Effects of different swimming race constraints on turning movements

The aim of this study was to investigate the effects of different swimming race constraints on the evolution of turn parameters. One hundred and fifty-eight national and regional level 200-m (meters) male swimming performances were video-analyzed using the individualized-distance model in the Open Comunidad de Madrid tournament. Turn (p < .001, ES = 0.36) and underwater distances (p < .001, ES = 0.38) as well as turn velocity (p < .001, ES = 0.69) significantly dropped throughout the race, although stroke velocity and underwater velocity were maintained in the last lap of the race (p > .05). Higher expertise swimmers obtained faster average velocities and longer distances in all the turn phases (p < .001, ES = 0.59), except the approach distance. In addition, national level swimmers showed the ability to maintain most of the turn parameters throughout the race, which assisted them in improving average velocity at the end of races. Therefore, the variations in the turning movements of a swimming race were expertise-related and focused on optimizing average velocity. Turning skills should be included in the swimming race action plan.     

Relationships between coordination,active drag and propelling efficiency in crawl

This study examines the relationships between the index of coordination (IdC) and active drag (D) assuming that at constant average speed, average drag equals average propulsion. The relationship between IdC and propulsive efficiency (e_p) was also investigated at maximal speed. Twenty national swimmers completed two incremental speed tests swimming front crawl with arms only in free condition and using a measurement of active drag system. Each test was composed of eight 25-m bouts from 60% to 100% of maximal intensity whereby each lap was swum at constant speed. Different regression models were tested to analyse IdC–D relationship. Correlation between IdC and e_p was calculated. IdC was linked to D by linear regression (IdC = 0.246 · D − 27.06; R² = 0.88, P < .05); swimmers switched from catch-up to superposition coordination mode at a speed of ∼1.55 m s⁻¹ where average D is ∼110 N. No correlation between IdC and e_p at maximal speed was found. The intra-individual analysis revealed that coordination plays an important role in scaling propulsive forces with higher speed levels such that these are adapted to aquatic resistance. Inter-individual analysis showed that high IdC did not relate to a high e_p suggesting an individual optimization of force and power generation is at play to reach high speeds.     

Effect of aerobic training on inter-arm coordination in highly trained swimmers

The effect of three months of aerobic training on spatio-temporal and coordination parameters was examined during a swim trial at maximal aerobic speed. Nine male swimmers swam a 400-m front crawl at maximal speed twice: in trial 1, after summer break, and trial 2, after three months of aerobic training. Video analysis determined the stroke (swimming speed, stroke length, and stroke rate) and coordination (Index of Coordination and propulsive phase duration) parameters for every 50-m segment. All swimmers significantly increased their swimming speed after training. For all swimmers except one, stroke length increased and stroke rate remained constant, whereas the Index of Coordination and the propulsive phase duration decreased (p < .05). This study suggests that aerobic training developed a greater force impulse in the swimmers during the propulsive phases, which allowed them to take advantage of longer non-propulsive phases. In this case, catch-up coordination, if associated with greater stroke length, can be an efficient coordination mode that reflects optimal drag/propulsion adaptation. This finding thus provides new insight into swimmers’ adaptations to the middle-distance event.     

Do 5% changes around maximal lactate steady state lead to swimming biophysical modifications?

Our purpose was to examine the swimming biophysical responses at velocities (v) of 97.5, 100 and 102.5% of the maximal lactate steady state (MLSS). Ten elite female swimmers performed three-to-five 30-min constant tests at imposed paces to determine 97.5, 100 and 102.5%MLSS v. Gas exchange, blood lactate concentration ([La-]), stroke rate (SR) and v were determined during each test. The v values at 97.5, 100 and 102.5%MLSS were 1.21 ± 0.07, 1.24 ± 0.07 and 1.27 ± 0.07 m.s⁻¹, respectively. Oxygen uptake (V̇O₂) and Pulmonary ventilation (V̇E) increased as function of v. SR and stroke length (v/SR = SL) increased as a function of v. All measured variables were constant as a function of time at 97.5%MLSS and 100%MLSS. At 102.5%MLSS SR increased (3.5%) and stroke length (SL) decreased (3.5%) as a function of time. While V̇O₂ was constant at 102.5%MLSS, [La-] and V̇E increased as a function of time, suggesting hyperventilation, at v’s of 97.5%MLSS and 100%MLSS swimmers completed the 30 min swim in spite of decreased SL and increased SR. However, the decrease in SL and increased SF were accompanied by increased [La-] and V̇E and resulted in the inability of most swimmers to complete the 30 min swim presumably due to fatigue at 102.5%MLSS.     

Evolution of match performance parameters for various playing positions in the English Premier League

This study aimed to investigate position-specific evolution of physical and technical performance parameters in the English Premier League (EPL). Match performance observations (n = 14700) were collected using a multiple-camera computerized tracking system across seven seasons (2006–07 to 2012–13). Data were analyzed relative to five playing positions: central defenders (n = 3792), full backs (n = 3420), central midfielders (n = 3200), wide midfielders (n = 2136) and attackers (n = 2152). High-intensity running distance increased in the final season versus the first season in all playing positions (p < .05, ES: 0.9–1.3) with full backs displaying the greatest increase (∼36% higher in 2012–13). Similar trends were observed for sprint distance with full backs demonstrating the most pronounced increase across the seven seasons (36–63%, p < .001, ES: 0.8–1.3). Central players (central defenders and midfielders) illustrated the most pronounced increases in total passes and pass success rate (p < .05, ES: 0.7–0.9) whilst wide players (full backs and wide midfielders) demonstrated only small-moderate increases in total passes and pass success rate (p < .05, ES: 0.6–0.8). The data demonstrates that evolving tactics in the EPL have impacted on the physical demands of wide players and the technical requirements of central players. These findings could be used for talent identification or position-specific physical and technical training.     

Quantification of upper limb kinetic asymmetries in front crawl swimming

This study aimed at quantifying upper limb kinetic asymmetries in maximal front crawl swimming and to examine if these asymmetries would affect the contribution of force exertion to swimming performance. Eighteen high level male swimmers with unilateral breathing patterns and sprint or middle distance specialists, volunteered as participants. A load-cell was used to quantify the forces exerted in water by completing a 30 s maximal front crawl tethered swimming test and a maximal 50 m free swimming was considered as a performance criterion. Individual force–time curves were obtained to calculate the mean and maximum forces per cycle, for each upper limb. Following, symmetry index was estimated and breathing laterality identified by questionnaire. Lastly, the pattern of asymmetries along the test was estimated for each upper limb using linear regression of peak forces per cycle. Asymmetrical force exertion was observed in the majority of the swimmers (66.7%), with a total correspondence of breathing laterality opposite to the side of the force asymmetry. Forces exerted by the dominant upper limb presented a higher decrease than from the non-dominant. Very strong associations were found between exerted forces and swimming performance, when controlling the isolated effect of symmetry index. Results point that force asymmetries occur in the majority of the swimmers, and that these asymmetries are most evident in the first cycles of a maximum bout. Symmetry index stood up as an influencing factor on the contribution of tethered forces over swimming performance. Thus, to some extent, a certain degree of asymmetry is not critical for short swimming performance.     

Effectuation of adaptive stability and postural alignment strategies are decreased by alcohol intoxication

Human stability control is a complex process comprising contributions from several partly independent mechanisms such as coordination, feedback and feed-forward control, and adaptation. Acute alcohol intoxication impairs these functions and is recognized as a major contributor to fall traumas. The study aimed to investigate how alcohol intoxication at .06% and .10% blood alcohol concentration (BAC) affected the movement spans and control of posture alignment. The angular positions of the head, shoulder, hip and knees relative to the ankles were measured with a 3D motion analysis system in 25 healthy adults during standing with eyes open or closed and with or without vibratory balance perturbations.Alcohol intoxication significantly increased the movement spans of the head, shoulders, hip and knees in anteroposterior and lateral directions during quiet stance (p ⩽ .047 and p ⩽ .003) and balance perturbations (p < .001, both directions). Alcohol intoxication also decreased the ability to reduce the movement spans through adaptation in both anteroposterior (p ⩽ .011) and lateral (p ⩽ .004) directions. When sober and submitted to balance perturbations, the subjects aligned the head, shoulders, hip and knees more forward relative to the ankle joint (p < .001), hence adopting a more resilient posture increasing the safety margin for backward falls. Alcohol intoxication significantly delayed this forward realignment (p ⩽ .022). Alcohol intoxication did not cause any significant posture realignment in the lateral direction. Thus, initiation of adaptive posture realignments to alcohol or other disruptions might be context dependent and associated with reaching a certain level of stability threats.     

Athletes trained using stable compared to unstable surfaces exhibit distinct postural control profiles when assessed by traditional and nonlinear measures

Athletes are assumed to exhibit better balance than non-athletes; however, few studies have examined the role of different types of sports on balance measures. Two athlete groups that experience divergent sport-specific balance training are stable- (i.e. basketball) and unstable-surface athletes (i.e. surfers). The purpose of this study was to quantify the effect of stable- compared to unstable-surface sports on postural stability.MethodsEight non-athletes (NON), eight stable-surface athletes (SSA) and eight unstable-surface athletes (USA) performed five 20-s quiet standing trials while ground reaction forces were recorded. Approximate entropy (ApEn), total excursion and root mean square distances (RMS) of the center of pressure position were calculated. Univariate ANOVAs with post hoc tests were conducted for each variable.ResultsApEn values were lower in SSA compared to NON in the ML direction (p = 0.012) and USA had lower ApEn values compared to SSA in the AP direction (p = 0.036). The USA had smaller AP RMS compared to SSA (p = 0.002) while the USA had greater ML RMS (p = 0.008) and resultant RMS values compared to SSA (p = 0.025).DiscussionThese data suggest that USA and SSA may exhibit direction-specific differences in balance strategy due to feedback paradigm.     

The effects of autonomous difficulty selection on engagement,motivation, and learning in a motion-controlled video game task

This experiment investigated the relationship between motivation, engagement, and learning in a video game task. Previous studies have shown increased autonomy during practice leads to superior retention of motor skills, but it is not clear why this benefit occurs. Some studies suggest this benefit arises from increased motivation during practice; others suggest the benefit arises from better information processing. Sixty novice participants were randomly assigned to a self-controlled group, who chose the progression of difficulty during practice, or to a yoked group, who experienced the same difficulty progression but did not have choice. At the end of practice, participants completed surveys measuring intrinsic motivation and engagement. One week later, participants returned for a series of retention tests at three different difficulty levels. RM-ANCOVA (controlling for pre-test) showed that the self-controlled group had improved retention compared to the yoked group, on average, β = 46.78, 95% CI = [2.68, 90.87], p = 0.04, but this difference was only statistically significant on the moderate difficulty post-test (p = 0.004). The self-controlled group also showed greater intrinsic motivation during practice, t(58) = 2.61, p = 0.01. However, there was no evidence that individual differences in engagement (p = 0.20) or motivation (p = 0.87) were associated with learning, which was the relationship this experiment was powered to detect. These data are inconsistent with strictly motivational accounts of how autonomy benefits learning, instead suggesting the benefits of autonomy may be mediated through other mechanisms. For instance, within the information processing framework, the learning benefits may emerge from learners appropriately adjusting difficulty to maintain an appropriate level of challenge (i.e., maintaining the relationship between task demands and cognitive resources).     

A randomized controlled trial of strong minds: A school-based mental health program combining acceptance and commitment therapy and positive psychology

To date, most early intervention programs have been based on emotion regulation strategies that address dysfunctional cognitive appraisals, problem-solving skills, and rumination. Another emotion regulation strategy, ‘acceptance’ training, has largely been overlooked. To examine the efficacy of this strategy, a school-based mental health program combining positive psychology with acceptance and commitment therapy (Strong Minds) was evaluated in a randomized controlled trial with a sample of 267 Year 10 and 11 high-school students in Sydney, Australia. Mixed models for repeated measures examined whether the program led to reductions in symptoms amongst students who commenced the program with high depression, anxiety, and stress scores, and increased wellbeing scores amongst all students. Results demonstrated that compared to controls, participants in the Strong Minds condition with elevated symptom scores (n = 63) reported significant reductions in depression (p = .047), stress (p = .01), and composite depression/anxiety symptoms (p = .02) with medium to strong effect sizes (Cohen's d = 0.53, 0.74, and 0.57, respectively). Increased wellbeing (p = .03) in the total sample and decreased anxiety scores (p = .048) for students with elevated symptoms were significant for Year 10 students with medium effect sizes (Cohen's d = 0.43 and 0.54, respectively). This study tentatively suggests that including the emotion regulation strategy of acceptance in early intervention programs may be effective in reducing symptoms and improving wellbeing in high school students. Further research to investigate the generalizability of these findings is warranted.     

Use of video observation and motor imagery on jumping performance in national rhythmic gymnastics athletes

The aim of this study was to evaluate whether a mental training protocol could improve gymnastic jumping performance. Seventy-two rhythmic gymnasts were randomly divided into an experimental and control group. At baseline, experimental group completed the Movement Imagery Questionnaire Revised (MIQ-R) to assess the gymnast ability to generate movement imagery. A repeated measures design was used to compare two different types of training aimed at improving jumping performance: (a) video observation and PETTLEP mental training associated with physical practice, for the experimental group, and (b) physical practice alone for the control group. Before and after six weeks of training, their jumping performance was measured using the Hopping Test (HT), Drop Jump (DJ), and Counter Movement Jump (CMJ). Results revealed differences between jumping parameters F(1, 71) = 11.957; p < .01, and between groups F(1, 71) = 10.620; p < .01. In the experimental group there were significant correlations between imagery ability and the post-training Flight Time of the HT, r(34) = −.295, p < .05 and the DJ, r(34) = −.297, p < .05. The application of the protocol described herein was shown to improve jumping performance, thereby preserving the elite athlete’s energy for other tasks.     

Promoting an equitable and supportive school climate in high schools: The role of school organizational health and staff burnout

In response to persistent racial disparities in academic and behavioral outcomes between Black and White students, equitable school climate has drawn attention as a potential target for school reform. This study examined differences in Black and White students' experiences of school climate and explored whether indicators of school organizational health and staff burnout moderated differences in students' school experiences by race. Utilizing hierarchical linear modeling with a sample of 18,397 Black students (n = 6228) and White students (n = 12,169) and 2391 school staff in 53 schools, we found a consistent pattern of racial inequalities, such that Black students reported less positive experiences than White students across three indicators of school climate (caring γ = − 0.08, p < .001; equity γ = − 0.05, p = .007; and engagement γ = − 0.05, p < .001). In addition, we found significant, positive associations between aggregated staff-report of school organizational health and student-reported school climate (e.g., staff affiliation and student-perceived equity, γ = 0.07, p < .001). Surprisingly, a number of school organizational health indicators were more strongly associated with positive perceptions of school climate among White students than Black students, translating into greater racial disparities in perceived school climate at schools with greater organizational health (e.g., supportive leadership by race on student-perceived engagement, γ = − 0.03, p = .042). We also found negative associations between staff-reported burnout and students' experience of equity, such that the racial gap was smaller in schools with high ratings of burnout (γ = 0.04, p = .002). These findings have implications for educators and education researchers interested in promoting school social contexts that equitably support student engagement and success.     

Maternal postpartum depressive symptoms and infant externalizing and internalizing behaviors

Maternal postpartum depression has been shown to be one of the main predictors of externalizing and internalizing behaviors in toddlers and adolescents. Research suggests that presence of such behaviors can be observed as early as infancy. The current study uses longitudinal data from 247 mothers to examine the relationship between postpartum depressive symptoms at 8 weeks and the infant's externalizing and internalizing behaviors at 12 months. In unadjusted linear regression models, there were associations between postpartum depressive symptoms and infant externalizing behaviors (β = 0.082, SE = 0.032, p = 0.012) and internalizing behaviors (β = 0.111, SE = 0.037, p = 0.003). After controlling for potential confounding factors, including maternal age, race, education, home ownership, smoking status in the postpartum period, marital status, parenting stress, and happiness from becoming a parent, the associations between postpartum depressive symptoms and infant externalizing (β = 0.051, SE = 0.034, p = 0.138) and internalizing behaviors (β = 0.077, SE = 0.040, p = 0.057) were reduced and became non-significant. Furthermore, in these models the total amount of variance explained was 17.2% (p < 0.0001) for externalizing behaviors and 10.5% (p < 0.01) for internalizing behaviors; the only significant predictor of externalizing behaviors was maternal age (β = −0.074, SE = 0.030, p = 0.014), and of internalizing behaviors was white non-Hispanic ethnicity (β = −1.33, SE = 0.378, p = 0.0005). A combined effect of the confounding factors seems to explain the finding of no significant independent association between postpartum depressive symptoms and infant externalizing and internalizing behaviors.     

Relationships between match activities and peak power output and Creatine Kinase responses to professional reserve team soccer match-play

The specific movement demands of soccer that are linked to post-match recovery and readiness to train are unclear. Therefore, we examined the relationship between Global Positioning System (GPS) variables and the change (Δ; from baseline) in Creatine Kinase (CK) concentrations and peak power output (PPO; during the countermovement jump) at 24 h and 48 h post-match. Fifteen English Premier League reserve team players were examined over 1–4 matches. Measurements of CK and PPO were taken before (24 h prior to match-play) and after (+24 h and +48 h) each game during which movement demands were quantified using 10 Hz GPS data. High intensity distance covered (r = 0.386, p = 0.029; r = −0.349; p = 0.050), high intensity distance covered⋅min⁻¹ (r = 0.365, p = 0.040; r = −0.364, p = 0.040), high speed running distance (r = 0.363, p = 0.041; r = −0.360, p = 0.043) and the number of sprints⋅min⁻¹ (r = 0.410, p = 0.020; r = −0.368, p = 0.038) were significantly related to ΔCK and ΔPPO at +24 h post-match, respectively. No relationships were observed between any match variables and ΔCK and ΔPPO after +48 h of recovery. These findings highlight that high intensity match activities are related to ΔCK and ΔPPO in the 24 h, but not 48 h, following soccer match-play. Such information is likely of interest to those responsible for the design of soccer player’s training schedules in the days following a match.     

Flying without navigational aids – The case of commercial motorcyclists in Minna,Nigeria

The study investigated motorcycle operators in Minna city with a view to observing the riders’ signaling behavior and the presence or absence of navigational aids and their usage. The study was carried out in three stages. First, a 15 min rapid survey of 3135 motorcyclists was carried at both ends of three pre-selected busy roads with emphasis on observing the possession of navigational aids by the motorcyclists. Secondly, another set of study on signaling behavior was carried out in another three junctions within a 15 min period and finally an interview was conducted among 120 commercial and private motorcyclists from commercials and office parks for a more detailed study. The mean age and mean year of riding experience of the commercial motorcyclists were 28 (SD = 5.9) and 4 years (SD = 2.1) respectively compared to 32 (SD = 7.4) and 7 (SD = 7.4) years for private motorcyclists. The findings show that 18.1% of the motorcyclists had no trafficators and as high as 85.3% had no side mirrors. Of the 626 motorcyclists studied for signaling behavior, 574 (91.7%) failed to trafficate while turning at junctions. It was also found that 65 (54.2%) of the 120 motorcyclists interviewed had accidents with their motorcycles. Chi Squared test shows that effect of possession of side mirror on accident experience is not statistically significant (χ² = 2.11, p = .349) while possession of trafficators (χ² = 5.99, p = .050) and driving license (χ² = 12.603, p = .000) are statistically significant. The study revealed that 61.5% of motorcyclists that have trafficators had experienced accidents which points out the fact that riding behavior is more critical in road safety than having a perfect vehicle. The study recommends, among others, that the Federal Road Safety Corps and Vehicle Inspection Officers should be as strict with the motorcyclists as they are with the motorists in enforcing road safety.     

Perceiving red decreases motor performance over time: A pilot study

IntroductionColors may influence motor performance.ObjectiveThe present study aimed to compare the effects of perception of red and green environments on physical (performance and heart rate) and psychological (perceived effort, anxiety and enjoyment) parameters during cycling trials.MethodTen cyclists achieved two identical series of three randomized 7-minute trials on home trainers, during which they were continuously exposed to red, green, and gray environments. Covered distance and heart rate were recorded during each trial, after which participants answered items intended to assess perceived effort, anxiety, and enjoyment experienced during the trial.ResultsResults showed that covered distance (ps ≤ .02) and heart rate (ps ≤ .03) were lower in the red environment than in the gray and green environments. Enjoyment was higher in the green environment than in the red environment (p = .006). The colored environments did not influence perceived effort and anxiety (ps > .05).ConclusionThis study is the first to show that perceiving red is detrimental for motor performance over an extended period of time.     

Perception and action in swimming: Effects of aquatic environment on upper limb inter-segmental coordination

This study assessed perception–action coupling in expert swimmers by focusing on their upper limb inter-segmental coordination in front crawl. To characterize this coupling, we manipulated the fluid flow and compared trials performed in a swimming pool and a swimming flume, both at a speed of 1.35 m s⁻¹. The temporal structure of the stroke cycle and the spatial coordination and its variability for both hand/lower arm and lower arm/upper arm couplings of the right body side were analyzed as a function of fluid flow using inertial sensors positioned on the corresponding segments. Swimmers’ perceptions in both environments were assessed using the Borg rating of perceived exertion scale. Results showed that manipulating the swimming environment impacts low-order (e.g., temporal, position, velocity or acceleration parameters) and high-order (i.e., spatial-temporal coordination) variables. The average stroke cycle duration and the relative duration of the catch and glide phases were reduced in the flume trial, which was perceived as very intense, whereas the pull and push phases were longer. Of the four coordination patterns (in-phase, anti-phase, proximal and distal: when the appropriate segment is leading the coordination of the other), flume swimming demonstrated more in-phase coordination for the catch and glide (between hand and lower arm) and recovery (hand/lower arm and lower arm/upper arm couplings). Conversely, the variability of the spatial coordination was not significantly different between the two environments, implying that expert swimmers maintain consistent and stable coordination despite constraints and whatever the swimming resistances. Investigations over a wider range of velocities are needed to better understand coordination dynamics when the aquatic environment is modified by a swimming flume. Since the design of flumes impacts significantly the hydrodynamics and turbulences of the fluid flow, previous results are mainly related to the characteristics of the flume used in the present study (or a similar one), and generalization is subject to additional investigations.     

Relative effects of reduced weight and increased physical activity on hemoglobin A1c: Suggestions for behavioral treatments

Behavioral treatments for diabetes have often been unsuccessful and may benefit from a better understanding of the relative effects of two common treatment foci – decreased weight and increased volume of physical activity – on blood glucose. Overweight and obese adults (N = 59; M_age = 60 years) with hemoglobin A1c (HbA1c) values consistent with diabetes participated in a 6-month community-based behavioral treatment based on tenets of self-efficacy theory and social cognitive theory. The treatment was associated with significantly increased physical activity, reduced body mass index (BMI), and reduced HbA1c levels (ps < .001). Changes in BMI and physical activity accounted for a significant portion of the variance in change in HbA1c, R² = .13, p = .023. Change in volume of physical activity, β = ?.36, p = .007, but not change in BMI, β = ?.03, p = .792, significantly contributed to the variance in HbA1c change that was accounted for. There was no effect based on the sex of participants. Discussion focused on how findings might impact the efficacy, efficiency, and application of behavioral treatments for diabetes management.     

Walking impairs cognitive performance among people with multiple sclerosis but not controls

People with multiple sclerosis (MS) complain of problems completing two tasks simultaneously; sometimes called ‘dual-tasking’ (DT). Previous research in DT among people with MS has focused on how adding a cognitive task interferes with gait and few have measured how adding a motor task could interfere with cognition. We aimed to determine the extent to which walking affects a concurrent working memory task in people with MS compared to healthy controls. We recruited MS participants (n = 13) and controls (n = 10) matched by age (±3 years), education (±3 years) and gender. Participants first completed the cognitive task (subtracting 7’s from the previous number) and then again while walking on an instrumented walkway. Although there were no baseline differences in cognition or walking between MS participants and controls, MS participants demonstrated a 52% decrease in number of correct answers during DT (p < 0.001). Mental Tracking Rate (% correct answers/min) correlated strongly with MS-related disability measured using the Expanded Disability Status Scale (EDSS; r(11) = −0.68, p < 0.01). We propose that compromised mental tracking during walking could be related to limited neural resource capacity and could be a potentially useful outcome measure to detect ecologically valid dual tasking impairments.     

Increased forefoot loading is associated with an increased plantar flexion moment

The aim of this study was to identify the cascade of effects leading from alterations in force generation around the ankle joint to increased plantar pressures under the forefoot. Gait analysis including plantar pressure measurement was performed at an individually preferred and a standardized, imposed gait velocity in diabetic subjects with polyneuropathy (n = 94), without polyneuropathy (n = 39) and healthy elderly (n = 19). The plantar flexion moment at 40% of the stance phase was negatively correlated with the displacement rate of center of pressure (r = ?.749, p < .001 at the imposed, and r = ?.693, p < .001 at the preferred gait velocity). Displacement rate of center of pressure was strongly correlated with forefoot loading (r = ?.837, p < .001 at the imposed, and r = ?.731, p < .001 at the preferred gait velocity). People with a relatively high plantar flexion moment at 40% of the stance phase, have a faster forward transfer of center of pressure and consequently higher loading of the forefoot. This indicates that interventions aimed at increasing the control of the roll-off of the foot may contribute to a better plantar pressure distribution.