Motor Response Time Research Articles

Aromatic L‐Amino Acid Decarboxylase Gene Therapy Enhances Levodopa Response in Parkinson's Disease

BackgroundAs Parkinson's disease progresses, levodopa treatment loses efficacy, partly through the loss of the endogenous dopamine‐synthesizing enzyme L‐amino acid decarboxylase (AADC). In the phase I PD‐1101 study, putaminal administration of VY‐AADC01, an investigational adeno‐associated virus serotype‐2 vector for delivery of the AADC gene in patients with advanced Parkinson's disease, was well tolerated, improved motor function, and reduced antiparkinsonian medication requirements.ObjectivesThis substudy aimed to determine whether the timing and magnitude of motor response to intravenous levodopa changed in PD‐1101 patients after VY‐AADC01 administration.MethodsParticipants received 2‐hour threshold (0.6 mg/kg/h) and suprathreshold (1.2 mg/kg/h) levodopa infusions on each of 2 days, both before and approximately 6 months after VY‐AADC01. Infusion order was randomized and double blinded. Unified Parkinson's Disease Rating Scale motor scores, finger‐tapping speeds, and dyskinesia rating scores were assessed every 30 minutes for 1 hour before and ≥3 hours after start of levodopa infusion.ResultsOf 15 PD‐1101 patients, 13 participated in the substudy. Unified Parkinson's Disease Rating Scale motor score area under the curve responses to threshold and suprathreshold levodopa infusions increased by 168% and 67%, respectively, after VY‐AADC01; finger‐tapping speeds improved by 162% and 113%, and dyskinesia scores increased by 208% and 72%, respectively, after VY‐AADC01. Adverse events (mild/moderate severity) were reported in 5 participants during levodopa infusions pre–VY‐AADC01 and 2 participants post–VY‐AADC01 administration.ConclusionsVY‐AADC01 improved motor responses to intravenous levodopa given under controlled conditions. These data and findings from the parent study support further clinical development of AADC gene therapy for people with Parkinson's disease. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Development of a Mobile Phone App for Measuring Striking Response Time in Combat Sports: Cross-Sectional Validation Study.

BackgroundTReaction is a mobile app developed to determine strike response time at low cost and with easy application in combat sports. However, the validity and accuracy of the response time obtained by the TReaction app has not yet been evaluated.ObjectiveThis study aimed to test the validity and reliability of the TReaction app in measuring motor response time in combat sports.MethodsA total of two athletes performed 59 strikes to assess the response time upon visual stimulus using the TReaction app simultaneously with a high-speed camera. Accuracy of the measure was verified using a computer simulator programmed to discharge visual stimuli and obtain the response time. Pearson correlation, Student t test for dependent samples, and the Bland-Altman analysis were performed. Accuracy was verified using the intraclass correlation coefficient. Effect size (g) and the typical error of measurement (TEM) were calculated. The significance level was set at P<.05.ResultsNo significant difference (P=.56) was found between both systems. The methods presented a very strong correlation (r=0.993). The magnitude of differences was trivial (g<0.25), and TEM was 1.4%. These findings indicate a high accuracy between the computer screen and the mobile app measures to determine the beginning of the task and the response time.ConclusionsOur findings suggest that the TReaction app is a valid tool to evaluate the response time in combat sports athletes.

RESILIENCE AS AN INTEGRAL CHARACTERISTIC OF PERSONALITY AMONG CADETS OF EMERCOM OF RUSSIA

Relevance. Resilience as an integrative resource of an individual, determining its psychological stability was studied among cadets of the Emercom of Russia to develop a psycho correctional program and increase the effectiveness of vocational training and health maintenance.Intention. To develop a model of resilience based on the identification of associated personality manifestations among the cadets of EMERCOM of Russia.Methodology. The study was conducted on the basis of the Far Eastern Fire and Rescue Academy a branch of the St. Petersburg University State Emergency Service Ministry of Emergency Situations among 150 cadets of the faculty of fire safety aged 19–21 years. Psychodiagnostic methods were used as well as psychophysiological rehabilitation complex “REACOR” for biofeedback training and UPFT 1/30 “Psychophysiologist”.Results and their analysis. Parameters of life meaningfulness increase proportionally to resilience. The analysis of terminal values showed that cadets with low resilience sought freedom, financially secure life, pleasures, while cadets with high resilience opted for development, continuous physical and spiritual self improvement. Indicators of internal motivation according to K. Zamfir test were lower in cadets with low and medium resilience vs high resilience. External negative motivation in the group with lower resilience, on the contrary, was higher due to avoidance prevailing over external positive motivation. Adaptation to new or changing conditions is quite complicated for cadets with low resilience and can be disturbed depending on external circumstances. Low resilience was associated with pedantic, anxious, cyclothymic, excitable and dysthymic personality accentuations, medium resilience was associated with cyclothymic and demonstrative accentuations, and high – with hyperthymic and demonstrative accentuations. Cadets with low and medium resilience commonly used confrontational coping strategy. Cadets with low resilience showed increase in flight – avoidance strategies in contrast to those with medium and high resilience (p &lt; 0.05). Low resilience indicates a decrease in tension, the predominance of parasympathetic activity, pronounced inertness and passivity when performing tactical and technical actions. Cadets with high resilience demonstrated improved attention . Average and maximum response time was shorter in cadets with high resilience compared to those with low and medium resilience (p &lt; 0.01), which indicates an increased concentration, activity, and speed. Greater response time in cadets with low resilience probably indicates their passivity and inertness when completing tasks (p &lt; 0.01). After the heat chamber, average and maximum visual motor response time was longer in the group with low and medium resilience (p &lt; 0.05). The structure of resilience includes biological (psychophysiological), social and psychological components. The predictors of resilience are the meaningfulness of life, such coping behaviors as self control, acceptance of responsibility, flight avoidance; personal adaptive potential and its components behavioral regulation and communicative potential; rigid and emotive accentuations; external negative motivation; psychophysiological indicators – vagosympathetic balance (LF / HF), average reaction time.Conclusion. An experimental study of the psychological factors of reactions to professional stressors among cadets made it possible to draw up a scheme of resilience as an integral characteristic of a personality, and to reveal its components.

Central Sensitization, N-methyl-D-aspartate Receptors, and Human Experimental Pain Models: Bridging the Gap between Target Discovery and Drug Development.

Central Sensitization, N-methyl-D-aspartate Receptors, and Human Experimental Pain Models: Bridging the Gap between Target Discovery and Drug Development.

The relationship between leg stiffness, forces and neural control of the leg musculature during the stretch-shortening cycle is dependent on the anticipation of drop height.

This study aimed at investigating how prior knowledge of drop heights affects proactive and reactive motor control in drop jumps (DJ). In 22 subjects, the effect of knowledge of three different drop heights (20, 30, 40cm) during DJs was evaluated in seven conditions: three different drop heights were either known, unknown or cheated (announced 40cm, but actual drop height was 20cm). Peak ground reaction force (Fmax) to body weight (BW) ratio (Fmax/BW) and electromyographic (EMG) activities of three shank and five thigh muscles were assessed 150ms before and during ground contact (GC). Ankle, knee and hip joint kinematics were recorded in the sagittal plane. Leg stiffness, proactive and reactive EMG activity of the leg muscles diminished in unknown and cheat conditions for all drop heights (7-33% and 2-26%, respectively). Antagonistic co-activation increased in unknown (3-37%). At touchdown, increased flexion in knee (~ 5.3° ± 1.9°) and hip extension (~ 2° ± 0.6°) were observed in unknown, followed by an increased angular excursion in hip (~ 2.3° ± 0.2°) and knee joints (~ 5.6° ± 0.2°) during GC (p < 0.05). Correlations between changes in activation intensities, joint kinematics, leg stiffness and Fmax/BW (p < 0.05) indicate that anticipation changes the neuromechanical coupling of DJs. No dropouts were recorded. These findings underline that anticipation influences timing and adjustment of motor responses. It is argued that proactive and reactive modulations associated with diminished activation intensities in leg extensors are functionally relevant in explaining changes in leg stiffness and subsequent decline in performance.

How Long Is Too Long: An Individual Time-Window for Motor Planning.

Human motor response time (RT) is determined by the matureness of the preceding neural motor planning process. In the current study, we characterize the temporal boundaries required for the motor planning process, and its impact on the overall motor RT. In particular, we contrasted short and long planning times by measuring the resulting differences in motor RTs, in an attempt to find whether an optimal planning time for minimal RT exists. Using a “Timed Response” paradigm, we presented participants with varying planning intervals prior to a requested motor response and studied their effect on the timing of initiation of the following movement. We found that, as expected, reaction time shortens as more planning time is provided, yet only until reaching a minimal RT, after which additional planning time increases the motor RT, thus creating a U-shaped behavioral function. Furthermore, since the minimal RT was found to be an individual characteristic, we suggest that there is an individual time window for motor planning.

Sarcasm between siblings: Children's use of relationship information in processing ironic remarks

We investigated whether children's appreciation of verbal irony is facilitated by the provision of speaker–addressee relationship information, namely that of a sibling relationship. We assessed both the product and process of children's interpretations to test whether children's processing of ironic remarks is better explained by sequential or interactive accounts of irony processing. Children (aged 5–8 years) viewed puppet shows in which the speaker and addressee were described either as siblings or as new acquaintances and the speaker made either an ironic or a literal remark. Using a variant of the visual world paradigm, participants were trained to make a motor response, selecting a response object to indicate whether they thought the speaker had a literal or an ironic intention. The timing of children's motor responses and their eye gaze to the response objects were tracked and analyzed. Results showed that sibling relationship information did not impact the accuracy of children's speaker intent judgments, but facilitated children's responding in the earliest stages of processing. We argue that these results are consistent with an interactive processing account of irony, by which cues to speaker intent are integrated early in the comprehension process.

Anticipation modulates neuromechanics of drop jumps in known or unknown ground stiffness.

With an emphasis on ballistic movements, an accurately anticipated neural control is an essential prerequisite to deliver a motor response coincidentally with the event of ground contact. This study investigated how previous knowledge of the ground condition affects proactive and reactive motor control in drop jumps (DJ). Thereby, human anticipatory capacity of muscle activation was investigated regarding neuromuscular activation, joint kinematics and peak forces associated with DJ performance. In 18 subjects, the effect of knowledge of two different surface conditions during DJs was evaluated. Peak force, ground-contact-time (GCT), rate of force development (RFD) and jump height were assessed. Electromyographic (EMG) activities of the m. soleus (SOL) and gastrocnemius medialis (GM) were assessed for 150ms before (PRE) and during ground contact (GC) for the short-, medium-, and long-latency responses. Ankle and knee joint kinematics were recorded in the sagittal plane.In the unknown conditions peak force, RFD and jump height declined, GCT was prolonged, proactive EMG activity (PRE) in SOL and GM was diminished (P<0.05). During GC, a decline in EMG activity in the unknown condition was manifested for SOL and GM for the SLR, MLR and LLR (P<0.05). Ankle and knee joint deflections during GC were increased in the unknown vs. known condition (P<0.05). Peak force, RFD and jump height were positively correlated to GM-EMG in PRE, SLR, MLR and LLR (P<0.05). Results revealed that proactive and reactive modulations in muscle activity prior and during GC are interrelated to the force-time characteristics and height of the jumps. The unknown condition revealed a comparable neuromuscular activity during pre-activation for both conditions, followed by an inhibition in the subsequent phase after touch down. These findings underline that anticipation is a determining factor influencing timing and adjustment of motor responses to accomplish ballistic movements regarding precision and performance.

Training using virtual reality improves response behavior in karate kumite

The aim was to study if sports-specific reaction training using immersive virtual reality improves the response behavior of karate athletes. During ten sessions, 15 experienced young karate athletes responded to upcoming attacks of a virtual opponent. On one hand, in PRE and POST tests, we examined the sports-specific response behavior using the time for response (time between a defined starting point and the first reaction), response accuracy (according to a score system), and kind of response (direct attack or a blocking movement) based on a movement analysis. On the other hand, we analyzed the unspecific response behavior using the reaction time and motor response time based on the reaction test of the Vienna test system. Friedman tests with subsequent Dunn–Bonferroni post-hoc tests and one-factorial ANOVAs showed no significant differences (p > 0.05) in the unspecific parameters. However, significant improvements (p < 0.05) of the sports-specific parameters were found, leading to a higher increase within the intervention groups (large effects) compared to the control groups (small and moderate effects in time for response, and no significant effects in response quality). It can be concluded that VR training is useful to improve response behavior in young karate athletes.

Examining the Interactions Between Expectations and tDCS Effects on Motor and Cognitive Performance.

Background: Despite a growing literature and commercial market, the effectiveness of transcranial direct current stimulation (tDCS) remains questionable. Notably, studies rarely examine factors such as expectations of outcomes, which may influence tDCS response through placebo-like effects. Here we sought to determine whether expectations could influence the behavioral outcomes of a tDCS intervention.Methods: Through an initial study and self-replication, we recruited 121 naïve young adults 18–34 years of age (M = 21.14, SD = 3.58; 88 women). We evaluated expectations of tDCS and of motor and cognitive performance at three times: (i) at baseline; (ii) after being primed to have High or Low expectations of outcomes; and (iii) after a single session of sham-controlled anodal tDCS over the left or right motor cortex. Before and after stimulation, participants performed the Grooved Pegboard Test and a choice reaction time task as measures of motor dexterity, response time, and response inhibition.Results: Repeated measures ANOVA revealed that participants had varying, largely uncertain, expectations regarding tDCS effectiveness at baseline. Expectation ratings significantly increased or decreased in response to High or Low priming, respectively, and decreased following the intervention. Response times and accuracy on motor and cognitive measures were largely unaffected by expectation or stimulation conditions. Overall, our analysis revealed no effect attributable to baseline expectations, belief of group assignment, or experimental condition on behavioral outcomes. Subjective experience did not differ based on expectation or stimulation condition.Conclusions: Our results suggest no clear effects of tDCS or of expectations on our performance measures, highlighting the need for further investigations of such stimulation methods.

고유수용성감각 강화훈련이 유소년 축구선수들의 무릎 관절위치감각, 운동반응시간 및 드리블능력에 미치는 영향

The purpose of this study was to investigate the changes of Joint Position Sense of the knee, motor response time and dribbling ability according to the proprioceptive training for 12 weeks in youth soccer players. The grouping was classified into a proprioceptive training group (PTG, n=10), a general training group (GTG, n=10) and a control group (CG, n=10). After the end of the experiment, statistical analysis was carried out as follows. There was a significant interaction effect on joint position sense of the knee (p.01). After post-hoc, PTG showed higher position sensory function than CG at 12 weeks. There was a significant interaction effect on reaction time (p.01). After post-hoc, PTG showed higher position sensory function than GTG and CG at 12 weeks. Dribbling ability did not show any significant interaction effect, but GTG and PTG showed significant dribble speed after 12 weeks compared to 0 week (p.01), (p.05). It is considered that the proprioceptive sensory strengthening training is a more effective exercise for improving joint position sense and reaction time and it is an important study result in the youth soccer player training program plan.

Visual load and variability of muscle activation: Effects on reactive driving of older adults

BackgroundThe functional significance of the increase in motor output variability with increased visual information processing in older adults remains unclear. Here, we test the hypothesis that increased visual information processing increases muscle activation variability in older adults and impairs their ability to react as fast and as precisely as young adults during a simulated reactive driving task. MethodsFourteen young and sixteen older adults performed a reactive driving simulation task that required responding to unexpected brake lights of the car ahead during a simple reaction time task (low visual information processing condition) and a choice reaction time task with “no go” trials condition (high visual information processing condition). We quantified the following: 1) reactive driving performance – combination of premotor response time, motor response time, and brake force error; 2) motor output variability – brake impulse variability; 3) muscle activation variability – variability in the tibialis anterior (TA) muscle activity. ResultsThe increase in information processing exacerbated the impaired reactive driving performance in older adults. The best predictor of this impairment was the increase in brake force error. The impaired reactive driving performance was related to brake impulse variability and variability in the TA activity. ConclusionsThis study provides novel evidence that increased information processing increases muscle activation variability in older adults with detrimental consequences to their ability to perform a simulated reactive driving task.

Simplified cerebellum-like spiking neural network as short-range timing function for the talking robot

ABSTRACTIn human speech, the timing function is important for determining its duration, stress and rhythm; however, little attention has been paid to these issues when building a speech synthesis system. In the human brain, the cerebellum plays a key role in the coordination, precision and timing of motor responses. We have developed a talking robot, which generates human-like vocal sounds using a simplified cerebellum-like neural network model as the timing function. The model was designed using the System Generator software in Matlab environment and the timing duration of trained speech was estimated using hardware co-simulated with a field programmable gate array board (FPGA). The timing information obtained from the co-simulation, together with the output motor vector, is sent to the talking robot controller in order to generate vowels of short, medium and long duration. Using this model for short-range timing of less than 1200 milliseconds, we verify that the short-range learning capability of the cerebellar-like neural network is applicable to the speaking robot for generating a human-like speech with prosodic features.

The Timing of Sensory-Guided Behavioral Response is Represented in the Mouse Primary Somatosensory Cortex.

Whisker-guided decision making in mice is thought to critically depend on information processing occurring in the primary somatosensory cortex. However, it is not clear if neuronal activity in this "early" sensory region contains information about the timing and speed of motor response. To address this question we designed a new task in which freely moving mice learned to associate a whisker stimulus to reward delivery. The task was tailored in such a way that a wide range of delays between whisker stimulation and reward collection were observed due to differences of motivation and perception. After training, mice were anesthetized and neuronal responses evoked by stimulating trained and untrained whiskers were recorded across several cortical columns of barrel cortex. We found a strong correlation between the delay of the mouse behavioral response and the timing of multiunit activity evoked by the trained whisker, outside its principal cortical column, in layers 4 and 5A but not in layer 2/3. Circuit mapping ex vivo revealed this effect was associated with a weakening of layer 4 to layer 2/3 projection. We conclude that the processes controlling the propagation of key sensory inputs to naive cortical columns and the timing of sensory-guided action are linked.

Effects of plyometric training on Electromyographic changes and jump shoot performance among female handball players

Success in many sports depends heavily on the athlete's explosive power and muscular strength. The athlete must be able to use strength as quickly and forcefully as possible. The purpose of this study was to investigate the influence of a 4-week plyometric training program on motor unit number and response time of muscles (upper and lower limbs) during jump shoot performance among female handball players. Three female handball players from the ELSHAMS club participated in this study. Subjects performed 4 – 6 sets of 20 repetition jumps from a 40-cm box and medicine ball exercises for three days a week for four weeks. The EMG activities in the lower extremity muscles, which include the vastus medialis (VM), rectus femoris (RF) vastus lateralis (VL), biceps femoris (BF), gastrocnemius – medial part(GMe), gastrocnemius lateral part (GLa), soleus (S) and tibialis anterior (TA), and upper extremity muscles, which include biceps brachi (BB), deltoid – anterior (BAn), deltoid - medial part (DMe), deltoid – rear part (DRe), extensors of the wrist (EW), erector spinae (ES), infras pinatus (IP) and latissimus dorsi (LD) muscles, during jump shoot performance were assessed pre- and post-training. The results showed significant increases in the EMG activities (IEMG) of all muscles following plyometric training (P < 0.05). The high increase was due to the motor units of the biceps femoris muscle (BF), 332%. In conclusion, plyometric training can significantly improve EMG activity and power among female handball players.

Relationship between the armed arm’s motor response and muscle activation time during the lunge in fencers of varied ability

The present work studied potential differences in activation times of selected muscles associated with the motor responses of the armed arm and differences in selected muscle pairs activation during the fencing lunge. Twenty-eight fencers (epee fencers, aged 22.1 ± 5.4 years) grouped into elite and beginning skill levels, participated in this study. Surface electromyography was used to determine muscle activation time (time period measured from visual stimulus occurrence to the moment of muscle activation threshold detection). For motor response, we measured the time between visual stimulus occurrence and armed arm movement. A significant difference was found between elite and beginning fencers in the motor response of the armed arm. Detection of armed arm’s motor response was significantly later in beginners. Greater time disparities between arm’s motor response and muscle activation time of the m. rectus femoris on the front/lunge side was also found in beginners. Lastly, difference was detected between elite and beginning fencers regarding the muscle activation time of selected muscle pairs. Future studies and trainers can use these results to further explore key areas of motor control and biomechanics for improving of fencing performance.

Targeted Neuromodulation of Abnormal Interhemispheric Connectivity to Promote Neural Plasticity and Recovery of Arm Function after Stroke: A Randomized Crossover Clinical Trial Study Protocol.

Background Despite intensive rehabilitation efforts, most stroke survivors have persistent functional disability of the paretic arm and hand. These motor impairments may be due in part to maladaptive changes in structural and functional connections between brain regions. The following early stage clinical trial study protocol describes a noninvasive brain stimulation approach to target transcallosally mediated interhemispheric connections between the ipsi- and contralesional motor cortices (iM1 and cM1) using corticocortical paired associative stimulation (ihPAS). This clinical trial aims to characterize ihPAS-induced modulation of interhemispheric connectivity and the effect on motor skill performance and learning in chronic stroke survivors. Methods/Design A repeated-measures, cross-over design study will recruit 20 individuals post-stroke with chronic mild–moderate paretic arm impairment. Each participant will complete an active ihPAS and control ihPAS session. Assessments of cortical excitability and motor skill performance will be conducted prior to and at four time points following the ihPAS intervention. The primary outcome measures will be: TMS-evoked interhemispheric motor connectivity, corticomotor excitability, and response time on a modified serial reaction time task. Discussion/Conclusion The findings from this single-site early stage clinical trial will provide foundational results to inform the design of larger-scale, multisite clinical trials to evaluate the therapeutic potential of ihPAS-based neuromodulation for upper limb recovery after stroke. This trial is registered with NCT02465034.

ВЛИЯНИЕ ПСИХОФИЗИОЛОГИЧЕСКИХ ПОКАЗАТЕЛЕЙ НА РЕЗУЛЬТАТ БЕГА НА 200 М У СПРИНТЕРОВ ВЫСОКОЙ КВАЛИФИКАЦИИ С НАРУШЕНИЕМ ЗРЕНИЯ НА ПРИМЕРЕ ЭЛИТНОЙ СПОРТСМЕНКИ

The aim of the work is to reveal the influence of psycho-physiological factors on the individual performance in a track and field sprint among highly qualified athletes with visual impairment on the example of an elite athlete. Material and methods. highly qualified athlete participated in the study, specializing in short-distance running and long jump among athletes with visual impairments in 2010 European Athletics Champion; winner of the World Paralympic Championships and the Paralympic Games for Athletes with Visual Impairment (Category T12) 2016. Psychophysiological testing athlete held close to the screen. The course of the study. The individual characteristics of the psychophysiological state and the results in the 200 m race for five months were analyzed. The results in the 200 m race were recorded at the official and unofficial competitions. A total of 36 results were analyzed. Results. Multiple linear regression models were compiled between results in a 200 m race for an elite athlete with visual impairment and psycho-physiological indicators. The selected model of multiple regression is represented by the following variables: simple visual motor response time (ms), total test time with feedback at 120 signals (s), time to reach the minimum signal exposure in a test with feedback at 30 signals (s) , the time to reach the minimum signal exposure in the test with feedback at 120 signals (s). Conclusions . The compensatory mechanisms of visual function insufficiency to maintain high speed in 200 m run as psycho-physiological functions were revealed: indicators characteristic of sprinters (simple reaction speed and mobility of the nervous system) and specific indicators (efficiency, strength of the nervous system).

Effect of In-water SCUBA Diving Activities on Response Time in Recreational Divers

The purpose of this study was to examine the relationship between the performance of in-water scuba diving training activities and simple motor response time. Twenty-four students enrolled in a scuba course had their motor response times measured before and after a one hour training session. Pre- and post-dive response times were measured using an iPad application. Additionally, students were asked to complete a dive history questionnaire to determine their diving experience and health history. Statistical analysis indicated a significant training effect on response time in the recreational scuba divers F (1.00, 23.00) p =.033. The results of this study suggest that basic in-water scuba training activities may improve one's ability to elicit quicker movement responses and lead to faster cognitive processing.

Sensory organisation and reactive balance control of amateur rugby players: A cross-sectional study

Purpose: This study compared the sensory organisation and reactive balance control of amateur rugby players and a control group. Methods: Forty-one amateur rugby players (22 males: 19 females; mean height ± SD = 168.8 ± 8.8 cm; mean weight ± SD = 63.9 ± 12.5 kg) and 31 control participants (22 males: 9 females; mean height ± SD = 171.5 ± 10.3 cm; mean weight ± SD = 63.8 ± 10.3 kg) completed the study. Their sensory organisation and standing balance performance were evaluated using a sensory organisation test (SOT), and their reactive balance performance was quantified using a motor control test (MCT). The SOT equilibrium scores (ES) and sensory ratios and the MCT motor response latencies were the major outcome measures. Results: The results revealed that compared to the controls, amateur rugby players had lower SOT ESs under different sensory environments (P < .001, = 0.142–0.254) and prolonged reactive motor response times in the MCT (P < .001, d = 0.890). The vestibular and visual ratios were also lower in the rugby group (P = .005, = 0.107 and 0.108, respectively). No significant difference was found in the somatosensory ratio (P = .853, < 0.001) between the two groups. Conclusions: Amateur rugby players demonstrated inferior standing balance performance compared to their non-trained counterparts. They relied less heavily on vestibular and visual inputs to maintain standing balance under different sensory environments. In addition, they reacted more slowly to postural disturbance, reflecting their suboptimal reactive balance ability in standing.