate balance stability has been root mean square of trunk acceleration. Children and adolescents with CP had higher acceleration values and greater gait complexity than typically developing children. Individuals with bilateral impairment had greater anteroposterior and mediolateral trunk accelerations than those with unilateral impairment. Trunk acceleration was shown to be sensitive to improvement in gait stability from interventions, and acceleration-based measures have been found to correlate with qualitative balance assessment tools., Significance: Trunk accelerometry in quiet posture and dynamic tasks was shown to be a valid and sensitive measurement to evaluate balance stability in children and adolescents with CP. It is a small, light, low-cost and easy-to-handle tool that is effective for measuring body balance on different tasks in this population., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Single leg balance training promotes significant increments in balance control, but previous reviews on balance control have not analyzed this form of balance training. Accordingly, we aimed to review the single leg balance training literature to better understand the effects of applying this training to healthy individuals. We searched five databases-PubMed, EMBASE, Scopus, Lilacs, and Scielo-with the following inclusion criteria: (a) peer-reviewed articles published in English; (b) analysis of adult participants who had no musculoskeletal injuries or diseases that might impair balance control; and (c) use of methods containing at least a pre-test, exclusive single leg balance training, and a post-test assessment. We included 13 articles meeting these criteria and found that single leg balance training protocols were effective in inducing balance control gains in either single- or multiple-session training and with or without progression of difficulty. Balance control gains were achieved with different amounts of training, ranging from a single short session of 10 minutes to multiple sessions totaling as much as 390 min of unipedal balance time. Generalization of balance gains to untrained tasks and cross-education between legs from single leg balance training were consistent across studies. We concluded that single leg balance training can be used in various contexts to improve balance performance in healthy individuals. These results extend knowledge of expected outcomes from this form of training and aid single leg balance exercise prescription regarding volume, frequency, and potential progressions.

In elite-level soccer, the ability to take shots with both limbs from different positions in the pitch may be key to success. This research aimed to: 1) analyze footedness of elite-football players in European leagues during shooting by computing frequency of right- and left-foot use and accuracy; and 2) investigate whether an athlete's distance from the target (goal, penalty, and outside penalty area) and pitch zone (center, left, or right from the goal) can constrain foot selection during shooting. We analyzed 1826 games from the 2017/18 season, divided between: Spanish LaLiga (380 matches); Italian Serie A (380 matches); English Premier League (380 matches); German Bundesliga (306 matches); and French Ligue 1 (380 matches). Results revealed asymmetrical proportions of foot selection, favoring the preferred foot for right- and left-footed athletes. Frequency of preferred foot selection increased as a function of distance from the target (i.e., the farther the athlete, higher the percentage of preferred foot selection). Shots taken from the left side were more often performed with the right foot and vice-versa, for both left- and right-footed athletes. Interestingly, asymmetries were observed only in foot selection, but not in performance, as success rate did not vary between limbs in any position.

According to the dynamic dominance model, the left cerebral hemisphere is specialized for the control of intersegmental dynamics and the right hemisphere for impedance control. Our aim was to test predictions from the dynamic dominance model in children by comparing performance between the right (preferred) and left hands in aiming. Three groups were compared: 4-7, 8-11, and 18-38 years old. Results showed higher movement linearity in the performance with the right hand in all age groups ( P < .01), while initial directional error and endpoint accuracy were equivalent between hands. These results provided partial support for the dynamic dominance model.

Interlateral transfer of learning between the legs in body balance training is a topic of theoretical and practical interest, but it has been left untouched in previous research. In this investigation, we aimed to evaluate the magnitude and asymmetry of interlateral transfer of balance stability following the practice of a challenging task of unipedal support on an unstable base. Thirty participants (18-30 years old) were assigned to two groups practicing either with the right or the left leg. Training consisted of a single practice session of unipedal balance on a platform free to sway in the anteroposterior direction. Balance time (off ground) of either leg in 10-s trials was compared across pre-test, post-test, and 7-day retention. Post-test indicated that both groups had similar performance gains with the trained leg, and equivalent transfer to the transfer leg. Analysis of retention indicated further balance improvement with both transfer legs, while practice with the right leg led to the superior transfer to the untrained leg as compared to the opposite transfer direction. These results suggest that persistent transfer of learning effects for unipedal dynamic balance is bilateral but more prominent in the right-to-left direction.

Investigation of manual actions has supported the proposition that the right and left cerebral hemispheres have complementary specializations relevant for movement control. To test the extent to which hemisphere specialization affect lower limb control, we compared performance between the legs in two motor tasks. A pedal aiming task was employed to test the notion of left hemisphere specialization for dynamic control, and unipedal balance was employed to test the notion of right hemisphere specialization for impedance control. Evaluation was conducted on young adults, in the contexts of separate (Experiment 1) and integrated (Experiment 2) performance of the probing tasks. Results from the aiming task showed equivalent movement linearity toward the target between the right and left feet across experiments. Analysis of unipedal balance revealed that increased stance stability when supported on the left leg was observed when performing simultaneously the aiming task with the contralateral foot, but not in the context of isolated task performance. These results are inconsistent with the proposition of left hemisphere specialization for dynamic control in the lower limbs, and suggest that specialization of the right hemisphere for impedance control can be observed in balance control when stance is associated with voluntary movements of the contralateral lower limb., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Handedness ontogenesis is still under debate in science. This systematic review analyzed articles regarding the theories and basis of handedness formation, highlighting the historical knowledge path that this literature underwent. Cochrane Library, LILACS, Web of Sciences, Science Direct and PubMed databases were searched. This review included review studies with handedness as the main topic. Only papers written in English with analyses exclusively in neurotypical humans (any age range) were included. Different approaches (genetic, neural, social, and behavioural) were reviewed in light of growing evidence, summarizing the current state of the art. Genetic and environmental/social impacts are common points in most of the reviews, each given more or less importance, depending on the author and theory proposed. Multifactorial, developmental approaches to handedness formation seem to be the most up to date view of the phenomenon. Different control mechanisms between hemisphere and neural asymmetries are also contributing factors to handedness formation.

Handedness is a dynamic and complex aspect of human behavior. Changing it through practice, either willingly or obliged by some reason, requires a considerable amount of effort. Analyzing studies that presented handedness shifts may expand our comprehension of this phenomenon, since knowing how to change it might provide insights into how it develops. Therefore, we reviewed the outcomes of handedness shifts. The results suggest that neural asymmetries related to handedness are likely a consequence of lateralized practice since they correlate with modifications in the behavioral patterns. Clearly, practice is not the only factor influencing handedness development, but it seems to play a significant role in the formation and consolidation of neural and behavioral asymmetries. Another key finding of our review is the suggestion of a ceiling effect for the capacity to change handedness direction and degree, considering none of the reviewed studies reported complete shifts in behavioral measures and brain activation patterns., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The aim of this study was to compare the acute effects of four resistance-training (RT) exercise orders on rate of perceived exertion (RPE) and RT variables with exercise load properly adjusted according to its position within the sequence in older women. That is, the load was adjusted so that it was possible that the sets were performed within the repetition-zone established. Fifteen trained older women (67.4 ± 5.3 years) participated in a crossover-design, combining single-joint (SJ) and multi-joint (MJ) exercises for upper-(UB) and lower-body (LB) in the following exercise orders: SEQA = UBMJ-UBSJ-LBMJ-LBMJ; SEQB = UBSJ-UBMJ-LBSJ-LBMJ; SEQC = LBMJ-LBSJ-UBMJ-UBSJ; SEQD = LBSJ-LBMJ-UBSJ-UBMJ. Each session was comprised of eight exercises with 3 sets of 8-12 repetitions. RPE was analyzed by a sequence (4) × sets (3) two-way ANOVA. Repetitions, time under tension, load, volume-load, and the average RPE of the session were analyzed by one-way ANOVA comparing the four sequences. No significant difference was identified between conditions for total repetitions, time under tension, training load, and volume-load. Lower average RPE of the session was obtained when LB exercises were performed earlier (SEQA: 7.2 ± 1.2, SEQB: 7.1 ± 1.0, SEQC: 6.7 ± 0.9, SEQD: 6.3 ± 1.1). We conclude that when lower body exercises are performed first in a training session, a lower RPE is noted throughout all the session.

There is a considerable amount of evidence sustaining that aerobic exercise causes positive modifications in gray matter density (GMD), especially in the hippocampus and anterior cingulate cortex. However, recent experimental researches with motor learning paradigms are consistently showing that increasing cardiorespiratory capacity is not the only mechanism able to promote positive outcomes in GMD with exercise. In the present study, we present a theoretical suggestion that expanding one's motor repertoire is another primary mechanism related to the increases in GMD. Motor repertoire can be understood as the number of movement possibilities and motor skills that can be performed by a person. Supporting our suggestion, professional athletes present higher GMD than controls, and experimental protocols repeatedly observes positive changes in GMD following motor learning. The relationship between physical inactivity, amputation, and lower GMD values also gives further support for the hypothesis. Follow-up studies monitoring GMD before and after training programs that stimulate new motor skill learning are essential to confirm this proposition. The brain regions related to sensory processing of the motor tasks and the cortical areas related to motor control (e.g., primary motor cortex, supplementary motor area) are probably the ones most affected by plastic changes. If the hypothesis turns out to be reliable, dancing, gymnastics, and other movement-rich activities are thoroughly encouraged for this purpose. Therefore, this approach might be used to attenuate GMD loss related to aging or another condition, such as Parkinson's and Alzheimer's., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Lateral preference is influenced by many different factors. Although studies that assessed handedness contributed greatly to our understanding of the phenomenon, looking to other dimensions of motor laterality, such as lower limbs, trunk, visual and hearing preference, may be an interesting strategy to further advance in the field. Comparing different age groups with a complete inventory also contributes to understanding the ageing impact on these variables. Our aim, therefore, was to assess six motor laterality dimensions in younger adults and older people. Two hundred subjects participated in this study (102 adults, 30.6 ± 11.2 years old, and 98 elders, 70.4 ± 7.22 years old) and lateral preference was assessed by the Global Lateral Preference Inventory. We verified significant differences between groups in all dimensions, except the visual one, with proportionally stronger right preference in the older group. Compared to other dimensions, higher frequency of ambidexterity was observed in trunk, hearing and visual preference for both groups. These results might indicate that lateral preference is, indeed, multifactorial, being affected by ageing, task complexity and other possible related aspects.

This study analyzed the effects of 12 weeks of resistance training (RT) on resting blood pressure (BP) and plasma levels of nitric oxide metabolites (NOx) in pre- and hypertensive older women, and evaluated the relationship between these 2 parameters. Thirty-five older women (68.2±5.7 years, 70.0±14.4 kg, 157.1±6.4 cm, 28.3±5.0 kg.m -2 ) were randomly allocated into a training group (TG; n=17), which performed a 12-week RT program, and a control group (CG; n=18), which did not perform any physical exercise. Anthropometry, one repetition maximum (1RM), body composition analysis by dual energy X-ray absorptiometry, blood samples, and resting BP were measured. There was a significant interaction for all variables analyzed, in which reductions of systolic BP (-8.5%), diastolic BP (-8.4%), and mean arterial pressure (-8.5%), and increases of NOx (+35.2%) were observed only for the TG. Moreover, a negative and significant correlation was observed (P<0.05; r=-0.63) between NOx and systolic BP in the TG. Results suggest that a 12-week RT program is sufficient to induce reductions in BP in pre- and hypertensive older women and that the decrease in systolic BP is associated with an increase in plasma NOx concentration., (© Georg Thieme Verlag KG Stuttgart · New York.)