Barefoot and shod running: their effects on foot muscle kinetics

Running shoe technology has advanced significantly in the last 50 years, although the overall injury rate has yet to decrease. Barefoot (BF) running has become increasing more popular in the last 10 years. The current investigation aimed to explore differences in the forces produced by the foot muscles during BF and shod (SH) running. Fifteen male participants ran at 4.0 m.s-1 (± 5%). Kinematics were measured using an eight-camera motion analysis system alongside ground reaction forces. Peak and average stance phase forces from the flexor digitorum longus (FDL), flexor hallucis longus (FHL), peroneus longus (PL), extensor digitorum longus (EDL) and extensor hallucis longus (EHL) muscles were obtained using OpenSim v3.2. Peak and average forces of the FDL, FHL and PL muscles were significantly larger when running BF, whereas peak and average forces of the FHL and EHL muscles were significantly larger when running SH. This study supports the conjecture that the plantar muscles are required to work harder when running BF in relation to SH, indicating that BF training may serve to strengthen the foot musculature

Side to side differences in hamstring muscle kinematics during maximal instep soccer kicking

Hamstring strains are a common non-contact injury in soccer. The current study investigates bilateral differences in hamstring kinematics during maximal instep kicking. Thirteen male soccer players performed maximal instep kicks with their dominant and non-dominant limbs. Muscle-tendon kinematics of the four hamstring muscles during the kick movement were quantified using OpenSim software. Differences between dominant and non-dominant limbs were examined using paired t-tests. The results revealed that the biceps femoris long head (dominant = 165.28. ± 62.46 & non-dominant = 137.65 ± 52.17%), semimembranosus (dominant = 220.75 ± 43.35 & non-dominant = 131.23 ± 36.74%) and semitendinosus (dominant = 90.95 ± 16.69% and non-dominant = 80.47 ± 15.99%) experienced significantly greater strain when using the dominant limb. The current investigation provides key information regarding the mechanics of the hamstring group during maximal instep kicking, indicating that kicking with the dominant limb may place soccer players at increased risk from hamstring strain injury

Gender differences in limb and joint stiffness during the fencing lunge

The aim of the current investigation was to examine gender differences in limb and joint stiffness characteristics during the fencing lunge. Ten male and ten female fencers completed simulated lunge movements. Lower limb kinematics were collected using an eight camera optoelectric motion capture system which operated at 250 Hz. Measures of limb and joint stiffness were calculated as a function of limb length and joint moments divided by the extent of limb and joint excursion. Gender differences in limb joint stiffness parameters were examined statistically using independent samples t-tests. The results showed firstly that both limb (male = 64.22 ±19.12, female = 75.09 ±22.15 N.kg.m) and hip stiffness (male = 10.50 ±6.00, female = 25.89 ±15.01 Nm.kg.rad) were significantly greater in female fencers. In addition it was also demonstrated that knee moment (male = 1.64 ±0.23, female = 2.00 ±0.75 Nm.kg) was significantly larger in females. On the basis of these observations, the findings from the current investigation may provide further insight into the aetiology of the distinct injury patterns observed between genders in relation to fencing

The effect of minimalist, maximalist and energy return footwear of equal mass on running economy and substrate utilization

The aim of the current study was to explore the effects of minimalist, maximalist and energy return footwear of equal mass on economy and substrate utilisation during steady state running. Ten male runners completed 6 min steady state runs in minimalist, maximalist and energy return footwear. The mass of the footwear was controlled by adding lead tape to the lighter shoes. Running economy, shoe comfort, rating of perceived exertion and % contribution of carbohydrate to total calorie expenditure were assessed. Participants also subjectively indicated which shoe condition they preferred for running. Differences in shoe comfort and physiological parameters were examined using paired samples t-tests, whilst shoe preferences were tested using a chi-square test. The results showed firstly that running economy was significantly improved in the energy return (35.9 ml∙kg/min) compared to minimalist footwear (37.8 ml∙kg/min). In addition % carbohydrate was significantly greater in the minimalist (76.4%) in comparison to energy return footwear (72.9%). As running economy was improved and carbohydrate utilisation reduced in the energy return in comparison to minimalist footwear, the current investigation shows that these footwear are more economical when shoe mass is controlled

The influence of barefoot and shod running on Triceps-surae muscle strain characteristics

The aim of the current investigation was to determine the effects of barefoot and shod running on the kinematics of the Triceps-Surae muscle group. Twelve male participants ran at 4.0 m.s-1 (± 5%) in both barefoot and shod conditions. Kinematics were measured using an eight-camera motion analysis system. Muscle kinematics from the lateral Gastrocnemius, medial Gastrocnemius and Soleus were obtained using musculoskeletal modelling software (Opensim v3.2). The results showed that muscle strain for the lateral Gastrocnemius (barefoot = 1.10 & shod = 0.33 %), medial Gastrocnemius (barefoot = 1.07 & shod = 0.32 %) and Soleus (barefoot = 3.43 & shod = 2.18 %) were significantly larger for the barefoot condition. Given the proposed association between the extent of muscle strain and the etiology of chronic muscle strain pathologies, the current investigation shows that running barefoot may place runners at greater risk from Triceps-Surae strain injuries

Sex variation in patellar tendon kinetics during running

Purpose. The aim of the current investigation was to determine whether female recreational runners exhibit distinct patellar tendon loading patterns in relation to their male counterparts. Methods. Twelve male (age 26.55 ± 4.11 years, height 1.78 ± 0.11 m, mass 77.11 ± 5.06 kg) and twelve female (age 26.67 ± 5.34 years, height 1.67 ± 0.12 m, mass 63.28 ± 9.75 kg) runners ran over a force platform at 4.0 m · s –1. Lower limb kinematics were collected using an eight-camera optoelectric motion capture system which operated at 250 Hz. Patellar tendon loads were examined using a predictive algorithm. Sex differences in limb, knee and ankle joint stiffness were examined statistically using independent samples t tests. Results. The results indicate that patellar tendon force (male = 6.49 ± 2.28, female = 7.03 ± 1.35) and patelllar tendon loading rate (male = 92.41 ± 32.51, female = 111.05 ± 48.58) were significantly higher in female runners. Conclusions. Excessive tendon loading in female runners indicates that female runners may be at increased risk of patellar tendon pathologies

Effects of shoes on kinetics and kinematics of the squash forward lunge in male players

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.Squash is associated with a high incidence of chronic injuries. Currently there is a trend in many sports for players to select minimalist footwear. The aim of the current investigation was to examine the effects of squashspecific, running shoes and minimalist footwear on the kinetics and 3-D kinematics of the lunge movement in squash players. Twelve male squash players performed lunge movements whilst wearing minimalist, running shoe and squash-specific footwear. 3-D kinematics of the lower extremities were measured using an eightcamera motion analysis system alongside kinetic and tibial acceleration information which were obtained using a force platform and an accelerometer. Differences between footwear were examined using one-way repeated measures ANOVA. The results show firstly that loading rate parameters were significantly greater in the minimalist (average = 85.36B.W/s and instantaneous = 179.09B.W/s) footwear in relation to the squashspecific (average = 38.66 B.W/s and instantaneous = 50.73B.W/s) and running footwear (average = 37.62B.W/s and instantaneous = 48.14B.W/s). In addition, tibial acceleration parameters were also significantly greater in the minimalist (peak tibial acceleration = 8.45 g and tibial acceleration slope = 422.28g/s) footwear in relation to the squash-specific (peak tibial acceleration = 4.33 g and tibial acceleration slope = 182.57g/s) and running footwear (peak tibial acceleration = 4.81 g and tibial acceleration slope = 226.72g/s). The significant increase in impact loading in the minimalist footwear therefore suggests this type of shoe may place squash players at an increased risk of developing impact-related chronic injuries.Peer reviewedFinal Published versio

Multi-segment foot kinematics and plantar fascia strain during treadmill and overground running

Although physiologically beneficial, running is known to be associated with a high incidence of chronic injuries. Excessive coronal and transverse plane motions of the foot segments and strain experienced by the plantar fascia are linked to the development of a number of chronic injuries. This study examined differences in multi-segment foot kinematics and plantar fascia strain during treadmill and overground running. Twelve male recreational runners ran at 4.0 m.s-1 in both treadmill and overground conditions. Multi-segment foot kinematics and plantar fascia strain were measured using an eight-camera motion analysis system and contrasted using paired samples t-tests. The results showed that plantar fascia strain was significantly greater in the overground condition (8.23 ± 2.77) compared to the treadmill (5.53 ± 2.25). Given the proposed relationship between excessive plantar fascia strain and the etiology of injury, overground running may be associated with a higher incidence of injury although further work is necessary before causation can be confirmed

Giving order to image queries

Users of image retrieval systems often find it frustrating that the image they are looking for is not ranked near the top of the results they are presented. This paper presents a computational approach for ranking keyworded images in order of relevance to a given keyword. Our approach uses machine learning to attempt to learn what visual features within an image are most related to the keywords, and then provide ranking based on similarity to a visual aggregate. To evaluate the technique, a Web 2.0 application has been developed to obtain a corpus of user-generated ranking information for a given image collection that can be used to evaluate the performance of the ranking algorithm