Non-preferred Limbs Research Articles

Is the Rotatory Knee Stability Immediately Decreased Following a Competitive Soccer Match?

Fatigue induced by soccer playing increases physical efforts, which might alter the transverse knee stability, a known factor that promotes knee injuries, particularly anterior cruciate ligament injury. Thereby, primarily, we aimed to determine whether rotatory knee stability decreases immediately following a competitive soccer match in amateur players. Furthermore, we assessed the role of the preferred and non-preferred limbs to kick a ball in rotatory knee stability and the correlation between performance parameters and rotatory knee stability. We hypothesized that the knee stability decreases immediately after a competitive soccer match in amateur players. Eight healthy amateur soccer players (aged 27.2 ± 4.7 years and with body mass index of 23.8 ± 1.2 kg m−2) were included immediately before and after a competitive soccer match. The rotatory knee stability was assessed in the preferred and non-preferred limbs through the acceleration and jerk of the pivot shift maneuver and by the internal knee rotation of a pivoting landing task. Two-way repeated-measures ANOVA for factors time (before and after the soccer match) and limb (preferred and non-preferred) and multiple comparisons were performed using α = 5%. There was a statistical significance for the main factor time in the acceleration (5.04 vs. 6.90 ms−2, Δ = 1.86 ms−2, p = 0.020, η2 = 0.331) and jerk (18.46 vs. 32.10 ms−2, Δ = 13.64 ms−2, p = 0.004, η2 = 0.456) of the pivot shift maneuver. Rotatory stability decreases following a competitive soccer match in amateur soccer players under fatigue. Both the acceleration and jerk during the pivot shift maneuver is increased without significant internal knee rotation changes during the pivoting landing task.

Between-Limb Differences During 180° Turns in Female Soccer Players: Application of Statistical Parametric Mapping.

Thomas, C, Dos'Santos, T, Warmenhoven, J, and Jones, PA. Between-limb differences during 180° turns in female soccer players: application of statistical parametric mapping. J Strength Cond Res 36(11): 3136-3142, 2022-This study was exploratory in nature and investigated the ability of statistical parametric mapping (SPM) to assess between-limb differences in lower-extremity movement change of direction. Fourteen female soccer players (mean ± SD ; age = 20.6 ± 0.6 years; height = 1.65 ± 0.07 m; and body mass = 56.04 ± 6.20 kg). For comparisons between preferred and nonpreferred limbs, vertical (Fz) and horizontal (Fx) ground reaction force were determined along with hip, knee, and ankle angles and moments in the sagittal plane during weight acceptance during the final contact. In addition, frontal plane knee abduction angles and moments were calculated during the final contact. Statistical parametric mapping software was then used to assess for differences between the entire weight acceptance phase of preferred and nonpreferred limbs. There were no differences between limbs in all variables using SPM. These results demonstrate that female soccer players exhibit little side-to-side differences in certain lower-limb biomechanics when performing a turn maneuver. These findings can be utilized by practitioners and clinicians when developing injury prevention and rehabilitation programs.

Running after cycling induces inter-limb differences in muscle activation but not in kinetics or kinematics

ABSTRACT Overuse injuries are a common problem to triathletes’ population. Overuse injuries may arise from inter-limb biomechanical differences during running, but the literature lacks information regarding inter-limb differences in triathletes. In this study inter-limb differences were investigated in injury-free triathletes during the running portion of a simulated cycle-run transition. Thirteen triathletes performed a 5 km run preceded by a 20 min cycling trial at 70% of maximal power output. During the Start, Mid and End stages of running, kinetic, kinematic and muscle activation variables were compared between the preferred and non-preferred limbs across the stance phase. A statistical parametric mapping analysis showed no differences between limbs when considering kinetic and kinematic variables (p > 0.05, ES<0.60). A lower soleus activation was observed in the preferred limb (p < 0.05, ES>0.60) from 53.40–75.9% of the stance phase at the End stage of running. In conclusion, inter-limb differences in kinetic or kinematic variables may not represent a risk for overloading in triathletes. However, inter-limb differences in triceps surae activation during running after cycling may represent one potential factor leading to overuse injuries in triathletes and should be further investigated.

Cross-lateralisation in children with attention-deficit/hyperactivity disorder and motor skill performance.

Cross‐lateralisation and increased motor difficulties have been reported in children with attention‐deficit/hyperactivity disorder (ADHD). Nevertheless, the question of how crossed (i.e. mixed preference) or uncrossed (i.e. same side preference) lateralisation impacts motor performance in children with ADHD has yet to be examined. In this study, previously validated observational measures of hand and foot preference were used to identify right‐handed children with ADHD who display cross‐ (n = 29) and uncross‐lateralisation (n = 31). An uncross‐lateralised typically developing (TD) group (n = 32) was also identified, and included as a control. Motor performance was assessed with seven valid and reliable fine and gross motor tasks performed with both preferred and non‐preferred limbs. Group, task and sex‐related effects were examined. Findings revealed that male (but not female) cross‐lateralised children with ADHD performed significantly worse, respectively, in two of the fine motor tasks (spiral tracing [p < .01], and dot filling [p < .05]). Results suggest that cross‐lateralised hand and foot preference may affect complex motor skills in male children with ADHD. Furthermore, characteristics of ADHD may manifest differently in male and female children. Findings highlight the importance of considering both hand and foot preference when targeting motor interventions for children with ADHD.

The effect of limb preference on braking strategy and knee joint mechanics during pivoting in female soccer players

ABSTRACTPurpose: The purpose of this study was to explore whether limb preference influences braking strategy and knee joint mechanics during a 180° pivot task in female soccer players.Methods: Three-dimensional motion analyses of pivoting on the preferred and non-preferred kicking limbs were performed using 10 Qualisys ‘Oqus 7ʹ infrared cameras (240 Hz). Ground reaction forces (GRF) were collected from two AMTI force platforms (1200 Hz) embedded into the running track to examine penultimate (PEN) and final (FC) contact.Results: Both preferred and non-preferred limbs involved greater hip (ES = 2.85–3.81) and knee joint flexion angles (ES = 5.74–5.78) and peak vertical GRFs (ES = 0.87–1.61), but lower average vertical (ES = 2.55–3.01) and horizontal GRFs (ES = 3.05–3.67) during the PEN compared to the FC. Knee abduction angles were very likely greater (ES = 0.61) when turning off the non-preferred limb compared to the preferred limb.Conclusion: These findings may help us question the role of limb preference during pivoting, yet knee abduction angles and moments should be monitored with caution in female soccer players. Thus, it remains inconclusive the role limb preference plays in change of direction biomechanics for performance and risk of injury.

ISOKINETIC ASSESSMENT OF MUSCULAR STRENGTH AND BALANCE IN BRAZILIAN ELITE FUTSAL PLAYERS

Strength asymmetries are related to knee injuries in intermittent sports players. The purpose of this study was to examine whether elite futsal players demonstrate strength asymmetries during knee isokinetic testing applying the Croisier et al.21 criteria. Forty male elite (27.9 ± 6.5 years) Brazilian futsal players participated in the study. The testing protocol required players to perform concentric contractions of both quadriceps and hamstring muscles at angular velocities of 60 °·s-1 and 240 °·s-1 and eccentric contractions of hamstring at 30 °·s-1 and 120 °·s-1. Conventional (concentric:concentric) and mixed (eccentric:concentric) hamstrings/quadriceps (H/Q) ratios were calculated. Subjects were determined to have an imbalanced strength profile if an athlete had at least two parameters that were asymmetrical across speeds and conditions. Asymmetry was operationally defined as peak torque asymmetry greater than 15% in bilateral comparison, and H/Q ratio less than 0.47 for conventional and 0.80 for mixed conditions. Significant differences were observed between preferred and nonpreferred limbs in the concentric contractions of flexors at 240 °·s-1 and eccentric contractions of extensors and flexors at 30 °·s-1 and 120 °·s-1. However, these asymmetries did not exceed 15%. The conventional and mixed H/Q ratios were greater in the preferred than in nonpreferred limbs, but only the mixed hamstringsecc/quadricepsconc in the nonpreferred limbs showed values lower than recommended (<0.80). In addition, 50% of elite futsal players had preseason strength imbalances per the developed criteria. The studied elite futsal players had preseason strength imbalances, which may increase the risk of hamstring injuries. 3.

Strength and Power Acute Responses to Suspension Training

Suspension Training (ST) is a form of resistance training aiming at improving strength, endurance, coordination, flexibility, power, and core stability. Although ST is thought to elicit higher muscle activations than traditional exercises, only limited information is available on its acute effects on strength and power performances. PURPOSE: To evaluate strength and power acute responses after group ST in relation to gender. METHODS: 32 college students (16 M, 16 F; Age: 25.8±3.9years; Body Mass: 65.8±11.2Kg; Height: 166.9±8.9cm; BMI: 23.5±2.4kg/m2) volunteered to participate in the study. Before (PRE) and after (POST) a 45-min ST group session, Squat (SJ) and Countermovement (CMJ) Jumps were performed on a portable force plate, while lower limb Maximum Voluntary Contraction (MVC) at 90° angle isometric knee extension and grip strength (HG) were measured in preferred and non-preferred limbs through a piezoelectric force transducer and a hydraulic hand dynamometer, respectively. ANOVA for repeated measures was use to evaluate differences (p<0.05) in relation to gender and experimental session. RESULTS: As expected, M always showed highest strength and power values (p<0.02). In the POST condition, no significant improvements were found for HG, with best performances (p<0.02) emerging for the preferred limb (M-PRE: 429.3±31.2N; M-POST: 445.7±30.2N; F- PRE: 254.1±12.6N; F- POST: 256.4±13.5N) with respect to the non-preferred one (M-PRE: 399.4±16.2N; M-POST: 407.6±28.6N; F-PRE: 231.7±15.9N; F-POST: 236.1±18.1N). For MVC, only F showed differences between limbs (p<0.02), with highest values in the preferred leg (PRE: 238.8±15.1N; POST: 246.9±20.1N) and lowest in the non-preferred one (PRE: 222.4±19.9N; POST=230.9±14.5 N). After the session, M only showed improvements (p<0.02) in CMJ (PRE: 32.3±1.8cm; POST: 33.7±1.7cm) and MVC for the non-preferred leg (PRE: 276.1±16.6N; POST: 292.4±24.1N), while no differences emerged for SJ. CONCLUSIONS: Results shown that ST is a form of exercise useful to maintain and improve acute strength and power performances, in particular in male subjects. ST could be added in warm-up programs for sports where strength and power are key components.

Are the Responses to Resistance Training Different Between the Preferred and Nonpreferred Limbs?

Humans preferentially recruit limbs to functionally perform a range of daily tasks, which may lead to performance asymmetries. Because initial training status plays an important role in the rate of progression during resistance training, could asymmetries between the preferred and nonpreferred limbs lead to different magnitudes of strengthening during a resistance training program? This issue motivated this study, in which 12 healthy and physically active men completed a 4-week control period followed by a 12-week isokinetic resistance training program, performed twice a week, including 3-5 sets of 10 maximal eccentric contractions for each limb. Every 4 weeks, knee extensor peak torques at concentric, isometric, and eccentric tests were measured using an isokinetic dynamometer and the sum of quadriceps muscle thickness was determined by ultrasound images. Before training, concentric peak torque was similar between limbs but isometric and eccentric peak torques were significantly smaller in the nonpreferred compared with the preferred limb (4.9 and 5.8%, respectively). Bilateral strength symmetry remained constant throughout the training period for concentric tests. For eccentric and isometric tests, symmetry was reached at the fourth and eighth training weeks, respectively. After 12 weeks, between-limb percent nonsignificant differences were -0.62% for isometric and -1.93% for eccentric tests. The sum of knee extensor muscle thickness had similar values before training and presented similar changes throughout the study for both the preferred and the nonpreferred limbs. In conclusion, the nonpreferred limb presents higher strength gain than the preferred limb at the initial phase of an isokinetic resistance training program, and this increased strength gain is not associated with muscle hypertrophy.

Aiming accuracy in preferred and non-preferred limbs: implications for programing models of motor control

Most models of motor programing contend that one can perform learned actions with different muscle groups or limbs demonstrating the concept of motor equivalence. The goal of this review is to determine the generality of this concept within the context of aiming movements performed by both preferred and non-preferred limbs. Theoretical approaches to motor programing are described, followed by a comparison of a variety of kinematic measures taken from preferred and non-preferred limbs from simple and more complex aiming tasks. In general, the support for motor equivalency is strong for one- and two-dimensional aiming tasks and for simultaneous bimanual movements, but mixed for unconstrained throwing tasks and tasks that require feedback-based corrections.

Three-dimensional kinematic differences between the preferred and non-preferred limbs during maximal instep soccer kicking

The current investigation aimed to determine whether there are differences in ball velocity and 3D kinematics when performing maximal kicks with the dominant and non-dominant limbs. Seventeen male academy soccer players performed maximal speed place kicks with their dominant and the non-dominant limbs. The 3D kinematics of the lower extremities were obtained using a 10-camera motion capture system operating at 500 Hz. Hip, knee and ankle joint kinematics were quantified in the sagittal, coronal and transverse planes and then contrasted using paired t-tests. Significantly higher ball velocities were obtained with the dominant limb. Foot linear velocity and knee extension velocity at ball contact were also found to be significantly greater in the dominant limb. That reduced ball velocities were observed between kicking limbs highlights the potential performance detriments that may occur when kicking with the non-dominant limb; thus, it is recommended that additional bilateral training be undertaken in order to attenuate this and improve overall kicking performance.

Differences in plantarflexor function during a stretch-shortening cycle task due to limb preference

Most healthy humans move symmetrically at gross limb level but large kinetic and kinematic asymmetries have been observed at joint level during locomotion. The aim of this study was to assess muscle function asymmetries in healthy, active adults using an adapted force sledge apparatus which isolates the plantarflexors during a stretch-shortening cycle (SSC) task. Peak force, rate of force development and SSC function of preferred and non-preferred limbs were assessed in 21 healthy, active individuals using the adapted sledge and three-dimensional motion analysis. Between-limb differences and relationships were determined using paired t-tests/Wilcoxon Signed-rank test, Cohen's dz, absolute symmetry index and Pearson's r/Spearman's rho. Significant differences with moderate effect size (ES) were observed in peak force (ES: 0.66), rate of peak force development (ES: 0.78), rate of force development in the first 50 ms (ES: 0.76), flight time (ES: 0.64) and SSC function (0.68), with no difference in contact time or duration of eccentric loading. A small ES (0.56) was observed in rate of force development in the first 30 ms. The upper range of asymmetry observed (up to 44.6%) was larger than previously reported for healthy individuals, indicating compensations occur at proximal joints during locomotion to ensure symmetrical movement.

Gait asymmetry during dual-task obstacle crossing in the young and elderly

PurposeTo evaluate gait asymmetry during obstacle crossing by young and elderly adults performing normal and dual-task gait.MethodsTen healthy young adults and ten elderly adults with mild cognitive impairment performed a gait protocol by stepping over a foam obstacle during normal gait and while performing a secondary task (Stroop task). Sagittal kinematics of the lead and trail limbs were analyzed. Statistical procedures involved analysis of variance and t tests at a significance of 0.05.ResultsMany of the kinematic variables presented a main effect for group (young adults vs. elderly adults), where the elderly featured poorer gait performance. It was observed that gait velocity during obstacle crossing in normal and dual-task gait was similar between the preferred and non-preferred limbs in both the young and elderly. However, the elderly were slower during normal and dual-task gait. A main effect for the dual-task condition was observed. Kinematic asymmetries for obstacle crossing were more frequent in the elderly and especially during the dual-task condition.ConclusionsThe results suggest that the elderly may require more compensatory adjustments after crossing an obstacle. The asymmetries observed among the elderly may contribute to higher risk of falling during perturbed gait.

Preference and torque asymmetry for elbow joint

Extensively unilateral recruitment for daily activities may determine performance asymmetries in favor of the preferred side eliciting functional adaptation. Our study evaluated asymmetries in elbow torque output between preferred and non-preferred limbs. Eighteen subjects performed maximal elbow flexor and extensor isometric contractions at five different elbow joint angles (0º, 30º, 60º, 90º, 120º) and five different angular velocities (60, 120, 180, 240, 300º.s-1) on an isokinetic dynamometer. Higher flexor torque in favor of preferred arm was observed at 90º of flexion (p&lt;0.05), which also corresponded to the highest torque produced (p&lt;0.05). The fact that joint angle influenced torque asymmetries, whereas angular velocity did not, suggest that the observed asymmetry is likely related to preferential recruitment of elbow flexors at a 90º joint angle for daily tasks requiring high levels of force production. Muscle functional adaptation to frequent stimuli at this joint angle in healthy subjects may explain these results.

Characteristics of the Performance of a Formed Motor Skill by Rats with Different Motor Preferences

Wistar rats with different motor preferences were used to study performance of a food-procuring skill--extracting food from a narrow horizontal feeder tube. These experiments showed that when the preferred limb was used, left-handed rats performed the task more quickly (including both preliminary movements and the final successful movements) than right-handed rats. Comparison of movement performance times with the preferred and non-preferred limbs showed that the task was performed more quickly using the left paw in both left- and right-handed rats, i.e., independently of whether this was the preferred paw or not. At the final stage of task performance (grasping and extracting the food), the preferred paw was more successful than the non-preferred paw in both right- and left-handed animals. It is suggested that the organization of the overall strategy for performing this complex behavioral task in rats is determined by the functional heterogeneity of the right and left hemispheres of the brain, which is not linked with limb preference. The selected preference is based on the specific motor and precision characteristics of the preferred paw, while the contralateral hemisphere--the left in right-handed animals and the right in left-handed animals--has a special role in mediating these abilities.

Strength Training Improves the Tri-Digit Finger-Pinch Force Control of Older Adults

Keogh JW, Morrison S, Barrett R. Strength training improves the tri-digit finger-pinch force control of older adults. Objective To investigate the effect of unilateral upper-limb strength training on the finger-pinch force control of older men. Design Pretest and post-test 6-week intervention study. Setting Exercise science research laboratory. Participants Eleven neurologically fit older men (age range, 70–80y). Intervention The strength training group (n=7) trained twice a week for 6 weeks, performing dumbbell bicep curls, wrist flexions, and wrists extensions, while the control group subjects (n=4) maintained their normal activities. Main Outcome Measures Changes in force variability, targeting error, peak power frequency, proportional power, sample entropy, digit force sharing, and coupling relations were assessed during a series of finger-pinch tasks. These tasks involved maintaining a constant or sinusoidal force output at 20% and 40% of each subject’s maximum voluntary contraction. All participants performed the finger-pinch tasks with both the preferred and nonpreferred limbs. Results Analysis of covariance for between-group change scores indicated that the strength training group (trained limb) experienced significantly greater reductions in finger-pinch force variability and targeting error, as well as significantly greater increases in finger-pinch force, sample entropy, bicep curl, and wrist flexion strength than did the control group. Conclusions A nonspecific upper-limb strength-training program may improve the finger-pinch force control of older men.

Heart Rate and Blood Lactate during Official Female Motorcycling Competitions

The aim of this study was to investigate the physiological load of free practices (F), qualifying sessions (Q), and official races (R) of motorcycling competitions. Twenty-six female riders (age: 30.8 +/- 6.1 yrs) participated in this study. Anthropometric and strength evaluations were performed. Subject's heart rate (HR) was continuously recorded during three periods (5-minute Pre, Ride, and 5-minute Post) of the F, Q, and R phases of competitions. Blood lactate concentrations (La) were determined at rest and after riding. Riders had 56.5 +/- 6.7 kg of body mass, 164 +/- 4 cm of height, 21.6 +/- 4.4 % of body fat, and a BMI of 20.9 +/- 2.3 kg . (m (2)) (-1). Significant handgrip differences were found between the preferred (307 +/- 32 n) and non-preferred (281 +/- 47 N) limbs. During riding, frequency of occurrence of HR >or= 90 % HR (max) was 67 % in F, 74 % in Q, and 83 % in R. La after ridings (4.8 +/- 2.6 mmol . l (-1)) was two-folds (p < 0.05) the basal values (2.2 +/- 0.5 mmol . l (-1)), independently from the competition phases. The present HR and La data show that female road race motorcycling imposes a very intensive physical strain to the riders who need to control their motorbikes while performing frequent accelerations and decelerations.

Homolateral Hand and Foot Coordination in Trained Older Women

Background: Age-related deterioration in homolateral hand and foot coordination might be due to the combined effects of aging and a sedentary lifestyle. Unfortunately, there is a lack of information regarding the effects of training programs on coordinated inter-limb behavior with advancing age. Objective: The aim of the present study was to verify differences in homolateral hand and foot coordination between trained and untrained older women. Methods: Fifteen sedentary older women were matched in age (61–70 years) with 15 older women who had trained for at least 7 years with 3 one-hour sessions/week of rhythmic gymnastics. The subjects performed simultaneous flexions and extensions of the homolateral wrist and ankle in the sagittal plane at a 1:1 ratio. Two homolateral conditions (preferred and non-preferred limbs) were tested in two coordination modes: in-phase (isodirectional) and anti-phase (non-isodirectional) at three test frequencies (80, 120, and 180 bpm, respectively). The time of correct execution within a maximum of 60 s was recorded for each test condition. Results: Sedentary older women maintained the required movements for a shorter time than older gymnasts, especially with increasing execution frequency and in the anti-phase condition. Older gymnasts showed no negative effects of increasing frequency on coordination performance in the in-phase mode, and frequency-related performance decrements of lower magnitude than sedentary older women in the anti-phase mode. Conclusion: The present results indicate that the beneficial effects of rhythm-based training can be better understood when both the spatial and temporal constraints of the inter-limb coordination performance are considered. In fact, trained women largely succeeded in maintaining temporal constraints of in-phase inter-limb coordination even at the highest execution frequency, whereas sedentary women performed worse than trained women already at the lowest frequency. Furthermore, only trained women still succeeded in the anti-phase conditions. Thus, it appears that regular and prolonged practice of rhythmic gymnastics enhances inter-limb performance over both a sedentary lifestyle as well as ageing.

Field Evaluation of Cycled Coupled Movements of Hand and Foot in Older Individuals

Background: Age-related deterioration of motor performance has been investigated, often associated to behavioral slowing and to modification in the quality of movement coordination. However, the complexity of laboratory settings restrains sound quantitative evaluation of inter-limb coordination in large-scale clinical assessments, and no information regarding test stability has been provided. Objective: The aims of the present study were to verify in homolateral hand and foot coordination field performances: (1) acceptable test–retest reliability criteria for older adults, and (2) the effects of coordination mode and test velocity at different ages across lifespan. Methods: Seventy-seven individuals, ranging in age from 10 to 87 years, performed simultaneous flexions and extensions of the homolateral wrist and ankle in the sagittal plane with a 1:1 ratio. Two homolateral conditions (preferred and non-preferred limbs) were tested in two coordination modes: in-phase (isodirectional) and anti-phase (nonisodirectional) at three test frequencies (80, 120 and 180 bpm, respectively). Time of correct execution within a maximum of 60 s was recorded for each test condition. Older adults (n = 36) performed the test and the retest with a week interval. Results: High ICCs (range 0.72–0.98) and acceptable limits of agreement were found for the subsample of older adults. Main effects and significant interactions were found for age, coordination mode, and execution frequency. Time of correct execution was longest in younger adults and shortest in older individuals. At all ages, it was longer for the in-phase than in the anti-phase condition and decreased with increasing execution frequency. However, the amplitude of the differences between execution frequencies varied as a function of age and coordination mode. Conclusions: The high test-retest stability coefficients confirm that the present field test represents a reliable tool to quantify older individual’s performance on cyclic coupled movements of hand and foot allowing large-scale evaluations with an inexpensive apparatus. Aging generally harms homolateral inter-limb coordination performance, but a more complex pattern of effects emerges when coordination mode, and frequency of execution are manipulated. In fact, age-related performance impairments were most pronounced during anti-phase movements, that need increased monitoring and attentional allocation in order to inhibit the natural in-phase mode, and at high execution frequencies, that are strongly affected by age-related muscle weakness, prolonged reaction times, and changes in stretch reflexes.

Bilateral symmetry in coincident timing: a preliminary investigation.

The purpose of this study was to investigate the coincident timing accuracy of the preferred and nonpreferred limbs in a ballistic striking task. A secondary purpose was to examine subjects' perception of their performance proficiency with each limb. 30 right-hand preferred subjects performed a 60-cm horizontal arm motion to displace a wooden barrier in coincidence with the final light in a series that traveled down a runway. Interestingly, while both the preferred and nonpreferred limbs were equally proficient in temporal accuracy, 80% of subjects perceived a bilateral asymmetry in performance. The influence of this perception on bilateral skill performance and acquisition remains in question.

Foot-Tapping Speed in Children Ages 4 to 6 Years

This investigation examined the performance and measurement characteristics of foot-tapping speed in 155 4- to 6-year-olds. Analysis suggested that, while the task does not differentiate between preferred and nonpreferred limbs, performance does appear to be age-related, that is, subjects tapped significantly faster with increasing age. Considering type of task and population, reliability was judged as moderate.