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Context: Prophylactic knee bracing is extensively utilized in athletic populations to reduce the high risk from knee injuries, but its role in the attenuation of anterior cruciate ligament (ACL) pathologies is not well understood. Objective: The aim of this investigation was to explore the effects of a prophylactic knee sleeve on ACL loading parameters linked to the etiology of injury in recreational athletes. Setting: Laboratory. Design: Repeated measures. Participants: Thirteen healthy male recreational athletes. Intervention: Participants performed run, cut, and single-leg hop movements under 2 conditions; prophylactic knee sleeve and no sleeve. Main Outcome Measures: Biomechanical data were captured using an 8-camera 3D motion capture system and a force platform. Peak ACL force, average ACL load rate, and instantaneous ACL load rate were quantified using a musculoskeletal modeling approach. Results: The results showed that both average and instantaneous ACL load rates were significantly reduced when wearing the knee sleeve in the hop (sleeve = 612.45/1286.39 N/kg/s and no sleeve = 743.91/1471.42 N/kg/s) and cut (sleeve = 222.55/1058.02 N/kg/s and no sleeve = 377.38/1183.01 N/kg/s) movements. Conclusions: Given the biomechanical association between ACL loading and the etiology of ACL injuries, it is proposed that athletes may be able to attenuate their risk from injury during cut and hop movements through utilization of a prophylactic knee sleeve. [ABSTRACT FROM AUTHOR]

In running analyses where both kinetic and kinematic information is recorded, participants are required to make foot contact with a force and/or pressure measuring transducer. Problems arise if participants modify their gait patterns to ensure contact with the device. There is currently a paucity of research investigating the influence of different underfoot kinetic measuring devices on 3-dimensional kinematics of running. Fifteen participants ran at 4.0 m/s in four different conditions: over a floor embedded force plate, Footscan, Matscan, and with no device. Three-dimensional angular kinematic parameters were collected using an eight camera motion analysis system. Hip, knee, and ankle joint kinematics were contrasted using repeated-measures ANOVAs. Participants also rated their subjective comfort in striking each of the three force measuring devices. Significant differences from the uninhibited condition were observed using the Footscan and Matscan in all three planes of rotation, whereas participants subjectively rated the force plate significantly more comfortable than either the Footscan/ Matscan devices. The findings of the current investigation therefore suggest that the disguised floor embedded force plate offers the most natural running condition. It is recommended that analyses using devices such as the Footscan/Matscan mats overlying the laboratory surface during running should be interpreted with caution. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of sports surface on the magnitude of impact shock experienced during a lunge movement. Thirteen experienced, competitive fencers (age 32.4 ± 4.6 years; height 178.4 ± 7.2 cm; mass 74.4 ± 9.1 kg) performed 10 lunges on four different surfaces: concrete with an overlaid vinyl layer (COVL), wooden sprung court surface (WSCS), metallic carpet fencing piste overlaid on the WSCS, and aluminum fencing piste overlaid on the WSCS. An accelerometer measured accelerations along the longitudinal axis of the tibia at 1000 Hz. The results identified a significantly (P < .05) larger impact shock magnitude was experienced during a lunge on the COVL (14.88 ± 8.45 g) compared with the WSCS (11.61 ± 7.30 g), WSCS with metallic carpet piste (11.14 ± 6.38 g) and WSCS with aluminum piste (11.95 ± 7.21 g). Furthermore, the two types of piste used had no significant effect the impact shock magnitude measured when overlaid on the WSCS compared with the WSCS on its own. The results of this investigation suggest that occurrences of injuries related to increased levels of impact shock may be reduced through the utilization of a WSCS as opposed to a COVL surface during fencing participation. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to explore the effects of barefoot and minimally shod footwear on effective mass and determine the implications that this had for transient loading during running. Fifteen male runners ran at 4.0 m/s in five different footwear conditions (barefoot, running trainer, Nike-free, Inov-8 and Vibram five-fingers). Kinematics were collected using an 8 camera motion capture system and ground reaction forces (GRF) via an embedded force platform. Effective mass was examined using impulsemomentum modelling. Differences between types of footwear were examined using one-way repeated measures ANOVA and linear regression was used to determine the association between effective mass and instantaneous loading rate. The findings showed that effective mass was significantly larger in the barefoot (11.47%BW), Nike-free (9.81%BW), Inov-8 (12.10%BW) and Vibram five-fingers (8.84%BW) compared to the running trainer (6.86%BW). Furthermore, instantaneous loading rate was significantly larger in the barefoot (347.55 BW/s), Nike-free (178.76 BW/s), Inov-8 (369.93 BW/s) and Vibram five-fingers (339.37 BW/s) compared to the running trainer (133.18 BW/s). It was also revealed that there were significant positive associations between effective mass and the instantaneous rate for each footwear: barefoot (R²=0.60), Nikefree (R²=0.53), Inov-8 (R²=0.80), Vibram five-fingers (R²=0.52) and running trainer (R²=0.40). The findings from the current investigation indicate that effective mass has key implications for the generation of transient forces and also that running barefoot and in minimally shod footwear may place runners at increased risk from impact-related injuries compared to the traditional running shoes. [ABSTRACT FROM AUTHOR]

Asymmetry in forelimb dorsal hoof wall angles, termed unevenness, is associated with forelimb gait asymmetries, but compensatory mechanisms and out of plane ground reaction forces (GRFs) due to unevenness have yet to be documented. The aim of this study was therefore to investigate the effects of fore hoof unevenness on contralateral fore and hind limb force vectors patterns, in both sagittal and frontal planes. A group of n = 34 riding horses were classified into four groups: hoof angle difference of more than 1.5 degrees (UNEVEN; n = 27), including higher left fore (HIGH-LF; n = 12), higher right fore (HIGH-RF; n = 15), and hoof angle difference of less than 1.5 degrees (EVEN; n = 7). Three dimensional ground reaction forces GRFs were collected during trotting. GRF summary vectors representing the magnitude (VecMag) and angular direction (VecAng) of the entire stance phase in the sagittal and the frontal plane were calculated. The effects of unevenness on GRF production were explored using linear regression, repeated measures ANOVA and statistical parametric mapping (SPM) with significance at (P<0.05). In all uneven groups, increasing unevenness affected sagittal VecAng values in the forelimbs, with more propulsive GRF in the high hoof. In the HIGH-RF group, medial GRFs were also found in the high RF hoof compared to lateral GRFs in the low LF hoof (RF VecAng: 0.97±1.64 (deg); LF VecAng: -0.64±1.19 (deg); P<0.05). In both HIGH groups, compensatory associations to increasing unevenness were only found in the RH, but also a significantly greater lateral VecAng was found in the LH (P<0.05) compared to the RH limb. No significant differences (P>0.05) were found between hindlimb pairs in the EVEN group. Unbalanced sagittal and increased frontal plane GRFs in uneven horses suggest that they have greater locomotory challenges, as the equine musculoskeletal system is not constructed to withstand movement and loading in the frontal plane as effectively as it is in the sagittal plane. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the effects of prophylactic knee bracing on patellar tendon loading parameters.Methods: Twenty recreational athletes (10 male and 10 female) from different athletic disciplines performed run, cut and single leg hop movements under two conditions (prophylactic knee brace/no-brace). Lower extremity kinetics and kinematics were examined using a piezoelectric force plate and three-dimensional motion capture system. Patellar tendon loading was explored using a mathematical modelling approach, which accounted for co-contraction of the knee flexors. Tendon loading parameters were examined using 2 (brace) × 3 (movement) × 2 (sex) mixed ANOVAs.Results: Tendon instantaneous load rate was significantly reduced in female athletes in the run (brace 289.14 BW/s no-brace 370.06 BW/s) and cut (brace 353.17 BW/s/no-brace 422.01 BW/s) conditions whilst wearing the brace.Conclusions: Female athletes may be able to attenuate their risk from patellar tendinopathy during athletic movements, through utilization of knee bracing, although further prospective research into the prophylactic effects of knee bracing is required before this can be clinically substantiated. [ABSTRACT FROM AUTHOR]

The aim of the current investigation was to examine the effects of high- and low-cut basketball-specific footwear, in relation to minimalist and conventional athletic footwear, on the kinetics and three-dimensional (3D) kinematics of sport-specific basketball movements. Ten males performed run and 45 cut movements, whilst wearing low-cut, high-cut, minimalist and conventional athletic footwear. 3D kinematics of the lower extremities were measured using an eight-camera motion analysis system, alongside the vertical rate of loading, which was obtained using an embedded force platform. Footwear differences in 3D kinematic and loading rate parameters were examined using 4 (footwear) (movement), repeated measures ANOVA. The results showed that loading rate was significantly larger in the minimalist footwear ( and BW/s), in relation to the low-cut ( and BW/s), high-cut ( and BW/s) and conventional ( and BW/s) conditions. In addition, it was also revealed during the run movement that peak angles of eversion were reduced significantly when wearing the high-cut () footwear, compared to the low-cut , minimalist and conventional conditions. The findings from the current investigation indicate that from an injury prevention context, conventional athletic footwear may be most appropriate for basketball players who are susceptible to chronic impact-related injuries, and high-cut footwear may be most suitable for players who require additional medial/lateral ankle stability. [ABSTRACT FROM AUTHOR]

Purpose. The current investigation aimed to examine the effects of running barefoot and in conventional and barefoot inspired footwear on the loads borne by the tibiofemoral joint. Methods. Fifteen male participants ran at 4.0 m/s over a force platform whilst running barefoot, in barefoot inspired footwear and also in conventional footwear. Lower body kinematics were collected using an eight-camera motion capture system. Peak tibiofemoral force, peak tibiofemoral stress, and tibiofemoral load rate were extracted and compared between footwear via one-way repeated measures ANOVA. Results. The results showed that the tibiofemoral instantaneous load rate was significantly lower in conventional footwear (106.63 BW/s) in comparison with barefoot running (173.87 BW/s), Vibram Five Fingers (160.17 BW/s), Merrell (155.32 BW/s), Inov-8 (167.79 BW/s), and Nike Free (144.72 BW/s). Conclusions. This indicates that running barefoot and in barefoot inspired footwear may place runners at increased risk from running-related tibiofemoral pathologies. [ABSTRACT FROM AUTHOR]

The aim of the current investigation was to comparatively examine the effects of conventional, energy boost and spring footwear on the loads experienced by the patellofemoral joint and Achilles tendon during running. Ten male runners underwent 3D running analysis at 4.0 m/s. Patellofemoral joint and Achilles tendon loads were quantified using a musculoskeletal modelling approach and contrasted between footwear using one-way repeated measures ANOVA. The results showed that peak patellofemoral force and pressure were significantly greater in conventional (force = 31.72 N/kg & pressure = 10.05 MPa) footwear in relation to energy boost (27.80 N/kg & pressure = 9.02 MPa). In addition peak Achilles tendon force was shown to be significantly greater in conventional (54.98 N/kg) compared to springblade (49.92 N/kg) footwear. On the basis that peak patellofemoral and Achilles tendon forces were significantly greater when running in conventional footwear, the findings from the current investigation indicate that utilization of conventional running footwear may place runners at increased risk from knee and ankle pathologies in comparison to energy boost and springblade shoe conditions. [ABSTRACT FROM AUTHOR]

Purpose. The aim of the current study was to comparatively examine the effects of energy return, spring and conventional footwear on the kinetics and kinematics of running. Methods. Twelve male runners ran over an embedded force platform at 4.0 m · s-1 in the three footwear conditions. Lower limb kinematics were collected using an 8 camera motion capture system and tibial accelerations were obtained using an accelerometer. Differences in kinetic and kinematic parameters between footwear were examined using one-way repeated measures ANOVA. Results. The results showed that there were no significant differences in kinetic parameters between footwear. However, it was shown that that spring footwear were associated with significantly greater angles of peak eversion (-12.49°) and tibial internal rotation (13.09°) in comparison to the conventional footwear (eversion = -10.52° & tibial internal rotation = 10.84°). Conclusions. Therefore, the findings from the current investigation indicate that spring footwear may place runners at increased risk from chronic injury related to excessive ankle eversion/tibial internal rotation. [ABSTRACT FROM AUTHOR]

Minimalist footwear has been the subject of much attention in footwear research. More recently, maximalist footwear, which feature an oversized midsole have been developed. The aim of the current investigation was to compare the kinetics and kinematics of running in minimalist, maximalist and conventional footwear. Twelve male runners ran over an embedded force platform at 4.0 m s−1in the three footwear conditions. Lower limb kinematics were collected using an eight-camera motion capture system, and tibial accelerations were obtained using an accelerometer. Differences in kinetics and kinematics between footwear were examined using one-way repeated measures ANOVA. The results showed that both instantaneous loading rate and peak tibial acceleration were significantly larger in the minimalist (305.58 BW/s and 9.54 g) compared to the maximalist (141.67 BW/s and 7.99 g) and conventional (127.30 BW/s and 6.73 g) footwear. In addition, peak tibial internal rotation was significantly larger in the minimalist (9.64°) compared to conventional (6.88°) footwear. These findings indicate that minimalist footwear may place runners at increased risk from chronic injury. Further work is, nonetheless, required using runners who habitually utilize these footwear before these findings can be truly substantiated. [ABSTRACT FROM AUTHOR]

The barbell back squat is commonly used by athletes participating in resistance training. The barbell squat is typically performed using standard athletic shoes, or specially designed weightlifting footwear, although there are now a large number of athletes who prefer to squat barefoot or in barefoot-inspired footwear. This study aimed to determine how these footwear influence 3-D kinematics and muscle activation potentials during the barbell back squat. Fourteen experienced male participants completed squats at 70% 1 rep max in each footwear condition. 3-D kinematics from the torso, hip, knee and ankle were measured using an eight-camera motion analysis system. In addition, electromyographical (EMG) measurements were obtained from the rectus femoris, tibialis anterior, gastrocnemius, erector spinae and biceps femoris muscles. EMG parameters and joint kinematics were compared between footwear using repeated-measures analyses of variance. Participants were also asked to subjectively rate which footwear they preferred when performing their squat lifts; this was examined a chi-squared test. The kinematic analysis indicated that, in comparison to barefoot the running shoe was associated with increased squat depth, knee flexion and rectus femoris activation. The chi-squared test was significant and showed that participants preferred to squat barefoot. This study supports anecdotal evidence of athletes who prefer to train barefoot or in barefoot-inspired footwear although no biomechanical evidence was found to support this notion. [ABSTRACT FROM AUTHOR]

Purpose. There has yet to be a combined analysis of three-dimensional multi-segment foot kinematics and plantar fascia strain in running gait at various degrees of inclination. The aim of the current study was therefore to investigate the above during treadmill running at different inclines (0°, 5°, 10° and 15°). Methods. Twelve male participants ran at 4.0 m · s-1 in the four different inclinations. Three-dimensional kinematics of the foot segments and plantar fascia strain were quantified for each incline and contrasted using one-way repeated measures ANOVA. Results and conclusions. The results showed that plantar fascia strain increased significantly as a function of running incline. Given the projected association between plantar fascia strain and the aetiology of injury, inclined running may be associated with a greater incidence of injury to the plantar fascia. [ABSTRACT FROM AUTHOR]

Purpose. Cycling has been shown to be associated with a high incidence of chronic pathologies. Foot orthoses are frequently used by cyclists in order to reduce the incidence of chronic injuries. The aim of the current investigation was to examine the influence of different varus orthotic inclines on the three-dimensional kinematics of the lower extremities during the pedal cycle. Methods. Kinematic information was obtained from ten male cyclists using an eight-camera optoelectronic 3-D motion capture system operating at 250 Hz. Participants cycled with and without orthotic intervention at three different cadences (70, 90 and 110 RPM). The orthotic device was adjustable and four different wedge conditions (0 mm - no orthotic, 1.5 mm, 3.0 mm and 4.5 mm) were examined. Two-way repeated measures ANOVAs were used to compare the kinematic parameters obtained as a function of orthotic inclination and cadence. Participants were also asked to subjectively rate their comfort in cycling using each of the four orthotic devices on a 10-point Likert scale. Results. The kinematic analysis indicated that the orthotic device had no significant influence at any of the three cadences. Analysis of subjective preferences showed a clear preference for the 0 mm, no orthotic, condition. Conclusions. This study suggests that foot orthoses do not provide any protection from skeletal malalignment issues associated with the aetiology of chronic cycling injuries. [ABSTRACT FROM AUTHOR]

Carbohydrate (CHO) mouth rinse has been shown to improve time trial performance. Although the exact mechanism remains un-established, research postulates that there are oral cavity receptors which increase neural drive. Increasing the duration of the mouth rinse could potentially increase stimulation of these receptors. The aim of the current investigation was to determine whether the duration of mouth rinse with 6.4% CHO affected 30-min self-selected cycling performance. Eleven male participants (age =24.1±3.9 years) performed three 30-min self-paced trials. On one occasion water was given as a mouth rinse for 5 s without being ingested placebo (PLA), on the other two occasions a 6.4% CHO solution was given for 5 and 10 s. Distance cycled, heart rate, ratings of perceived exertion, cadence, speed and power were recorded throughout all trials. The main findings were that distance cycled during the 10-s mouth rinse trial (20.4±2.3 km) was significantly greater compared to the PLA trial (19.2±2.2 km;P<0.01). There was no difference between the 5- and 10-s trials (P=0.15). However, 10 out of 11 participants cycled further during the 5-s trial compared to PLA, and eight cycled further during the 10-s trial compared to the 5 s. In conclusion, although there was an improvement in distance cycled with the 5-s mouth rinse compared to the PLA it was only significant with 10 s suggesting a dose response to the duration of mouth rinse. [ABSTRACT FROM PUBLISHER]

Background:Barefoot running has been the subject of much attention in footwear biomechanics literature, based on the supposition that it serves to reduce the occurrence of overuse injuries in comparison to conventional shoe models. This consensus has led footwear manufacturers to develop shoes that aim to mimic the mechanics of barefoot locomotion. Objectives:This study compared the impact kinetics and three-dimensional (3-D) joint angular kinematics observed while running barefoot, in conventional cushioned running shoes and in shoes designed to integrate the perceived benefits of barefoot locomotion. The aim of the current investigation was therefore to determine whether differences in impact kinetics exist between the footwear conditions and whether shoes that aim to simulate barefoot movement patterns can closely mimic the 3-D kinematics of barefoot running. Method:Twelve participants ran at 4.0 m s−1(±5%) in each footwear condition. Angular joint kinematics from the hip, knee and ankle in the sagittal, coronal and transverse planes were measured using an eight-camera motion analysis system. In addition, simultaneous tibial acceleration and ground reaction forces were obtained. Impact parameters and joint kinematics were subsequently compared using repeated-measures analyses of variance (ANOVAs). Results:The kinematic analysis indicated that, in comparison to the conventional and barefoot-inspired shoes, running barefoot was associated with significantly greater plantar–flexion at footstrike and range of motion to peak dorsiflexion. Furthermore, the kinetic analysis revealed that, compared to the conventional footwear, impact parameters were significantly greater in the barefoot condition. Conclusions:This study suggests that barefoot running is associated with impact kinetics linked to an increased risk of overuse injury when compared to conventional shod running. Furthermore, the mechanics of the shoes that aim to simulate barefoot movement patterns do not seem to closely mimic the kinematics of barefoot locomotion. [ABSTRACT FROM AUTHOR]