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1.
This study aimed to investigate the activation of lower limb muscles during barefoot and shod running with forefoot or rearfoot footfall patterns. Nine habitually shod runners were asked to run straight for 20 m at self-selected speed. Ground reaction forces and thigh and shank muscle surface electromyographic (EMG) were recorded. EMG outcomes (EMG intensity [iEMG], latency between muscle activation and ground reaction force, latency between muscle pairs and co-activation index between muscle pairs) were compared across condition (shod and barefoot), running cycle epochs (pre-strike, strike, propulsion) and footfall (rearfoot and forefoot) by ANOVA. Condition affected iEMG at pre-strike epoch. Forefoot and rearfoot strike patterns induced different EMG activation time patterns affecting co-activation index for pairs of thigh and shank muscles. All these timing changes suggest that wearing shoes or not is less important for muscle activation than the way runners strike the foot on the ground. In conclusion, the guidance for changing external forces applied on lower limbs should be pointed to the question of rearfoot or forefoot footfall patterns.  相似文献   

2.
ABSTRACT

This study aimed to explore the plantar loading variables between habitual rearfoot strike (RFS) and non-rearfoot strike (NRFS) during running. 78 healthy males participated in this study (41 RFS, 37 NRFS). In-shoe pressure sensors were used to measure plantar loading while the participants were running on a 15 m indoor runway with their preferred foot strike pattern (FSP) at 12.0 ± 5% km/h. Results indicate that force and pressure parameters were much higher in the rearfoot and midfoot regions during RFS running and relatively greater in forefoot region during NRFS running. However, compared with NRFS running, the contact area, maximum force and force-time-integrals during RFS running on total foot were 21.44% (P < 0.001, ES = 2.29), 13.99% (P = 0.006, ES = 0.64) and 21.27% (P < 0.001, ES = 0.85) higher, respectively. Total foot peak pressure and pressure-time-integral between two FSPs were similar. Higher loads in the rearfoot region may transmit to the knee joint and result in patellofemoral joint injuries. NRFS runners’ higher loads in forefoot seem to be ralated to metatarsal stress fractures and compensatory damage to the Achilles tendon. Therefore, runners should choose proper FSPs according to their unique physical conditions.  相似文献   

3.
ABSTRACT

This study examined the effect of wearing time on comfort perception and landing biomechanics of basketball shoes with different midsole hardness. Fifteen basketball players performed drop landing and layup first step while wearing shoes of different wearing time (new, 2-, 4-, 6- and 8-week) and hardness (soft, medium and hard). Two-way ANOVA with repeated measures was performed on GRF, ankle kinematic and comfort perception variables. Increased wearing time was associated with poorer force attenuation and comfort perception during landing activities (p < 0.05). The new shoes had significantly smaller forefoot (2- and 4-week) and rearfoot peak GRF impacts (all time conditions) in drop landing and smaller rearfoot peak GRF impact (6- and 8-week) in layup; shoes with 4-week of wearing time had significantly better perceptions of forefoot cushioning, forefoot stability, rearfoot cushioning, rearfoot stability and overall comfort than the new shoes (p < 0.05). Compared with hard shoes, the soft shoes had better rearfoot cushioning but poorer forefoot cushioning (p < 0.05). Shoe hardness and wearing time would play an influential role in GRF and comfort perception, but not in ankle kinematics. Although shoe cushioning performance would decrease even after a short wearing period, the best comfort perception was found at 4-week wearing time.  相似文献   

4.
PurposeThis study examined variation in foot strike types, lower extremity kinematics, and arch height and stiffness among Tarahumara Indians from the Sierra Tarahumara, Mexico.MethodsHigh speed video was used to study the kinematics of 23 individuals, 13 who habitually wear traditional minimal running sandals (huaraches), and 10 who habitually wear modern, conventional running shoes with elevated, cushioned heels and arch support. Measurements of foot shape and arch stiffness were taken on these individuals plus an additional sample of 12 individuals.ResultsMinimally shod Tarahumara exhibit much variation with 40% primarily using midfoot strikes, 30% primarily using forefoot strikes, and 30% primarily using rearfoot strikes. In contrast, 75% of the conventionally shod Tarahumara primarily used rearfoot strikes, and 25% primarily used midfoot strikes. Individuals who used forefoot or midfoot strikes landed with significantly more plantarflexed ankles, flexed knees, and flexed hips than runners who used rearfoot strikes. Foot measurements indicate that conventionally shod Tarahumara also have significantly less stiff arches than those wearing minimal shoes.ConclusionThese data reinforce earlier studies that there is variation among foot strike patterns among minimally shod runners, but also support the hypothesis that foot stiffness and important aspects of running form, including foot strike, differ between runners who grow up using minimal versus modern, conventional footwear.  相似文献   

5.
The purpose of this study was to investigate the relationship between Achilles tendon properties and foot strike patterns in long-distance runners. Forty-one highly trained male long-distance runners participated in this study. Elongation of the Achilles tendon and aponeurosis of the medial gastrocnemius muscle were measured using ultrasonography, while the participants performed ramp isometric plantar flexion up to the voluntary maximum. The relationship between the estimated muscle force and tendon elongation during the ascending phase was fit to a linear regression, the slope of which was defined as stiffness. In addition, the cross-sectional area of the Achilles tendon was measured using ultrasonography. Foot strike patterns (forefoot, midfoot and rearfoot) during running were determined at submaximal velocity (18 km · h?1) on a treadmill. The number of each foot strike runner was 12 for the forefoot (29.3%), 12 for the midfoot (29.3%) and 17 for the rearfoot (41.5%). No significant differences were observed in the variables measured for the Achilles tendon among the three groups. These results suggested that the foot strike pattern during running did not affect the morphological or mechanical properties of the Achilles tendon in long-distance runners.  相似文献   

6.
ABSTRACT

We examined the association between footfall pattern and characteristics of lower limb muscle function and compared lower limb muscle function between forefoot and rearfoot runners. Fifteen rearfoot and 16 forefoot runners were evaluated using ultrasonography of the gastrocnemii and tibialis anterior while strike index and heel strike angle quantified footfall pattern. Higher strike index was associated with lower medial gastrocnemius echo intensity (p = 0.05), lower lateral gastrocnemius echo intensity (p = 0.04), smaller tibialis anterior pennation angle (p = 0.05), and longer lateral gastrocnemius fascicle length (p = 0.04). Larger heel strike angle was associated with smaller medial gastrocnemius cross-sectional area (p = 0.04), shorter lateral gastrocnemius fascicle length (p < 0.01), and lower plantar flexion moment (p < 0.01). Larger plantar flexion moment was associated with lesser medial gastrocnemius echo intensity (p = 0.04), lesser lateral gastrocnemius echo intensity (p = 0.03), and greater lateral gastrocnemius fascicle length (p = 0.02). A smaller plantar flexion moment, larger heel strike angle, lower tibialis anterior echo intensity, larger tibialis anterior pennation angle, and smaller lateral gastrocnemius pennation angle were observed in rearfoot compared to forefoot runners (p < 0.05). Lower limb muscle architecture is associated with footfall pattern and ankle mechanics during running.

Abbreviation: EMG: electromyographic; MG: medial gastrocnemius; LG: lateral gastrocnemius; TA: tibialis anterior; EI: echo intensity; CSA: cross-sectional area; PA: pennation angle; FL: fascicle length; FT: fat thickness  相似文献   

7.
Compared to competitive runners, recreational runners appear to be more prone to injuries, which have been associated with foot strike patterns. Surprisingly, only few studies had examined the foot strike patterns outside laboratories. Therefore, this study compared the foot strike patterns in recreational runners at outdoor tracks with previously reported data. We also investigated the relationship between foot strike pattern, speed, and footwear in this cohort. Among 434 recreational runners analysed, 89.6% of them landed with rearfoot strike (RFS). Only 6.9 and 3.5% landed with midfoot and forefoot, respectively. A significant shift towards non-RFS was observed in our cohort, when compared with previously reported data. When speed increased by 1 m/s, the odds of having forefoot strike and midfoot strike relative to RFS increased by 2.3 times and 2.6 times, respectively. Runners were 9.2 times more likely to run with a forefoot strike in minimalists compared to regular running shoes, although 70% of runners in minimalists continued to use a RFS. These findings suggest that foot strike pattern may differ across running conditions and runners should consider these factors in order to mitigate potential injury.  相似文献   

8.
Comfort has been shown to be the most desired football boot feature by players. Previous studies have shown discomfort to be related to increased plantar pressures for running shoes which, in some foot regions, has been suggested to be a causative factor in overuse injuries. This study examined the correlation between subjective comfort data and objective plantar pressure for football boots during football-specific drills. Eight male university football players were tested. Plantar pressure data were collected during four football-specific movements for each of three different football boots. The global and local peak pressures based on a nine-sectioned foot map were compared to subjective comfort measures recorded using a visual analogue scale for global discomfort and a discomfort foot map for local discomfort. A weak (rs = ?0.126) yet significant (P < 0.05) correlation was shown between the peak plantar pressure experienced and the visual analogue scale rated comfort. The model only significantly predicted (P > 0.001) the outcome for two (medial and lateral forefoot) of the nine foot regions. Subjective comfort data is therefore not a reliable measure of increased plantar pressures for any foot region. The use of plantar pressure measures is therefore needed to optimise injury prevention when designing studded footwear.  相似文献   

9.
Despite the growing interest in minimalist shoes, no studies have compared the efficacy of different types of minimalist shoe models in reproducing barefoot running patterns and in eliciting biomechanical changes that make them differ from standard cushioned running shoes. The aim of this study was to investigate the acute effects of different footwear models, marketed as “minimalist” by their manufacturer, on running biomechanics. Six running shoes marketed as barefoot/minimalist models, a standard cushioned shoe and the barefoot condition were tested. Foot–/shoe–ground pressure and three-dimensional lower limb kinematics were measured in experienced rearfoot strike runners while they were running at 3.33 m · s?1 on an instrumented treadmill. Physical and mechanical characteristics of shoes (mass, heel and forefoot sole thickness, shock absorption and flexibility) were measured with laboratory tests. There were significant changes in foot strike pattern (described by the strike index and foot contact angle) and spatio-temporal stride characteristics, whereas only some among the other selected kinematic parameters (i.e. knee angles and hip vertical displacement) changed accordingly. Different types of minimalist footwear models induced different changes. It appears that minimalist footwear with lower heel heights and minimal shock absorption is more effective in replicating barefoot running.  相似文献   

10.
This study investigated the normal and parallel ground reaction forces during downhill and uphill running in habitual forefoot strike and habitual rearfoot strike (RFS) runners. Fifteen habitual forefoot strike and 15 habitual RFS recreational male runners ran at 3 m/s ± 5% during level, uphill and downhill overground running on a ramp mounted at 6° and 9°. Results showed that forefoot strike runners had no visible impact peak in all running conditions, while the impact peaks only decreased during the uphill conditions in RFS runners. Active peaks decreased during the downhill conditions in forefoot strike runners while active loading rates increased during downhill conditions in RFS runners. Compared to the level condition, parallel braking peaks were larger during downhill conditions and parallel propulsive peaks were larger during uphill conditions. Combined with previous biomechanics studies, our findings suggest that forefoot strike running may be an effective strategy to reduce impacts, especially during downhill running. These findings may have further implications towards injury management and prevention.  相似文献   

11.
Although the biomechanical properties of the various types of running foot strike (rearfoot, midfoot, and forefoot) have been studied extensively in the laboratory, only a few studies have attempted to quantify the frequency of running foot strike variants among runners in competitive road races. We classified the left and right foot strike patterns of 936 distance runners, most of whom would be considered of recreational or sub-elite ability, at the 10 km point of a half-marathon/marathon road race. We classified 88.9% of runners at the 10 km point as rearfoot strikers, 3.4% as midfoot strikers, 1.8% as forefoot strikers, and 5.9% of runners exhibited discrete foot strike asymmetry. Rearfoot striking was more common among our sample of mostly recreational distance runners than has been previously reported for samples of faster runners. We also compared foot strike patterns of 286 individual marathon runners between the 10 km and 32 km race locations and observed increased frequency of rearfoot striking at 32 km. A large percentage of runners switched from midfoot and forefoot foot strikes at 10 km to rearfoot strikes at 32 km. The frequency of discrete foot strike asymmetry declined from the 10 km to the 32 km location. Among marathon runners, we found no significant relationship between foot strike patterns and race times.  相似文献   

12.
ABSTRACT

Running-related injuries have been associated with excessive foot pronation and high vertical loading rates. Traditional plaster-molded (TPM) foot orthoses are commonly prescribed to minimize these atypical biomechanical patterns. Recently, 3D printed (3DP) orthoses have become popular, yet the functional difference between these two types of orthoses remains unknown. Therefore, this study compared running biomechanics and perceived comfort during treadmill running in three orthotic conditions: 3DP orthoses, TPM orthoses, and a no-orthoses control condition (CON). Thirteen female asymptomatic runners with excessive foot pronation were recruited. Rearfoot eversion angle and velocity (at initial contact and peak) during stance, vertical loading rates, and perceived comfort were compared. Results showed lower peak rearfoot eversion angles during running with TPM (p=0.001, d=0.38) or 3DP orthoses (p=0.002, d=0.24) than CON. No differences were observed in other biomechanical parameters among the three conditions (p>0.05). Running with TPM (p≤0.001, d=1.74–1.82) and 3DP orthoses (p<0.003, d=1.06–1.34) resulted in better perceived comfort in “medial-lateral control” and “heel cushioning” than CON. There were no statistical differences in all parameters between TPM and 3DP orthoses. The present findings indicate improved comfort during running with TPM or 3DP orthoses, which hinted 3DP orthoses could be a viable alternative to TPM orthoses for clinical practice.  相似文献   

13.
Abstract

Although the biomechanical properties of the various types of running foot strike (rearfoot, midfoot, and forefoot) have been studied extensively in the laboratory, only a few studies have attempted to quantify the frequency of running foot strike variants among runners in competitive road races. We classified the left and right foot strike patterns of 936 distance runners, most of whom would be considered of recreational or sub-elite ability, at the 10 km point of a half-marathon/marathon road race. We classified 88.9% of runners at the 10 km point as rearfoot strikers, 3.4% as midfoot strikers, 1.8% as forefoot strikers, and 5.9% of runners exhibited discrete foot strike asymmetry. Rearfoot striking was more common among our sample of mostly recreational distance runners than has been previously reported for samples of faster runners. We also compared foot strike patterns of 286 individual marathon runners between the 10 km and 32 km race locations and observed increased frequency of rearfoot striking at 32 km. A large percentage of runners switched from midfoot and forefoot foot strikes at 10 km to rearfoot strikes at 32 km. The frequency of discrete foot strike asymmetry declined from the 10 km to the 32 km location. Among marathon runners, we found no significant relationship between foot strike patterns and race times.  相似文献   

14.
BackgroundNumerous studies about the interaction between footwear (and barefoot) and kinematic and kinetic outcomes have been published over the last few years. Recent studies however lead to the conclusion that the assumed interactions depend mainly on the subjects' experience of barefoot (BF) walking/running, the preferred running strike pattern, the speed, the hardness of the surface, the thickness of the midsole material, and the runners' level of ability. The aim of the present study was to investigate lower leg kinematics of BF running and running in minimal running shoes (MRS) to assess comparability of BF kinematics in both conditions. To systematically compare both conditions we monitored the influencing variables described above in our measurement setup. We hypothesized that running in MRS does not alter lower leg kinematics compared to BF running.MethodsThirty-seven subjects, injury-free and active in sports, ran BF on an EVA foam runway, and also ran shod wearing Nike Free 3.0 on a tartan indoor track. Lower-leg 3D kinematics was measured to quantify rearfoot and ankle movements. Skin markers were used in both shod and BF running.ResultsAll runners revealed rearfoot strike pattern when running barefoot. Differences between BF and MRS running occurred particularly during the initial stance phase of running, both in the sagittal and the frontal planes. BF running revealed a flatter foot placement, a more plantar flexed ankle joint and less inverted rearfoot at touchdown compared to MRS running.ConclusionBF running does not change the landing automatically to forefoot running, especially after a systematic exclusion of surface and other influencing factors. The Nike Free 3.0 mimics some BF features. Nevertheless, changes in design of the Nike Free should be considered in order to mimic BF movement even more closely.  相似文献   

15.
This study investigated whether male runners improve running performance, running economy, ankle plantar flexor strength, and alter running biomechanics and lower limb bone mineral density when gradually transitioning to using minimalist shoes for 100% of weekly running. The study was a planned follow-up of runners (n?=?50) who transitioned to minimalist or conventional shoes for 35% of weekly structured training in a previous 6-week randomised controlled trial. In that trial, running performance and economy improved more with minimalist shoes than conventional shoes. Runners in each group were instructed to continue running in their allocated shoe during their own preferred training programme for a further 20 weeks while increasing allocated shoe use to 100% of weekly training. At the 20-week follow-up, minimalist shoes did not affect performance (effect size: 0.19; p?=?0.218), running economy (effect size: ≤?0.24; p?≥?0.388), stride rate or length (effect size: ≤?0.12; p?≥?0.550), foot strike (effect size: ≤?0.25; p?≥?0.366), or bone mineral density (effect size: ≤?0.40; p?≥?0.319). Minimalist shoes increased plantar flexor strength more than conventional shoes when runners trained with greater mean weekly training distances (shoe*distance interaction: p?=?0.036). After greater improvements with minimalist shoes during the initial six weeks of a structured training programme, increasing minimalist shoe use from 35% to 100% over 20 weeks, when runners use their own preferred training programme, did not further improve performance, running economy or alter running biomechanics and lower limb bone mineral density. Minimalist shoes improved plantar flexor strength more than conventional shoes in runners with greater weekly training distances.  相似文献   

16.
Runners tend to shift from a rearfoot to a forefoot strike pattern when running barefoot. However, it is unclear how the first attempts at running barefoot affect habitually rearfoot shod runners. Due to the inconsistency of their recently adopted barefoot technique, a number of new barefoot-related running injuries are emerging among novice barefoot runners. The aim of this study was therefore to analyse the influence of three running conditions (natural barefoot [BF], barefoot with a forced rearfoot strike [BRS], and shod [SH]) on muscle activity and impact accelerations in habitually rearfoot shod runners. Twenty-two participants ran at 60% of their maximal aerobic speed while foot strike, tibial and head impact accelerations, and tibialis anterior (TA), peroneus longus (PL), gastrocnemius medialis (GM) and gastrocnemius lateralis (GL) muscle activity were registered. Only 68% of the runners adopted a non-rearfoot strike pattern during BF. Running BF led to a reduction of TA activity as well as to an increase of GL and GM activity compared to BRS and SH. Furthermore, BRS increased tibial peak acceleration, tibial magnitude and tibial acceleration rate compared to SH and BF. In conclusion, 32% of our runners showed a rearfoot strike pattern at the first attempts at running barefoot, which corresponds to a running style (BRS) that led to increased muscle activation and impact accelerations and thereby to a potentially higher risk of injury compared to running shod.  相似文献   

17.
BackgroundPrevious studies of foot strike patterns of distance runners in road races have typically found that the overwhelming majority of shod runners initially contact the ground on the rearfoot. However, none of these studies has attempted to quantify foot strike patterns of barefoot or minimally shod runners. This study classifies foot strike patterns of barefoot and minimally shod runners in a recreational road race.MethodsHigh-speed video footage was obtained of 169 barefoot and 42 minimally shod distance runners at the 2011 New York City Barefoot Run. Foot strike patterns were classified for each runner, and frequencies of forefoot, midfoot, and rearfoot striking were compared between the barefoot and minimally shod groups.ResultsA total of 59.2% of barefoot runners were forefoot strikers, 20.1% were midfoot strikers, and 20.7% were rearfoot strikers. For minimally shod runners, 33.3% were forefoot strikers, 19.1% were midfoot strikers, and 47.6% were rearfoot strikers. Foot strike distributions for barefoot and minimally shod runners were significantly different both from one another and from previously reported foot strike distributions of shod road racers.ConclusionFoot strike patterns differ between barefoot and minimally shod runners, with forefoot striking being more common, and rearfoot striking less common in the barefoot group.  相似文献   

18.
Purpose. We aimed to determine the effect of speed-induced changes in foot contact patterns on the vertical instantaneous loading rate (VILR). We hypothesized that transition runners, i.e. runners that shift towards a mid- (MF) or forefoot contact pattern (FF) when running speed increases, show smaller increases in VILR than non-transition runners, i.e. runners that remain with a rearfoot contact pattern (RF).

Methods. Fifty-two male and female runners ran overground at 3.2, 4.1, 5.1 and 6.2?m?s?1. Ground reaction forces, lower limb sagittal plane knee and ankle kinematics and plantar pressures were recorded. Multi-level linear regression models were used to assess differences between transition and non-transition runners.

Results. Non-transition runners experienced larger speed-induced increases in VILR (48.6?±?2.6?BW?s?1 per m?s?1) than transition runners (–1.4?±?7.6?BW?s?1 per m?s?1). Transition runners showed higher VILRs and a more flat foot touch down at the same pre-transition speed than non-transition runners.

Conclusion. When running speed increases, some runners transition towards more anterior foot contact patterns. This reduces or even eliminates the speed-induced increase in VILR. This result is especially the case for those RF runners who already have relatively high VILRs and flat foot positioning at slower running speeds.  相似文献   

19.
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20.
PurposeTo observe the relative change in foot-strike pattern, pressure characteristics, surface electromyography (sEMG) recordings, and stride characteristics in forefoot strike runners wearing both minimalist and traditional shoes during a 50-km run.MethodsFour experienced minimalist runners were enrolled in this study. Each runner ran a 50-km simulated run in both minimalist shoes and traditional shoes. Pressure data, sEMG recordings, and limited 3D motion capture data were collected during the initial 0.8 km and final 0.8 km for each trial.ResultsThree runners in the traditional shoe type condition and one runner in the minimalist shoe type condition demonstrated a more posterior initial contact area (midfoot strike (MFS) pattern) after the 50-km run, which was supported by increased activity of the tibialis anterior in the pre-contact phase (as per root mean square (RMS) values). In addition, in both pre- and post-run conditions, there were increased peak pressures in the minimalist shoe type, specifically in the medial forefoot. Muscle fatigue as defined by a decreased median frequency observed in isometric, constant force contractions did not correspond with our hypothesis in relation to the observed foot strike change pattern. Finally, step rate increased and step length decreased after the 50-km run in both shoe type conditions.ConclusionMore runners adopted a more posterior initial contact area after the 50-km run in the traditional shoe type than in the minimalist shoe type. The runners who adopted a more posterior initial contact area were more closely associated with an increased median frequency of the medial gastrocnemius, which suggests there may be a change in motor unit recruitment pattern during long-distance, sustained velocity running. The increased peak pressures observed in the medial forefoot in the minimalist shoe type may predispose to metatarsal stress fractures in the setting of improper training.  相似文献   

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