Stance Phase Of Running Research Articles

Immediate effects of shoe insoles on the frequency components of ground reaction force during the stance phase of running

Introduction: Foot insoles are widely recommended to prevent running related to injuries. However, their effects on the frequency of Ground Reaction Force(GRF) is still unclear. The purpose of this study was to elemental test the effect of four shoe insoles on frequency of GRF during stance phase of running. Materials and Methods: 15 female Students (mean age22±1/85 year, height162±4/71cm and weight56±5/59kg) were selected. Subjects were asked to run over a force plate, in a control and insole (normal, soft, semi rigid, rigid) conditions. Vertical and anterior-posterior (AP) of GRF were evaluated in frequency domain using fast furrier transformation. One factor repeated measures ANOVA was used to test the hypothesis. Results: The statistical results showed that there was a significant difference between insoles in 99.5% frequency of vertical (p=0/001), AP GRF (P=0/049), and median frequency of AP GRF (p=0/012). Conclusions: Increasing hardness of insoles reduces the 99/5% frequency power of GRF and median frequency of AP GRF. Accordingly, the 99/5% frequency power of GRF and median frequency of AP GRF can be an indicator of shoes insoles effects on the foot during running. Key words: Insole, Frequency, Power spectrum, Ground reaction force, Running

Design of a Clutch–Spring Knee Exoskeleton for Running

Because the leg is known to exhibit springlike behavior during the stance phase of running, several exoskeletons have attempted to place external springs in parallel with some or all of the leg during stance, but these designs have failed to permit natural kinematics during swing. To this end, a parallel-elastic exoskeleton is presented that introduces a clutch to disengage the parallel leg-spring and thereby not constrain swing-phase movements of the biological leg. A custom interference clutch with integrated planetary gear transmission, made necessary by the requirement for high holding torque but low mass, is presented and shown to withstand up to 190 N·m at 1.8 deg resolution with a mass of only 710 g. A suitable control strategy for locking the clutch at peak knee extension is also presented, where only an onboard rate gyroscope and exoskeletal joint encoder are employed as sensory inputs. Exoskeletal electromechanics, sensing, and control are shown to achieve design critieria necessary to emulate biological knee stiffness behaviors in running.

Ankle work and dynamic joint stiffness in high- compared to low-arched athletes during a barefoot running task

High- (HA) and low-arched (LA) athletes have an exaggerated risk of injury. Ankle joint stiffness is a potential underlying mechanism for the greater rate of injury within these two functionally different groups. An alternative candidate mechanism of injury in HA and LA athletes pertains to the efficacy of the foot as a rigid lever during propulsion. The purpose of this study was to quantify the differences in ankle dynamic joint stiffness, and ankle braking work and ankle propulsive work during stance phase of running. MethodsTen HA and ten LA athletes performed five barefoot running trials while ground reaction forces and three-dimensional kinematics were recorded. Ankle dynamic joint stiffness was calculated as the slope of the ankle joint moment–ankle joint angle plot during load attenuation. Ankle braking and propulsive work values were calculated for the stance phase. ResultsHA athletes had significantly greater ankle dynamic joint stiffness and significantly smaller ankle net and propulsive work than LA athletes. ConclusionsThese data demonstrate that HA and LA athletes exhibit unique biomechanical patterns during running. These patterns may be related to lower extremity injury.

Athletic footwear does not alter in-shoe hindfoot kinematics during overground running

Background: Heel counters are added to most athletic shoes under the premise that they control excessive hindfoot motion. However, it is oftenquestionedwhether this premisehas any scientific evidence. Although previous studies have described hindfoot kinematics during running, they have often used external shoe markers to infer in-shoe footmotionwhich is not a valid technique. The aim of this study was to compare hindfoot kinematics during running both barefoot and in typical running shoes. We hypothesised that running shoes would not alter hindfoot eversion motion but would reduce the rate at which it occurs (angular velocity). Methodology: Eighteen adults participated in this study (mean age 21.2±2.0 years, height 1.73±0.08m, bodymass 70.8±8.3 kg). Each participant completed five running trials both barefoot and wearing shoes (Asics Gel-Pulse 3). Kinematic data were acquired with a 12 camera VICON MXF-20 motion capture system (Vicon Motion Systems Ltd., Oxford, UK) at 100Hz. Variables of interest were the hindfoot eversion angle at initial contact and peak loading (15% stance), as well as the ROM and peak angular velocity during loading response (0–15% stance). Differences between conditions were compared using paired t-tests. Effect sizes (Cohen’s d) were also computed. Results: During running, footwear did not significantly reduce eversion of the hindfoot at initial contact (−7.59±5.69∞ vs. −6.15±5.59∞, p=>.05, ES =0.26) or peak loading (−13.91±4.63∞ vs. −13.24±6.15∞, p=>.05, ES =0.12), nor did it decrease the amount of eversion during loading response (6.88±2.63∞ vs. 7.21±1.99∞, p=>.05, ES =0.14). No difference in eversion angular velocity was identified between barefoot and shod running (−175.46±100.52∞/s vs. −151.73±70.73∞/s, p=>.05, ES =0.27). Conclusion: In this study, footwear didnot changehindfoot eversion at initial contact or peak loading, nor significantly reduce the amount of eversion or the peak eversion velocity occurring during loading. These results suggest hindfoot kinematicswere not altered by the shoe used in this study. We found no evidence that design features in the heel (i.e. heel counter) providemotion control benefits (i.e. decrease hindfoot eversion) to the foot during stance phase of running. It is possible that the purported feature of running shoe heel counters of ‘motion control’ with reference to the hindfoot require re-evaluation.

The influence of iliotibial band syndrome history on running biomechanics examined via principal components analysis

Iliotibial band syndrome (ITBS) is a common knee overuse injury among female runners. Atypical discrete trunk and lower extremity biomechanics during running may be associated with the etiology of ITBS. Examining discrete data points limits the interpretation of a waveform to a single value. Characterizing entire kinematic and kinetic waveforms may provide additional insight into biomechanical factors associated with ITBS. Therefore, the purpose of this cross-sectional investigation was to determine whether female runners with previous ITBS exhibited differences in kinematics and kinetics compared to controls using a principal components analysis (PCA) approach. Forty participants comprised two groups: previous ITBS and controls. Principal component scores were retained for the first three principal components and were analyzed using independent t-tests. The retained principal components accounted for 93–99% of the total variance within each waveform. Runners with previous ITBS exhibited low principal component one scores for frontal plane hip angle. Principal component one accounted for the overall magnitude in hip adduction which indicated that runners with previous ITBS assumed less hip adduction throughout stance. No differences in the remaining retained principal component scores for the waveforms were detected among groups. A smaller hip adduction angle throughout the stance phase of running may be a compensatory strategy to limit iliotibial band strain. This running strategy may have persisted after ITBS symptoms subsided.

Association of Navicular Drop and Selected Lower-Limb Biomechanical Measures During the Stance Phase of Running

There is evidence to suggest that navicular drop measures are associated with specific lower-extremity gait biomechanical parameters. The aim of this study was to examine the relationship between navicular drop and a) rearfoot eversion excursion, b) tibial internal rotation excursion, c) peak ankle inversion moment, and d) peak knee adduction moment during the stance phase of running. Sixteen able-bodied men having an average age of 28.1 (SD=5.30) years, weight of 81.5 (SD=10.40) kg, height of 179.1 (SD=5.42) cm volunteered and ran barefoot at 170 steps/minute over a force plate. Navicular drop measures were negatively correlated with tibial internal rotation excursion (r=-0.53, P=.01) but not with rearfoot eversion excursion (r=-0.19; P=.23). Significant positive correlations were found between navicular drop and peak knee adduction moment (r=.62, P<.01) and peak ankle inversion moment (r=.60, P<.01). These findings suggest that a low navicular drop measure could be associated with increasing tibial rotation excursion while high navicular drop measure could be associated with increased peak ankle and knee joint moments. These findings indicate that measures of navicular drop explained between 28% and 38% of the variability for measures of tibial internal rotation excursion, peak knee adduction moment and peak ankle inversion moments.

EFFECTS OF STRIKING STRATEGY ON LOWER EXTREMITY LOADING DURING RUNNING

BackroundIt is expected that every second runner has a running-related overuse injury each year. The knee joint and Achilles tendon are the most commonly injured sites covering both about one...

Relationship between Hip Strength and Trunk Motion in College Cross-Country Runners

Hip strength may directly relate to abnormal running mechanics and contribute to the high incidence of overuse injuries in distance runners. The purpose of this study was to determine the relationship between hip isokinetic strength and thorax and pelvic motion during treadmill running. Isokinetic hip strength and treadmill running kinematics were collected on 24 collegiate cross-country runners (14 males and 10 females). Each subject completed a running protocol on a treadmill at a self-selected speed (3.58 ± 0.26 m·s) and prescribed speed (3.58 ± 0.0 m·s). Kinematic data were collected with retroreflective markers attached to the thorax, pelvis, and each lower extremity segment (thigh, shank, and foot). Thorax and pelvis range of motion (ROM) were calculated from initial ground contact to toe-off. Pearson correlation coefficients were used to determine the relationship between strength and ROM (P < 0.05). Differences between male and female athletes were tested with mixed-design ANOVAs (P < 0.05). Isokinetic hip extension and abduction torque had significant inverse correlations to thorax axial rotation ROM during stance phase of running (r = -0.60 and r = -0.53) at self-selected speed. Frontal plane pelvic obliquity ROM was also significantly correlated to hip strength (extension r = -0.49; abduction r = -0.44). Similar correlations were found during the prescribed speed condition. Female runners had significantly decreased normalized strength (hip extension 1.8 ± 0.4 N·m·kg, P < 0.05; hip abduction 1.0 ± 0.2 N·m·kg, P < 0.05), increased pelvic obliquity (13.1° ± 2.6°, P < 0.05), and thorax axial rotation (34.5° ± 7.0°, P < 0.05) ROM compared to males (hip extension 2.5 ± 0.5 N·m·kg; hip abduction 1.3 ± 0.2 N·m·kg; pelvic obliquity 8.9° ± 1.9°; thorax axial rotation 22.6° ± 3.5°). Moderate correlations were found in hip extensor and hip abductor strength and pelvic and thorax motion during running in collegiate runners.

Exercise-induced changes in triceps surae tendon stiffness and muscle strength affect running economy in humans

The purpose of the present study was to investigate whether increased tendon-aponeurosis stiffness and contractile strength of the triceps surae (TS) muscle-tendon units induced by resistance training would affect running economy. Therefore, an exercise group (EG, n = 13) performed a 14-week exercise program, while the control group (CG, n = 13) did not change their training. Maximum isometric voluntary contractile strength and TS tendon-aponeurosis stiffness, running kinematics and fascicle length of the gastrocnemius medialis (GM) muscle during running were analyzed. Furthermore, running economy was determined by measuring the rate of oxygen consumption at two running velocities (3.0, 3.5 ms(-1)). The intervention resulted in a ∼7 % increase in maximum plantarflexion muscle strength and a ∼16 % increase in TS tendon-aponeurosis stiffness. The EG showed a significant ∼4 % reduction in the rate of oxygen consumption and energy cost, indicating a significant increase in running economy, while the CG showed no changes. Neither kinematics nor fascicle length and elongation of the series-elastic element (SEE) during running were affected by the intervention. The unaffected SEE elongation of the GM during the stance phase of running, in spite of a higher tendon-aponeurosis stiffness, is indicative of greater energy storage and return and a redistribution of muscular output within the lower extremities while running after the intervention, which might explain the improved running economy.

Tibiofemoral kinematics: the effect of footwear and foot orthoses during running

Background The knee is the most common site of running related injuries (42.1% of all injuries). Orthoses are thought to manage knee pain by reducing internal tibial rotation as the subtalar joint pronates. However, the influence of the footwear that orthoses are placed in is often ignored. This study aimed to determine the immediate effects of footwear and foot orthoses on transverse plane rotation of the tibiofemoral joint during the stance phase of running.

In Vivo Analysis of the Isolated Posterior Cruciate Ligament–Deficient Knee During Functional Activities

Background: Most patients with isolated posterior cruciate ligament (PCL) injuries have minimal symptoms, and nonoperative treatment is recommended. However, over time, these patients can develop significant degenerative changes in their knees. Historically, PCL laxity is graded by nonweightbearing anteroposterior measuring techniques that do not reproduce the true, dynamic weightbearing conditions in the injured knee. The purpose of this study was to determine the patholaxity in patients with isolated PCL deficiency during functional weightbearing activities (running, walking, and stair ascent). Hypothesis: Patients with unilateral, isolated PCL deficiency will demonstrate dynamic anteroposterior and rotational instability in their affected knees during functional activities of level running and stair ascent compared with their unaffected, contralateral knees. Study Design: Controlled laboratory study. Methods: Nine asymptomatic patients with isolated grade II PCL injury underwent Dynamic Stereo X-Ray (DSX) of both knees during level running and stair ascent. Three-dimensional reconstructions of the patients’ bilateral distal femurs and proximal tibias were created from high-resolution computed tomography (CT) scans. Three-dimensional joint kinematics were determined using a model-based tracking approach to align the radiographic images with CT-derived bone models. The resulting tibiofemoral rotations and translations for the PCL-deficient and PCL-intact knees were then compared. Results: During level running, the tibia of the PCL-deficient knee was approximately 2 mm posteriorly subluxated and had an anterior velocity relative to the femur approximately 40 mm/s greater than the contralateral, uninjured knee; however, this was only during the swing phase. No significant differences were found during the stance phase of running. During stair ascent, the tibia of the PCL-deficient knee was approximately 4 mm posteriorly subluxated compared with the intact limb during the terminal swing phase and early stance phase. Between foot strike and the time of peak ground-reaction force (GRF), the tibia of the PCL-deficient knee translated anteriorly relative to the femur with velocities 3 to 4 times greater than in the intact limb. Level walking was also evaluated in 3 patients, but no differences were seen, and it was not tested in the remaining 6 patients. Conclusion: Changes in knee kinematics due to isolated PCL injuries were highly activity dependent. During running, small differences were identified only during the swing phase when the knee was unloaded. However, during stair ascent, significant differences extended from the late swing into early stance phase. During the swing phase of stair ascent, the tibia in the PCL-deficient joint subluxated posteriorly. Then, as load was transferred to the ascending limb, the tibia reduced anteriorly with high velocity relative to the femur. The resulting shear motion may expose the loaded joint to abnormal and potentially damaging forces. Clinical Relevance: During functional activities, patients with isolated PCL injuries experience significant knee instability that cannot be identified by standard nonweightbearing static laxity measurements. The finding that different activities create different degrees of instability may have important implications for rehabilitation and activity limitations for PCL-deficient individuals.

Differential segmental strain during active lengthening in a large biarticular thigh muscle during running

The iliotibialis lateralis pars postacetabularis (ILPO) is the largest muscle in the hindlimb of the guinea fowl and is thought to play an important role during the stance phase of running, both absorbing and producing work. Using sonomicrometry and electromyography, we examined whether the ILPO experiences differential strain between proximal, central and distal portions of the posterior fascicles. When the ILPO is being lengthened while active, the distal portion was found to lengthen significantly more than either the proximal or central portions of the muscle. Our data support the hypothesis that the distal segment lengthened farther and faster because it began activity at shorter sarcomere lengths on the ascending limb of the length-tension curve. Probably because of the self-stabilizing effects of operating on the ascending limb of the length-tension curve, all segments reached the end of lengthening and started shortening at the same sarcomere length. During shortening, this similarity in sarcomere length among the segments was maintained, as predicted from force-velocity effects, and shortening strain was similar in all segments. The differential active strain during active lengthening is thus ultimately determined by differences in strain during the passive portion of the cycle. The sarcomere lengths of all segments of the fascicles were similar at the end of active shortening, but after the passive portion of the cycle the distal segment was shorter. Differential strain in the segments during the passive portion of the cycle may be caused by differential joint excursions at the knee and hip acting on the ends of the muscle and being transmitted differentially by the passive visco-elastic properties of the muscle. Alternatively, the differential passive strain could be due to the action of active or passive muscles in the thigh that transmit force to the IPLO in shear. Based on basic sarcomere dynamics we predict that differential strain is more likely to occur in muscles undergoing active lengthening at the beginning of contraction than those undergoing only shortening.

The effects of a 30-min run on the mechanics of the human Achilles tendon

Tendinous structures often exhibit reduced stiffness following repeated loading via static muscular contractions. The purpose of this study was to determine if human Achilles tendon (AT) stiffness is affected by the repeated loading experienced during running and if this affects normal muscle-tendon interaction. Twelve male participants (mean ± SD: age 27 ± 5 years, height 1.79 ± 0.06 m, mass 78.6 ± 8.4 kg) completed a 30 min run at 12 kmph on a treadmill. AT properties were determined before and after the run during a series of one-legged hops. During hopping and running, AT length data were acquired from a combination of ultrasound imaging (50 Hz) and kinematic data (200 Hz). AT force was estimated from inverse dynamics during hopping and AT stiffness was computed from plots of AT force and length. AT stiffness was not significantly different post run (pre 163 ± 41 N mm(-1), post 147 ± 52 N mm(-1), P > 0.05) and peak AT strain during the stance phase of running (calculated relative to AT length during standing) was similar at different time points during the run (3.5 ± 1.8% at 1 min, 3.2 ± 1.8% at 15 min and 3.8 ± 2% at 30 min). It was concluded that the loading experienced during a single bout of running does not affect the stiffness of the AT and that the properties of the AT are stable during locomotion. This may have implications for muscle fascicle behaviour and Achilles tendon injury mechanisms.

The effect of gluteus medius training on hip kinematics in a runner with iliotibial band syndrome

Iliotibial band syndrome (ITBS) is a common clinical presentation in runners. There are several hypotheses to explain this condition including faulty control of the hip joint in the frontal plane during the stance phase of running. It is postulated that improving activity in the gluteus medius muscle may assist in produc-ing more appropriate stabilization and therefore reduce the stress on the Iliotibial band (ITB). This single case study provides an interesting clinical scenario where a single-subject with ITBS was measured for hip kinematics during running, before and after a trial period of classic gluteus medius exercises. The biomechanical data show an initial (pre-intervention) increase in adduction position during the stance phase of running on the affected side (in contrast to the unaffected side). This was measured using a Moven motion analysis suit. After the trial intervention period, the relative position of the affected hip had reduced in adduction at both heel strike and at 30° knee flexion. This study provides support for the theory that hip control in the frontal plane may be a contributing factor in ITBS. Clinicians are encouraged to monitor hip control as well as ITBS symptoms when they utilise this gluteus medius protocol. Further research to establish whether change in pelvic control results in decrease in ITBS symptoms is warranted.

J231025 ランニング立脚前期における足関節目内負荷評価式の構築([J23102]スポーツ・アンド・ヒューマン・ダイナミクス(2))

J231025 ランニング立脚前期における足関節目内負荷評価式の構築([J23102]スポーツ・アンド・ヒューマン・ダイナミクス(2))

The natural frequency of the foot-surface cushion during the stance phase of running

Researchers have reported on the stiffness of running in holistic terms, i.e. for the structures that are undergoing deformation as a whole rather than in terms of specific locations. This study aimed to estimate both the natural frequency and the viscous damping coefficient of the human foot-surface cushion, during the period between the heel strike and the mid-stance phase of running, using a purposely developed one degree-of-freedom inverted pendulum state space model of the leg. The model, which was validated via a comparison of measured and estimated ground reaction forces, incorporated a novel use of linearized and extended Kalman filter estimators. Investigation of the effect of variation of the natural frequency and/or the damping of the cushioning mechanism during running, using the said model, revealed the natural frequency of running on said foot-surface cushion, during the stance phase, to lie between 5 and 11Hz. The “extended Kalman filter (EKF)” approach, that was used here for the first time to directly apply measured ground forces, may be widely applicable to the identification process of combined estimation of both unknown physiological state and mechanical characteristics of the environment in an inverse dynamic model.

A Proximal Strengthening Program Improves Pain, Function, and Biomechanics in Women With Patellofemoral Pain Syndrome

Background: It is hypothesized that patients with patellofemoral pain syndrome (PFPS) have hip and core muscle weakness leading to dynamic malalignment of the lower extremity. Thus, hip strengthening is a common PFPS treatment approach. Purpose: To determine changes in hip strength, core endurance, lower extremity biomechanics, and patient outcomes after proximally focused rehabilitation for PFPS patients. Study Design: Case series; Level of evidence, 4. Methods: Nineteen women (age, 22.68 ± 7.19 years; height, 1.64 ± 0.07 m; mass, 60.2 ± 7.35 kg) with PFPS participated in an 8-week program to strengthen the hip and core muscles and improve dynamic malalignment. Paired t tests were used to compare the dependent variables between prerehabilitation and postrehabilitation. The dependent variables were pain; functional ability; isometric hip abduction and external rotation strength; anterior, lateral, and posterior core endurance; joint range of motion (ROM; rearfoot eversion, knee abduction and internal rotation, and hip adduction and internal rotation); and peak internal joint moments (rearfoot inversion, knee abduction, and hip abduction and external rotation) during the stance phase of running. Results: Significant improvements in pain, functional ability, lateral core endurance, hip abduction, and hip external rotation strength were observed. There was also a significant reduction in the knee abduction moment during running, although there were no significant changes in joint ROM. Conclusion: An 8-week rehabilitation program focusing on strengthening and improving neuromuscular control of the hip and core musculature produces positive patient outcomes, improves hip and core muscle strength, and reduces the knee abduction moment, which is associated with developing PFPS.

Muscle forces during running predicted by gradient-based and random search static optimisation algorithms

Muscle forces during locomotion are often predicted using static optimisation and SQP. SQP has been criticised for over-estimating force magnitudes and under-estimating co-contraction. These problems may be related to SQP's difficulty in locating the global minimum to complex optimisation problems. Algorithms designed to locate the global minimum may be useful in addressing these problems. Muscle forces for 18 flexors and extensors of the lower extremity were predicted for 10 subjects during the stance phase of running. Static optimisation using SQP and two random search (RS) algorithms (a genetic algorithm and simulated annealing) estimated muscle forces by minimising the sum of cubed muscle stresses. The RS algorithms predicted smaller peak forces (42% smaller on average) and smaller muscle impulses (46% smaller on average) than SQP, and located solutions with smaller cost function scores. Results suggest that RS may be a more effective tool than SQP for minimising the sum of cubed muscle stresses in static optimisation.

Comparison of three-dimensional lower extremity running kinematics of young adult and elderly runners

The objective of this study was to compare the three-dimensional lower extremity running kinematics of young adult runners and elderly runners. Seventeen elderly adults (age 67–73 years) and 17 young adults (age 26–36 years) ran at 3.1 m · s−1 on a treadmill while the movements of the lower extremity during the stance phase were recorded at 120 Hz using three-dimensional video. The three-dimensional kinematics of the lower limb segments and of the ankle and knee joints were determined, and selected variables were calculated to describe the movement. Our results suggest that elderly runners have a different movement pattern of the lower extremity from that of young adults during the stance phase of running. Compared with the young adults, the elderly runners had a substantial decrease in stride length (1.97 vs. 2.23 m; P = 0.01), an increase in stride frequency (1.58 vs. 1.37 Hz; P = 0.002), less knee flexion/extension range of motion (26 vs. 33°; P = 0.002), less tibial internal/external rotation range of motion (9 vs. 12°; P < 0.001), larger external rotation angle of the foot segment (toe-out angle) at the heel strike (−5.8 vs. −1.0°; P = 0.009), and greater asynchronies between the ankle and knee movements during running. These results may help to explain why elderly individuals could be more susceptible to running-related injuries.

Effect of foot orthoses on magnitude and timing of rearfoot and tibial motions, ground reaction force and knee moment during running

Changes in magnitude and timing of rearfoot eversion and tibial internal rotation by foot orthoses and their contributions to vertical ground reaction force and knee joint moments are not well understood. The objectives of this study were to test if orthoses modify the magnitude and time to peak rearfoot eversion, tibial internal rotation, active ground reaction force and knee adduction moment and determine if rearfoot eversion, tibial internal rotation magnitudes are correlated to peak active ground reaction force and knee adduction moment during the first 60% stance phase of running. Eleven healthy men ran at 170 steps per minute in shod and with foot orthoses conditions. Video and force-plate data were collected simultaneously to calculate foot joint angular displacement, ground reaction forces and knee adduction moments. Results showed that wearing semi-rigid foot orthoses significantly reduced rearfoot eversion 40% (4.1°; p = 0.001) and peak active ground reaction force 6% (0.96 N/kg; p = 0.008). No significant time differences occurred among the peak rearfoot eversion, tibial internal rotation and peak active ground reaction force in both conditions. A positive and significant correlation was observed between peak knee adduction moment and the magnitude of rearfoot eversion during shod ( r = 0.59; p = 0.04) and shod/orthoses running ( r = 0.65; p = 0.02). In conclusion, foot orthoses could reduce rearfoot eversion so that this can be associated with a reduction of knee adduction moment during the first 60% stance phase of running. Finding implies that modifying rearfoot and tibial motions during running could not be related to a reduction of the ground reaction force.