Article

The Effect of Varying Midsole Hardness on impact Forces and Foot Motion during Foot Contact in Running

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Abstract

The purpose of this study was to investigate the influence of midsole hardness on both impact forces and rearfoot motion. Seven trained male long-distance runners were assessed with a Kistler force plate and with high-speed video, while running at 4.5 ± 0.1 m·s-1 with soft and hard shoe soles (EVA; soft shore Asker C40; hard shore Asker C65). The results showed smaller initial vertical impact peaks, occurring with a higher loading rate, and a significantly larger and faster initial eversion when subjects ran with hard shoes. Support is given to the concept that a more pronounced initial eversion offers an additional deceleration mechanism (Stacoff, Denoth, Kaelin, and Stuessi, 1988) also increasing the eccentric loading of the inverting muscles. On the other hand, during midstance soft shoe soles were found to produce a larger maximum eversion and pronation, also imposing an increased load on the same muscles. So, a good running shoe should be focused on a balance between reducing impact forces and reducing overpronation.

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... Therefore, in addition to anatomical factors, the use of orthoses [10], footwear [11], different types of sole [12], and running velocity [7] also seem to exert influence on pronation levels of the hindfoot. Hindfoot hyperpronation can be understood as a range of motion [5]; with regard to running velocity [7], it was observed that increases in velocity lead to significant increases in the maximal pronation angle and maximal pronation velocity. ...
... The MAP was determined by the difference between the relative angle (α) formed between the segments S1 (D-C) and S2 (A-B) [19], (Fig. 1), obtained in the flat foot phase (Fig. 2d) (highest value observed up to 40% of the support phase from the foot strike) and the angle found at the touch of the heel at the initial contact of the hindfoot (Fig. 2b). To track the points in the software, reflective markers were used, according to previous studies [12,21]. ...
... The sampling rate used in this study was 120 Hz (frames per second). After the test, the MAP of the right lower limb was analyzed through Kinovea software (version 0.8.25 Joan Charmant & Contrib) in 5 steps for each velocity [12]. The data were normalized individually. ...
Article
ABSTRACT The purpose of this study was to investigate the behavior of foot pronation at different percentages of peak of velocity in 23 physically active men. An ergospirometric test was carried out with an initial velocity of 9 km h-1 and increments of 1 km h-1 until exhaustion. 2D kinematic analysis was performed in the posterior frontal plane at all velocities to identify the MAP of the right leg. The analyzes were performed between the initial periods (0%), 25%, 50%, 75%, and 100% (peak of velocity - PV). All comparisons of the PV phases with the MAP showed an increase in the angle of foot pronation, with the exception of between the start and 25% of PV. Only 4 (∼ 17%) subjects maintained MAP values within a normal range until PV was reached. Control of the volume and intensity of training, as well as the running technique is suggested and strengthening of the muscles responsible for stabilization of the foot pronation. Keywords Foot PronationRunningSports Medicine Highlights • There is a positive effect of increased running intensity on increasing the maximal angle of pronation. • An increase in the running intensity exposes the individual to pronation beyond that considered normal. • Runners with low control of conditions and training environment will be more prone to the appearance of joint injuries from hyperpronation.
... During mechanical testing, shoes with soft midsoles demonstrate lower peak force and longer time to peak force than shoes with harder midsoles (Clarke, Frederick, & Cooper, 1983b;Shorten & Mientjes, 2011). However, in vivo test results are not as clear and effects of shoe cushioning on peak ground reaction force magnitudes are conflicting (Baltich, Maurer, & Nigg, 2015;Bates & Stergiou, 1996;Clarke et al., 1983b;De Wit, Clercq, De Lenoir, De Clercq, & Lenoir, 1995;Heidenfelder, Sterzing, & Milani, 2010;Kersting & Br€ uggemann, 2006;Logan, Hunter, Hopkins, Feland, & Parcell, 2010;Miller & Hamill, 2009;Nigg, Bahlsen, Luethi, & Stokes, 1987;Nigg & Bahlsen, 1988;Shorten & Mientjes, 2011). One reason for these conflicting reports is that response to footwear can vary widely among study subjects (Bates & Stergiou, 1996). ...
... More consistent group results are often observed for vertical loading rate of the ground reaction force during early stance. Compliant midsoles more consistently, but not always, reduce the loading rate of the vertical ground reaction force during the impact phase of running (Clarke et al., 1983b;De Wit et al., 1995;Heidenfelder et al., 2010;Milner, Ferber, Pollard, Hamill, & Davis, 2006;Pollard, Ter Har, Hannigan, & Norcross, 2018;Shorten & Mientjes, 2011). ...
... ankle) forces as well as greater ankle dorsiflexion and dorsiflexion velocity with a harder shoe. Similar to several other studies, Miller and Hamill also reported an increase in the ground reaction force loading rate when running in harder shoes (Clarke, Frederick, & Cooper, 1983a;De Wit et al., 1995;Heidenfelder et al., 2010;Shorten & Mientjes, 2011). This faster rate of loading was postulated to increase the rate of ankle dorsiflexion during early stance, rapidly lengthening the plantar flexors and resulting in a greater eccentric load. ...
Article
This study evaluated the effect of running shoes with differing midsole cushioning on ankle, knee and hip contact forces during running. Joint contact forces were estimated in 40 recreational runners (28 female, 12 male) while running over ground in three shoe conditions. Shoes differed only in midsole cushioning (45, 57 and 70 Asker C). Three-dimensional kinetics and kinematics were collected during running and input to a musculoskeletal model to estimate internal axial forces at the ankle, knee and hip. Multivariate ANOVA suggested that more cushioned shoes, relative to less cushioned shoes, reduced peak joint contact forces (p < 0.01) and load rates (p < 0.01). Ankle joint contact force and load rate were reduced with increased cushioning (p < 0.01) with moderate to large effects observed between pairwise comparisons (p ≤ 0.01–0.05, dz=0.41–1.35). Cushioning effects were also observed for knee joint contact force (p = 0.03) and loading rate (p < 0.01) with load reduction only seen when comparing the soft and hard shoes (p ≤ 0.05, dz=0.41–0.44). Midsole cushioning had less of an effect on hip contact force (p = 0.31) although hip contact force loading rate was influenced by midsole cushioning (p < 0.01) with lower rates observed for soft versus medium and hard shoe comparisons (p ≤ 0.01, dz=0.41–0.62). These results suggest that increasing shoe cushioning properties ∼10–20% may benefit individuals susceptible to high loads at the ankle, and to a lesser extent knee and hip, during running.
... 27 Most previous studies show that greater cushioning does not necessarily decrease the external impact experienced by the body. [4][5][6][15][16][17][18] The greater vertical loading rates observed with minimalist footwear as opposed to maximalist or traditional footwear conflicts with previous studies of maximalist footwear, [15][16][17][18] but are similar to 2 recent studies. 51,52 Decreased leg compression observed with the minimalist footwear indicates a straighter limb at initial contact 19 and occurs when running on a compliant surface. ...
... This similarity between computational methods likely reflects the research questions specific to this study and thus statistical similarity may not occur necessarily for studies investigating stiffness between different biomechanical conditions, such as differences in stiffness between speeds. 36,38,50 The shoe cushioning paradox emerged from studies reporting that cushioned footwear does not reduce external impact loading, [4][5][6][15][16][17][18] and so the benefits of cushioning came into question. It is important to highlight that internal loading or impact attenuation cannot be inferred from the present results or by any study reporting loading rates or impact shock alone. ...
... Some intervention studies have reported that the use of shock-absorbing insoles reduced the incidence of injury in military populations, 67,68 but footwear midsole hardness did not influence injury risk in 2 large-scale prospective randomized control trials of recreational runners. 69,70 In contrast to some [4][5][6][7][15][16][17][18]27 but not all previous studies, 18 we found that the shoe-cushioning paradox did not hold in this study. That is, runners in this study ran with greater average vertical loading rates in the footwear with the greatest average midsole stiffness, minimalist footwear, compared with maximalist and traditional footwear. ...
Article
The running footwear literature reports a conceptual disconnect between shoe cushioning and external impact loading: footwear or surfaces with greater cushioning tend to result in greater impact force characteristics during running. Increased impact loading with maximalist footwear may reflect an altered lower-extremity gait strategy to adjust for running in compliant footwear. The authors hypothesized that ankle and knee joint stiffness would change to maintain the effective vertical stiffness, as cushioning changed with minimalist, traditional, and maximalist footwear. Eleven participants ran on an instrumental treadmill (3.5 m·s-1) for a 5-minute familiarization in each footwear, plus an additional 110 seconds before data collection. Vertical, leg, ankle, and knee joint stiffness and vertical impact force characteristics were calculated. Mixed model with repeated measures tested differences between footwear conditions. Compared with traditional and maximalist, the minimalist shoes were associated with greater average instantaneous and average vertical loading rates (P < .050), greater vertical stiffness (P ≤ .010), and less change in leg length between initial contact and peak resultant ground reaction force (P < .050). No other differences in stiffness or impact variables were observed. The shoe cushioning paradox did not hold in this study due to a similar musculoskeletal strategy for running in traditional and maximalist footwear and running with a more rigid limb in minimalist footwear.
... In this context, studies have reported that high eversion velocities could be associated with medial tibial stress syndrome [1][2][3]. Aside from investigating injuries, previous studies examined the influence of footwear construction or foot orthoses [1,[4][5][6][7], exhaustion [8], and running pace [9] on maximum eversion velocity and the time until it occurs. ...
... One reason could be the individual walking and running gait of the subjects, which can slightly influence the measurement of evVel_Gonio and evVel_Gyro. Additionally, footwear conditions and locomotion velocities can influence rearfoot motion of subjects [4,5,9,12,22]. In our study, the softest shoe (AS) showed the lowest evVel compared to the harder shoes (PU and AD). ...
... In our study, the softest shoe (AS) showed the lowest evVel compared to the harder shoes (PU and AD). This is in line with previous findings [4,5,23]. While MD was similar for the footwear conditions during walking, there was a general trend of decreasing differences between evVel_Gyro and evVel_Gonio seen for all running velocities with decreasing footwear stiffness (AD > PU > AS) ( Table 2 and Figure 1). ...
Article
Full-text available
Gyroscopes have been used in previous studies to measure the peak angular velocity of the shoe or foot in the frontal plane (evVel). However, it is not clear whether different test conditions (footwear hardness or locomotion speed) can influence the accuracy of evVel. The purpose of the present study was to compare the accuracy of gyroscopes and electrogoniometers when measuring evVel and the time until evVel (t_evVel) in 12 different conditions using a single axis gyroscope attached to the heel cap. Twenty-four recreational runners were instructed to walk and run on a 15-m indoor track at four locomotion speeds (1.5, 2.5, and 3.5 m/s, and individual running speed) and in three footwear conditions (low to high hardness). The gyroscope data and electrogoniometer data were sampled at a rate of 1000 Hz. Comparisons between both measurement devices showed small mean differences up to 49.8 ± 46.9 deg/s for evVel and up to 5.3 ± 3.5 ms for t_evVel. Furthermore, strong relationships between gyroscope and electrogoniometer data were found for evVel as well as for t_evVel for all conditions. It can be concluded that gyroscopes can be used to accurately determine evVel and t_evVel under a variety of conditions.
... The second model uses four reference points: markers M1 and M2 (as in the previous model), marker 3 (M3), located at the origin of the Achilles tendon (calcaneal tendon), and marker 4 (M4), located at the origin of the Gastrocnemius muscle. In this model, the maximum subtalar pronation is determined by the maximum angle formed between the segments S1 and S2 (M3-M4) (see Wit et al. [17]). ...
... Two contrasting markers were placed on the midline of the heel counter of the shoe and two on the lower leg midline. See Figure 1 (cited by Wit et al. [17]). After the preparation phase, the treadmill was turned on, and the subjects completed a three-minute warm-up consisting of walking at a comfortable speed. ...
... Analysis of the maximum values of subtalar pronation of both feet found no significant differences between the values of each foot regardless of the mathematical method used. Similar results were reported by Wit et al. [17] and Tartaruga et al. [6]. Consequently, the behavior of the right leg (dominant) of each subject was chosen for analysis. ...
Article
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Introduction: Some authors have described the importance of physiological intensity in the behavior of the biomechanical aspects of running (for example, subtalar pronation), but the complex relationships between these variables are not yet well understood. Objective: This study investigated the influence of positive gradients on internal mechanical work (Wint) and maximum subtalar pronation at a submaximal running speed. Method: Sixteen male, trained long-distance runners (age: 29 ± 7 yr; stature: 1.72 ± 0.07 m; body mass: 72.1 ± 10.6 kg), performed four running economy tests (gradients: +1%, +5%, +10% and +15%, respectively) for four minutes at a same submaximal running speed to quantify the maximum values of subtalar pronation and predict the Wint values. Data were analyzed using descriptive statistics, Student’s T-test, and one-way repeated-measures (ANOVA) along with the Statistical Package for the Social Sciences (SPSS) version 20.0. Results: Wint increased according to the gradient (p < 0.05). However, no significant differences were observed in the maximum values of maximum subtalar pronation corresponding to each gradient. Conclusion: Results show the maximum subtalar pronation during submaximal running depends on the speed rather than intensity of effort.
... The explanation for this counterintuitive finding may lie in the well-recognized, but poorly understood phenomenon that highly cushioned shoes have a limited ability to reduce impact loading 6,9 . In fact, some studies have noted even a slight increase in impact loading when running in shoes with a compliant versus a hard midsole [10][11][12][13] . These findings counters the impact attenuation theory 14 and the results of in vitro mechanical impact tests 15 , both of which indicate a significant reduction in impact loading with increased cushioning. ...
... Our finding of greater impact loading when running in shoes with maximalist cushion conflicts with common assumptions 27 that additional cushioning should decrease impact loads. Several studies [10][11][12][13] have also noted a slight increase in IP and LR for runners in shoes with a compliant versus a hard midsole, but a mechanistic explanation for this phenomenon has remained poorly understood. A possible reason for the increased IP and LR for MAX shoes may be the fact that we observed significant differences in the spring-like running mechanics between the MAX and CON shoes. ...
Article
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Abstract Running shoe cushioning has become a standard method for managing impact loading and consequent injuries due to running. However, despite decades of shoe technology developments and the fact that shoes have become increasingly cushioned, aimed to ease the impact on runners’ legs, running injuries have not decreased. To better understand the shoe cushioning paradox, we examined impact loading and the spring-like mechanics of running in a conventional control running shoe and a highly cushioned maximalist shoe at two training speeds, 10 and 14.5 km/h. We found that highly cushioned maximalist shoes alter spring-like running mechanics and amplify rather than attenuate impact loading. This surprising outcome was more pronounced at fast running speed (14.5 km/h), where ground reaction force impact peak and loading rate were 10.7% and 12.3% greater, respectively, in the maximalist shoe compared to the conventional shoe, whereas only a slightly higher impact peak (6.4%) was found at the 10 km/h speed with the maximalist shoe. We attribute the greater impact loading with the maximalist shoes to stiffer leg during landing compared to that of running with the conventional shoes. These discoveries may explain why shoes with more cushioning do not protect against impact-related running injuries.
... Another key component of traditional trainers thought to affect running mechanics, is the external cushioning layer that is often not present in minimalist footwear and absent when BFT. An increased stiffness (or absence) of such cushioning has been reported to increase loading rates and peak pressures (De Wit, De Clercq, & Lenoir, 1995;Heidenfelder, Sterzing, & Milani, 2010;Shorten & Mientjes, 2011). Furthermore, observations have shown that reducing the level of shoe cushioning can increase peak plantar pressures at the midfoot and toe regions (Wiegerinck et al., 2009). ...
... The later occurrence of peak impact force and lower loading rates for SH running is consistent with findings regarding the effectiveness of compliant materials in footwear (De Wit et al., 1995;Heidenfelder et al., 2010;Shorten & Mientjes, 2011) and supports our second hypothesis. It is this external cushioning layer, present only in the SH condition, which is likely to be the mechanism behind the reduction in loading rates and delayed time to peak impact, particularly as the BFT and MS conditions are relying on the heel fat pad that provides very limited shock reduction and attenuation (De Clercq, Aerts, & Kunnen, 1994). ...
Article
Full-text available
Purpose: The aim was to compare footstrike modality and kinetics pre and post a seven week minimalist footwear transition programme.Methods: Ten recreational athletes (mass: 78.6 (8.7) kg, height: 179.4 (7.6) cm, age: 21.0 (0.7) years) performed overground running trials (3.8 m·s−1) whilst barefoot (BFT), minimal shod (MS) and shod (SH) both pre and post the programme. Ground reaction force and pressure data were simultaneously recorded for all footwear conditions. Footstrike modality was determined via visual inspection of the pressure distribution. Peak impact force, loading rate and peak regional pressures and impulses were compared pre and post, and between footwear conditions. The transition programme comprised of a two-week foot strengthening period followed by a five-week running transition.Results: Post transition there was a general trend for runners to adopt a more anterior footstrike in all three conditions. Additionally, loading rates and several peak pressures and impulses were found to decrease after the transition programme, with region specific changes evident for the effect of footwear. Furthermore, loading rates were higher whilst BFT and MS (instantaneous loading rates pre transition of 446.0 and 379.3 BW·s−1, respectively) compared to SH (105.8 BW·s−1).Conclusion: Whilst a seven-week MS transition programme was shown to decrease several kinetic variables, it was evident that both BFT and MS led to greater loading rates and peak pressures than SH running.
... Various studies reported that forefoot hardness influenced biomechanical variables (e.g. Baltich et al., 2015;Clarke et al., 1983;Cole et al., 1995;Wit et al., 1995). Hip, knee, and ankle range of motion, for instance, were affected in L1-and L2-runners alike (Kersting & ...
... Multiple authors concluded that there were no effects on tibial accelerations for L1-nor L2-runners (Hardin & Hamill, 2002;Oriwol et al., 2011). Across all runner levels (L1 -L3) contradictory results have been reported for GRF variables such as loading rates and/or impact peaks Cole et al., 1995;Oriwol et al., 2011;Sterzing et al., 2013;Sterzing, Custoza, et al., 2015;Wit et al., 1995). For instance, Oriwol and associates (2011) showed no effects of varying midsole hardnesses on ground reaction forces (L1/L2), but Baltich et al. (2015) reported reduced impact peaks in harder footwear conditions (L1/L2). ...
Article
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Matching running footwear features to the functional needs of specific groups of runners stratified according to their training status or running experience has the potential to improve footwear preference, enhance running performance, and reduce the risk of running-related injuries. The complexity of modern running shoes in combination with the various functional needs of specific groups of runners, however, introduces many confounding factors, disguising what an appropriate shoe design should entail. As a result, it is crucial to identify and synthesise the effects of systematically modified running footwear features on lower extremity biomechanics, performance, injury risk, and footwear preference in runners of different skill levels to advance the knowledge of running biomechanics and footwear. The databases Scopus and PubMed were searched for related studies and 895 articles were identified. After the application of exclusion criteria, 68 articles remained and were arranged in a matrix that highlighted the investigated footwear feature and runner level. The effects of 20 footwear features on lower extremity biomechanics, injury, performance, and preference in novice, recreational, and high calibre runners were synthesised. Laced uppers with harder midsole materials in the forefoot/lateral regions of the shoe and softer materials in the rearfoot/medial regions increased comfort and thus likely preference. To increase performance, footwear should be constructed as lightweight as possible, and implement a range of different bending stiffness for individual needs. Injury risks at the knee joint were reduced in footwear with thinner midsoles. For high calibre runners, specifically, insoles should be custom moulded to the shape of the foot, and special attention needs to be payed to the elasticity of the upper, in order to avoid detrimental shifts in running patterns.
... The explanation for this counterintuitive finding may lie in the well-recognized, but poorly understood phenomenon that highly cushioned shoes have a limited ability to reduce impact loading 6,9 . In fact, some studies have noted even a slight increase in impact loading when running in shoes with a compliant versus a hard midsole [10][11][12][13] . These findings counters the impact attenuation theory 14 and the results of in vitro mechanical impact tests 15 , both of which indicate a significant reduction in impact loading with increased cushioning. ...
... Our finding of greater impact loading when running in shoes with maximalist cushion conflicts with common assumptions 27 that additional cushioning should decrease impact loads. Several studies [10][11][12][13] have also noted a slight increase in IP and LR for runners in shoes with a compliant versus a hard midsole, but a mechanistic explanation for this phenomenon has remained poorly understood. A possible reason for the increased IP and LR for MAX shoes may be the fact that we observed significant differences in the spring-like running mechanics between the MAX and CON shoes. ...
... The factors that affect the magnitude of vertical ground reaction force (vGRF) include velocity, landing elevation, shoe type, body weight, position and landing surface, and landing strategy. Increasing the elevation increases the reaction force of the ground and increases the load on the joints [19,20]. The results showed that the higher the ground reaction force, the higher the torque in the knee joint and the ankle joint; therefore, the amount of damage to these two joints may increase with increasing reaction forces. ...
Article
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This study aims to compare the dynamic parameters of professional elite volleyball players when landing from different heights. 15 volleyball players selected based on availability participated in the study. The studied skill for different heights was set to a percentage of the maximum jump elevation (100%-75%-50%). A repeated-measures ANOVA model was used to determine the measurement variance differences using SPSS software version 24. The results showed that landing from a higher height increased the angular velocity of the rotational axis of the foot while the peak of angular acceleration was lower at the highest elevation. The linear velocity peak also showed lower values at the highest elevation, while the linear acceleration increased with increasing landing elevation. Despite the insignificant effect of different heights on the vertical ground reaction force (vGRF) factor, the peak of ankle joint torque in the anterior-posterior axis increased with increasing elevation. Similarly, the maximum ankle angle in the anterior-posterior axis was higher at high elevation than at low elevation. The results showed that volleyball players try to improve the absorption of energy by increasing the range of motion of the ankle joint in the anterior-posterior axis at high elevations.
... Meanwhile, during locomotion, the decrease in lower-limb range of motion and the increase in PVF further increase leg stiffness (Butler et al., 2003;Grimston, Engsberg, Kloiber, & Hanley, 1991), and the two factors reportedly contribute to an increased risk of stress fractures Grimston et al., 1991) and load factors related to increased impact on the lower limbs (Hennig & Lafortune, 1991). Load factor in particular is a measure of stress application rate on the organs (Cook, Farrell, Carey, Gibbs, & Wiger, 1997;Wit, Clercq, & Lenoir, 1995), and the stress degree during a unit of time can be interpreted quantitatively (Hargrave, Carcia, Gansneder, & Shultz, 2003). This implies that there is a need for future research that simultaneously analyzes the relationship between leg stiffness and load factor to elucidate the factors contributing to injuries by changes in loads during running. ...
... However, conflicting results were reported on this topic. Some studies found a reduced impact load associated to an increased shoe cushioning (De Wit, De Clercq, & Lenoir, 1995;O'Leary, Vorpahl, & Heiderscheit, 2008;Shorten & Mientjes, 2011). Conversely, some studies reported an opposite response, i.e. more shoe cushioning inducing larger vertical peak ground reaction force (Baltich, Maurer, & Nigg, 2015;Hennig, Valiant, & Liu, 1996;Nigg, Bahlsen, Leuthi, & Stokes, 1988). ...
Article
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Most of the studies investigated footwear cushioning through the quantification of impact load or running-related injuries. Few studies focused on users’ perception of footwear cushioning. Users’ perception is usually investigated in other domains like food and consumer products using the ‘Sensory Trained Panel’ method. The purpose of this study was to assess the relationship between women's perception of shoe cushioning and mechanical properties of running shoes using a sensory trained panel approach. An initial mechanical characterization enabled to select 10 shoes having a wide range of mechanical properties. Ten recreational women runners were trained to become a ‘Sensory Trained Panel.’ First, simple vocabulary and gestures were highlighted to make shoe feature definition explicit and understood by all participants. Then, participants were trained to become discriminant, repeatable and in consensus for the rating of a given shoe feature. Finally, after running with a shoe model, participants rated the shoe feature intensity on a linear scale. The order of shoe models was balanced to avoid any effect of rank, sequence and fatigue. Each footwear model was available in four copies to limit alterations of shoe properties due to repetitive use. All the shoe models were blinded to avoid any effect of shoe design on the sensory evaluation. ‘Heel penetration’ was the explicit shoe feature understood by all participants to describe shoe cushioning. Panel performances were statistically verified. A significant correlation was highlighted and enabled to predict users’ perception of heel penetration based on shoe absolute maximal compression (r = 0.86, p = 6.9 × 10⁻⁴). The sensory trained panel method seemed powerful to quantify the perception of shoe features and could be used for other purposes than correlation between sensory and mechanical data.
... The increasing influence of the loading implies poor shock absorption and imposing high level of pressure on lower limb in a short time [14]. Factors that affect the load volume include speed of movement, landing height, type of shoes, trunk weight, location and level of the landing as well as landing strategy [15]. Vertical ground reaction forces are parameters that describe a person's landing in terms of the severity [13]. ...
Article
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Purpose: Core stability training (CST) has increased among athletes. The study hypothesis is that neuromuscular training and exercises of central area of trunk, pelvis and hip can reduce injury risk, and specifically peak vertical ground reaction forces in drop landing task. Therefore, the objective of this study was to evaluate kinetics during single leg drop landing test following a CST intervention. Methods: The present research was a quasi-experimental study with pretest/posttest and a control group. After giving their informed written consent, 30 athletes (15 in the experimental group, and 15 in the control group) volunteered to participate in the training program consisting of CST sessions, 3 times per week for 8 weeks. Training group was performed the CST during 8 weeks but control group did not perform these exercises. Kinetics variables in pretest and posttest during single-leg drop landing were measured by motion analysis and force plate device. To compare the obtained data, mixed ANOVA repeated measure at significance level of P
... The increasing influence of the loading implies poor shock absorption and imposing high level of pressure on lower limb in a short time [14]. Factors that affect the load volume include speed of movement, landing height, type of shoes, trunk weight, location and level of the landing as well as landing strategy [15]. Vertical ground reaction forces are parameters that describe a person's landing in terms of the severity [13]. ...
Article
Full-text available
Purpose: Core stability training (CST) has increased among athletes. The study hypothesis is that neuromuscular training and exercises of central area of trunk, pelvis and hip can reduce injury risk, and specifically peak vertical ground reaction forces in drop landing task. Therefore, the objective of this study was to evaluate kinetics during single leg drop landing test following a CST intervention. Methods: The present research was a quasi-experimental study with pretest/posttest and a control group. After giving their informed written consent, 30 athletes (15 in the experimental group, and 15 in the control group) volunteered to participate in the training program consisting of CST sessions, 3 times per week for 8 weeks. Training group was performed the CST during 8 weeks but control group did not perform these exercises. Kinetics variables in pretest and posttest during single-leg drop landing were measured by motion analysis and force plate device. To compare the obtained data, mixed ANOVA repeated measure at significance level of P<0.05 was used. All analyses were done by SPSS 22. Results: The results revealed that the peak vertical ground reaction forces, loading rate, and average loading rate significantly reduced following 8 weeks CST intervention (P<0.05). Conclusion: This study shows evidence that core stability training improves landing kinetics, and may reduce lower extremity injury risk in athletes.
... However, conflicting results were reported on this topic. Some studies found a reduced impact load associated to an increased shoe cushioning (De Wit, De Clercq, & Lenoir, 1995;O'Leary, Vorpahl, & Heiderscheit, 2008;Shorten & Mientjes, 2011). Conversely, some studies reported an opposite response, i.e. more shoe cushioning inducing larger vertical peak ground reaction force (Baltich, Maurer, & Nigg, 2015;Hennig, Valiant, & Liu, 1996;Nigg, Bahlsen, Leuthi, & Stokes, 1988). ...
Article
Abstract download: http://www.tandfonline.com/eprint/Eif7Yb2QaYzmZzhkkhQZ/full
... Players wearing shoes with SO showed higher ankle dorsiflexion and inversion than when wearing shoes with HO. During the stance of 45° cut, soft outsoles were found to achieve higher maximum pronation, and this would result in more loading to the medial side of the ankle (De Wit et al., 1995). Compared with wearing shoes with HO, the force-time integral in MFF was significantly higher when wearing shoes with SO. ...
Article
The purpose of this study was to investigate the effect of different outsole hardness of turf cleats shoes on the lower limb kinematics and kinetics of soccer players playing on artificial turf. The participants were required to complete tasks of straight running and 45° left sidestep cutting movements, respectively, at the speed of 4.5 ± 0.2 m/s on artificial turf. They were asked to randomly select turf cleats shoes with a soft outsole (SO), medium hardness outsole (MO) and hard outsole (HO). During the stance phase of straight running, peak pressure and force-time integral in medial forefoot (MFF) of players wearing cleats shoes with MO were significantly higher than those wearing cleats shoes with SO. During the stance phase of a 45° cutting maneuver, players wearing cleats shoes with SO showed significantly higher peak knee flexion and abduction angles than the HO group. Players wearing cleats shoes with SO also showed higher ankle dorsiflexion and inversion angles compared with those wearing cleats shoes with HO. The vertical average loading rate (VALR) as well as peak pressure and force-time integral in the heel (H) and lateral forefoot (LFF) regions of players wearing cleats shoes with HO were significantly higher than those wearing shoes with SO. On the contrary, peak pressure and force-time integral of players wearing shoes with SO were significantly higher than those wearing shoes with HO in MFF. A higher vertical loading rate and plantar pressure of some areas may increase the potential risk of metatarsal stress fractures and plantar fasciitis. Therefore, this finding about turf cleats shoes could give some theoretic support for the design of turf cleats shoes and material optimization in the future.
... Indeed asymmetry during able-bodied ambulation is well established in literature and linked to functional differences between limbs. 19,22 Although previous studies indicate that changing footwear sole stiffness has an effect on spatio-temporal parameters of gait in normal participants, 23 because of the focus on diabetic neuropathy and the structure of the present study the aforementioned changes in gait were not assessed. This could be the subject to further investigations, however it could be anticipated that this effect would be less prominent in people with impaired sensation in their feet, namely people with diabetic neuropathy. ...
Article
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Current selection of cushioning materials for therapeutic footwear and orthoses is based on empirical and anecdotal evidence. The aim of this investigation is to assess the biomechanical properties of carefully selected cushioning materials and to establish the basis for patient-specific material optimisation. For this purpose, bespoke cushioning materials with qualitatively similar mechanical behaviour but different stiffness were produced. Healthy volunteers were asked to stand and walk on materials with varying stiffness and their capacity for pressure reduction was assessed. Mechanical testing using a surrogate heel model was employed to investigate the effect of loading on optimum stiffness. Results indicated that optimising the stiffness of cushioning materials improved pressure reduction during standing and walking by at least 16 and 19% respectively. Moreover, the optimum stiffness was strongly correlated to body mass (BM) and body mass index (BMI), with stiffer materials needed in the case of people with higher BM or BMI. Mechanical testing confirmed that optimum stiffness increases with the magnitude of compressive loading. For the first time, this study provides quantitative data to support the importance of stiffness optimisation in cushioning materials and sets the basis for methods to inform optimum material selection in the clinic. Electronic supplementary material The online version of this article (doi:10.1007/s10439-017-1826-4) contains supplementary material, which is available to authorized users.
... 28 However, the softer the sole of the shoe, the greater the risk of overpronation movement. 29 A previous study already suggested that a certain degree of additional stability may be beneficial even for those individuals with neutral foot posture. 9 This could be especially true for shoes with soft midsoles. ...
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Background/aim: This randomised controlled trial investigated if the usage of running shoes with a motion control system modifies injury risk in regular leisure-time runners compared to standard shoes, and if this influence depends on foot morphology. Methods: Recreational runners (n=372) were given either the motion control or the standard version of a regular running shoe model and were followed up for 6 months regarding running activity and injury. Foot morphology was analysed using the Foot Posture Index method. Cox regression analyses were used to compare injury risk between the two groups, based on HRs and their 95% CIs, controlling for potential confounders. Stratified analyses were conducted to evaluate the effect of motion control system in runners with supinated, neutral and pronated feet. Results: The overall injury risk was lower among the participants who had received motion control shoes (HR=0.55; 95% CI 0.36 to 0.85) compared to those receiving standard shoes. This positive effect was only observed in the stratum of runners with pronated feet (n=94; HR=0.34; 95% CI 0.13 to 0.84); there was no difference in runners with neutral (n=218; HR=0.78; 95% CI 0.44 to 1.37) or supinated feet (n=60; HR=0.59; 95% CI 0.20 to 1.73). Runners with pronated feet using standard shoes had a higher injury risk compared to those with neutral feet (HR=1.80; 95% CI 1.01 to 3.22). Conclusions: The overall injury risk was lower in participants who had received motion control shoes. Based on secondary analysis, those with pronated feet may benefit most from this shoe type.
... The authors found significant differences in the temporal variables, for example in cadence, speed during gait, time of the stance phase and balance, among others. On the other hand, De Witt et al. (31) evaluated running shoes with different hardnesses in midsole and, found greater magnitude of the first vertical peak force on the footwear with greater hardness in comparison to the lower hardness shoes and the time to reach the first peak was higher for the softer footwear. It is believed that the results of Figure 3 for the footwear situation may be related to the modification of kinematic motion, i.e., there is a change in the pattern of motion when the subject uses unstable footwear (6). ...
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Introduction Footwear is no longer just an accessory but also a protection for the musculoskeletal system, and its most important characteristic is comfort. Objectives This study aims to identify and to analyze the vertical ground reaction force in barefoot women and women with unstable shoes. Methodology Five women aged 25 ± 4 years old and mass of 50 ± 7 kg participated in this study. An AMTI force plate was used for data acquisition. The 10 trials for each situation were considered valid where the subject approached the platform with the right foot and at the speed of 4 km/h ± 5%. The instable shoe of this study is used in the practice of physical activity. Results The results showed that the first peak force was higher for the footwear situation, about 5% and significant differences between the barefoot and footwear situation. This significant difference was in the first and second peaks force and in the time of the second peak. Conclusion The values showed that the footwear absorbs approximately 45% of the impact during gait.
... This explanation is supported by the similar impact force across footwear conditions despite suggested differences in cushioning and is consistent with the literature. 43,44,45 Additional plantar flexion can also serve as a method to reduce impact force during lateral movements, 18 although there was no statistical evidence of this in the current investigation. The study therefore provides no support to the thought that peak impact force and possible lower extremity loading was lower with the cushioned footwear compared to the high-cut basketball shoe. ...
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Ankle inversion injury is extremely common in basketball, whereby rearfoot inversion and ankle plantar flexion is greater in those with injury. The current study analysed the response of recreational basketball players to three different footwear conditions; high-cut basketball shoe, low-cut running shoe and low-cut running shoe with ankle brace. Ten recreational male basketball players performed 45? ?v?-cut movements at an approach speed of 4.5m/s. Dependent variables included peak initial rearfoot inversion and ankle plantar flexion. Peak impact force was also measured due to the potential difference in cushioning provided by the footwear. Repeated measures ANOVA were used to compare dependent variables with statistical significance accepted at p < 0.05. Results indicated that there were no significant difference for plantar-flexion (F = 2.94, p > 0.05; Partial ?2 = 0.25) and impact force (F = 3.189, p > 0.05, Partial ?2 = 0.26). On the other hand, comparison of peak rearfoot inversion showed that there was significant differences between the footwear condition (F = 33.36, p < 0.05, Partial ?2 = 0.788). Pairwise comparisons with Bonferroni adjustments showed significantly larger peak initial rearfoot inversion values for the high-cut basketball shoe compared to both the low-cut running shoe (p = 0.001) and the low-cut running shoe with brace condition (p = 0.001). Findings indicate the potential for using low-cut running shoes for recreational basketball without an increased injury risk.
... The effects of different footwear on the musculoskeletal system are often assessed by interpreting the resultant ground reaction force acting at the foot during the stance phase of running. The heel impact peak and the loading rate are often extracted from the ground reaction force to make conclusions on the beneficial or harmful effects of different design features such as heel pad thickness, heel structure, or midsole material (2,7,8,18). However, the functional interpretation of results using these variables with respect to their beneficial or harmful effects on the musculoskeletal system is the subject of current debate in the literature (19). ...
Article
The effects of footwear on the musculoskeletal system are commonly assessed by interpreting the resultant force at the foot during the stance phase of running. However, this approach overlooks loading patterns across the entire foot. An alternative technique for assessing foot loading across different footwear conditions is possible using comprehensive analysis tools that extract different foot loading features, thus enhancing the functional interpretation of the differences across different interventions. The purpose of this paper was to use pattern recognition techniques to develop and utilize a novel comprehensive method for assessing the effects of different footwear interventions on plantar loading. A principal component analysis (PCA) was used to extract different loading features from the stance phase of running, and a support vector machine (SVM) was used to determine if and how these loading features were different across 3 shoe conditions. The results revealed distinct loading features at the foot during the stance phase of running. The loading features determined from the PCA allowed successfully classifying all 3 shoes conditions using the SVM. Several differences were found in the location and timing of the loading across each pairwise shoe comparison using the output from the SVM. The analysis approach proposed can successfully be used to compare different loading patterns with a much greater resolution than has been reported previously. This study has several important applications. One such application is that it would not be relevant for a user to select a shoe or for a manufacturer to alter a shoe's construction if the classification across shoe conditions would not have been significant.
... A taxa de aplicação tem sido considerada como um melhor indicador de absorção de carga mecânica do que o pico de força de impacto [17] [18]. Tem sido documentado que em relação ao piso duro a taxa de aplicação de força em exercícios realizados sobre o minitrampolim apresenta-se 80% menor [19]. ...
Article
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Resumo: O objetivo desse estudo foi classificar os exercícios executados sobre o minitrampolim JUMP FIT® a partir da força de reação vertical. Sessenta professores credenciados executaram 13 exercícios no minitrampolim instrumentado com 6 células de carga. Para avaliação dos dados foram selecionados 45 segundos de execução e 20 picos consecutivos de força e de taxa de aplicação foram anotados, normalizados pelo peso corporal do indivíduo. Para análise dos dados foram utilizados os testes estatísticos: teste t de Student para amostra pareadas, teste Anova one way e o post hoc Bonferroni (p < 0,05). Em relação ao pico de força sugere-se a seguinte classificação: grupo (1), inferior a 3x PC; grupo (2), 3 a 4x PC; grupo (3), acima de 4x PC. Em relação a taxa de aplicação de força: grupo (1) inferior a 20xPC/s; grupo (2), de 20 a 30x PC/s e grupo (3), acima de 50x PC/s. Palavras-Chave: JUMP FIT®, força de reação do solo, taxa de aplicação de força. Abstract: The aim of this study was to classify the ground reaction forces inexercises performed in the mini springboard JUMP FIT®. Sixty work out teachers performed the exercises on a mini springboard instrumented with six loads cells. For the data evaluating 45 seconds of execution were selected, and 20 consecutives peaks forces and power loading rates were noted and normalized by body weight (BW) of each subject. The data analyses used the statistics' tests: Paread test t Student, anova one way and post hoc Bonferroni (p < 0,05). The following classificaton was sugested to the peaks forces: group(1), less then 3x BW; group (2), 3 to 4x BWPC; groud (3), 4x or more BW. The power loading rate was classified: group (1) less then 20x BW/s; group (2), 20 to 30x BW/s and group (3), 50x or more BW/s.
... ). Additionally, it has been shown that hardness of the shoe midsole has significant effects on the kinematics and kinetics of the foot during the stance phase of running gait(De Wit, De Clercq, & Lenoir, 1995;Hamill, Bates, & Holt, 1992; ...
... 8 While there is no dearth of literature on the influence of shoe midsole hardness on stability, most studies were done on running which predominantly involves forward motion in a straight line. [9][10][11][12][13] It is important to note that lateral cutting and jump landing movements occur frequently during basketball games in addition to forward movements. Furthermore, basketball shoes are distinct from walking or running footwear since each type of footwear should be customized for performance of a specific activity, which imposes specific functional demands on shoe properties. ...
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This study aimed to investigate the effects of varying midsole hardness on center of pressure (COP) and perceived stability during basketball-specific tasks, as well as the correlation between COP and perception measurements. Twenty male basketball players performed 45° cutting and lay-up while wearing basketball shoes with soft and hard midsoles. COP trajectories were obtained from the Pedar insole system. Stability perceptions at the forefoot and rearfoot were assessed using 150-mm visual analogue scales (VAS). Results indicated greater COP mediolateral deviations in soft midsole compared with hard midsole during lay-up (soft 16.6 ± 4.7 mm, hard 15.8 ± 4.6 mm, p = .025) but not 45° cutting (soft 15.7 ± 5.9 mm, hard 15.8 ± 5.6 mm, p = .601). While 16 out of 20 participants preferred soft midsole, no significant difference in VAS ratings was found between shoes for both tested movements. There was no significant correlation between COP and perceived stability during lay-up or 45° cutting. In conclusion, midsole hardness of basketball shoes did not consistently affect mediolateral stability of the foot during 45° cutting and lay-up. Subjective perception alone cannot be used to indicate mediolateral deviation of the foot when executing basketball-specific maneuvers.
... Athletes with higher loading rates are subjected to greater impact with a short period, making it difficult to properly dissipate the forces reaching the knee joint than in athletes with a lower loading rate [22]. Adult males showing relatively lower ACL injury rates have reduced peak loading rates than adult females [23][24][25]. In addition, landing specialists (parkour athletes) exhibited a lower loading rate than recreationally trained individuals [26]. ...
Article
Background: During landing, the ankle angle at initial contact (IC) exhibits relatively wide individual variation compared to the knee and hip angles. However, little is known about the effect of different IC ankle angles on energy dissipation. Research question: The purpose of this study was to investigate the relationship between individual ankle angles at IC and energy dissipation in the lower extremity joints. Methods: Twenty-seven adults performed single-leg landings from a 0.3-m height. Kinetics and kinematics of the lower extremity joints were measured. The relationship between ankle angles at IC and negative work, range of motion, the time to peak ground reaction force, and peak loading rate were analyzed. Results: The ankle angle at IC was positively correlated with ankle negative work (r = 0.80, R2 = 0.64, p < 0.001) and the contribution of the ankle to total (ankle, knee and hip joint) negative work (r = 0.84, R2 = 0.70, p < 0.001), but the ankle angle was negatively correlated with hip negative work (r = -0.46, R2 = 0.21, p = 0.01) and the contribution of the hip to total negative work (r = -0.61, R2 = 0.37, p < 0.001). The knee negative work and the contribution of the knee to total negative work were not correlated with the ankle angle at IC. The ankle angle at IC was positively correlated with total negative work (r = 0.50, R2 = 0.25, p < 0.01) and negatively correlated with the peak loading rate (r = -0.76, R2 = 0.57, p < 0.001). Significance: These results indicated that landing mechanics changed as the ankle angle at IC increased, such that the ankle energy dissipation increased and redistributed the energy dissipation in the ankle and hip joints. Further, these results suggest that increased ankle energy dissipation with a higher IC plantar flexion angle may be a potential landing technique for reducing the risk of injury to the anterior cruciate ligament and hip musculature.
... Attempts to provide a representation of foot kinematics in athletic footwear using two dimensional (2D) analysis or three dimensional (3D) stereophotogrammetry has been based on markers applied to the external surface of the shoe (McCulloch et al. 1993, Eng and Pierrynowski 1994, De Wit et al. 1995, Nigg et al. 2003, Nigg et al. 2006). This has been extended to evaluating the effect of different footwear design parameters such as lateral heel flares (Nigg and Bahlsen 1987), heel height (Clarke et al. 1983), midsole materials and composition (McNair and Marshall 1994) on foot and lower extremity kinematics. ...
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Movement of the foot and ankle are essential for human locomotion. Recent in vivo research using invasive techniques has highlighted the complexity of joint kinematics of the foot and ankle. Consequently, a detailed quantification of foot bone motion is often required. This presents challenges if non-invasive methods are used; even more so if footwear is incorporated into these investigations. A description of foot movement within footwear (in-shoe foot kinematics) is particularly valuable due to the plethora of potential applications in foot and ankle biomechanics. The objective of this review is to appraise existing literature and describe methods for quantifying foot kinematics inside athletic running type footwear and to provide a perspective on future directions for research. A number of methods were identified that have been implemented in an attempt to quantify in-shoe foot kinematics. Although varied, these all present threats to the validity of measurement in the form of either structural modification of footwear or surface marker application to the external shoe surface. Due to discrepancies in foot kinematics measured with markers applied on the external shoe surface compared to skin or bone mounted markers, it appears inappropriate to rely on external shoe markers to infer in-shoe foot motion. The impact of footwear modification on shoe structure and foot kinematics to gain access to anatomical landmarks of the foot requires further investigation. The recognition of the limitations imposed by these methods and the emergence of new non-invasive methods that allow for investigation during shod activity will facilitate more realistic representation and accurate investigation of foot motion inside the shoe.
... This supports the findings observed in a recent study [18] of 50-km runners, where the peak pressures were significantly greater in the minimalist shoe type, especially in the medial forefoot. This confirms that the construction of CRS is designed to absorb strong impacts accompanying the initial stage of the stance in the area of the sole [20]. ...
Article
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Shoe type and their hardness play an important role in the characteristics of gait cycle. Runners usually use a conventional running shoes (CRS) and also in the last years' minimalist running shoes (MRS) with a thin, flexible outsole or they run barefoot. The type of shoes reportedly affects the magnitude of the vertical ground reaction forces when running The aim of this study was to analyse foot strike pattern according to plantar pressure distribution and dynamic characteristics of running gait in a group of recreational runners (8 men and 7 women; mean±SD; age = 34.6±6.2 years, body height = 1.81±0.08 m, body weight = 68.10±8.9 kg) when using minimalist and conventional running shoes. The Pedar system (Pedar-X®, Novel, Munich, Germany) with measuring insoles was used to record plantar pressure distribution and vertical ground reaction forces under the foot, heel, midfoot and forefoot. For the same type of foot-strike pattern, impact forces are higher for MRS than for CRS, which is why runners using MRS modify their foot-strike pattern with the aim of reducing these impact forces. The foot-strike pattern changed in 5 runners when using minimalist shoes. The foot strike pattern shifted from middle-foot strike to forefoot strike or from rear-foot strike to middle-foot strike when running in MRS. Plantar pressure distribution was different when running in MRS and in CRS. When running in MRS the Peak pressure values under the foot were significantly higher than values when using CRS. Peak pressure values and vertical ground reaction forces under the heel were in MRS higher only in a group of rear-foot strikers. The values of Peak pressure and vertical ground reaction forces related to CRS were in the area of the midfoot and forefoot higher, but the differences were not statistically significant (p > 0.05; n = 15).
... The results presented are important from the practical point of view, since, although the magnitude of the forces involved and the loading rate of those forces were considered important in relation the risk of muscularskeletal injury, both act differentially on the structures of the human body. Data has shown, for example, that the force loading rate may be a better indicator of the absorption of mechanical load than the peak force value (De Wit, De Clercq & Lenoir, 1995;Dixon, Collop & Batt, 2000). ...
... As would be expected from common sense, researchers made the hypothesis that better the footwear cushioning, the lower the passive peak. However, even if some studies showed a lower passive peak with more compliant cushioning shoes (O'Leary, Vorpahl, & Heiderscheit, 2008;Logan, Hunter, Hopkins, Feland, & Parcell, 2010), some did not show any difference (Clarke, Frederick, and Cooper, 1983;Heidenfelder, Sterzing, & Milani, 2010;Kersting & Bruggemann, 2006) and others observed an increase (De Wit, De Clercq, & Lenoir, 1995;Nigg, Bahlsen, Luethi, & Stokes, 1987;Nigg, Sterzog, & Read, 1988). The passive peak seemed, therefore, to not be relevant to assess footwear cushioning. ...
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Objective: To investigate the relationship between the perception of cushioning and variable measured using tibia acceleration in heel–toe running. Method: Ten rearfoot strikers’ runners ran at 3.9 m.s⁻¹ on a stiff treadmill in seven footwear conditions presenting different mechanical properties through midsole geometries and/or materials. The perceived cushioning was quantified through a 100-mm visual analogic scale. Tibia accelerations were measured using a triaxial accelerometer from which six variables of interest were extracted based on time and frequency analyses. After pooling data of each subject in each condition (n = 70), Pearson correlation coefficients were calculated to test the correlation between the perceived cushioning and each biomechanical variables. The Cohen’s d effect size was calculated for significant correlation. Results: Significant correlations were found between the perceived cushioning and three axial acceleration-related variables which are the axial acceleration peak (r = −0.246, p = .04, small correlation), the kurtosis coefficient of the axial acceleration peak (r = −0.281, p = .056, small correlation), and the power spectral density of the axial acceleration within the 10–20 Hz bandwidth (r = −0.300, p = .018, small correlation). Conclusion: The present study highlights that the perception of running footwear cushioning was correlated to tibia impact peak and tibia vibration magnitude. Besides, no variable extracted from the transverse component of tibia acceleration was correlated to cushioning perception. These findings could have practical implications in running footwear design.
... Over the last forty years of research on running biomechanics, one area which has received considerable emphasis is the influence of shoe cushioning on running mechanics (Bates et al., 1983;Clarke et al., 1983;De Wit et al., 1995;Hennig et al., 1996;Milani et al., 1997;Nigg et al., 1988Nigg et al., , 1987Wakeling et al., 2002). These studies all evaluate how cushioning influences running mechanics in traditional running shoes. ...
Article
While several studies have examined kinematic and kinetic differences between maximalist (MAX), traditional (TRAD), or partial minimalist (PMIN) shoes, to date it is unknown how MAX shoes influence muscle activity. This study compared lower extremity kinematics and muscle activity when running in PMIN, TRAD, and MAX shoes. Thirteen participants ran in each shoe while whole body kinematics were recorded using motion capture and electromyography was recorded from seven leg muscles. Differences in kinematics and root mean square amplitudes (RMS) were compared between shoe conditions. There were small differences in sagittal and frontal plane ankle kinematics between shoe conditions, with the MAX shoes resulting in less dorsiflexion at foot strike (p = .002) and less peak dorsiflexion (p < .001), and the PMIN shoes resulting in greater peak eversion (p = .012). Gluteus medius (p.006) and peroneus longus (p = .007) RMS amplitudes were greater in the MAX shoe then the TRAD or PMIN shoes while tibialis anterior RMS amplitudes were higher in the PMIN shoes (p = .005) than either the TRAD or MAX shoes. Consistent with previous findings, these results suggest there are small differences in kinematics when running in these three shoe types. This may partly be explained by the changes in muscle activity, which may be a response in order to maintain a preferred or habitual movement path. Implications for these difference in muscle activity in terms of fatigue or injury remain to be determined.
... Therefore, footwear conditions only differed in the midsole material, which was comprised of polyurethane elastomer (hardness: 45 shore C, density: 0.216, resilience: 66%, and compression set: 45.6%) or traditional vinyl acetate (hardness: 55 shore C, density: 0.220, resilience: 54%, and compression set: 79.0%); a 55 shore C vinyl acetate midsole has been suggested as an average value for typical running shoes. 16,23 Prior to the running test, all participants warmed up on a runway at a self-selected speed for 5 minutes and performed standardized lower limb stretching exercises, which were prescribed by researchers. They then performed 3 "qualified" overground running trials over an indoor 45-m tartan runway (Mondo; Mondo S.p.A.) at 4 different speeds (3, 4, 5, and 6 m/s) 17,24 and wearing 2 different shoes (polyurethane elastomer and vinyl acetate). ...
Article
The purpose of this study was to explore the immediate effects of running speed and midsole type on foot loading during heel–toe running. Fifteen healthy male college students were required to complete 3 running trials on an indoor 45-m tartan runway at 4 different speeds (3, 4, 5, and 6 m/s) using 2 different running footwear types (engineering thermoplastic polyurethane elastomer, polyurethane elastomer; and ethylene vinyl acetate, vinyl acetate). The ground reaction force and plantar pressure data were quantified. Significant speed effects were detected both in ground reaction force and plantar pressure-related data ( P < .05). Vertical average loading rate was significantly less, and time to first peak occurred later for the polyurethane elastomer compared with vinyl acetate footwear ( P < .05). The peak pressure of the heel, medial forefoot, central forefoot, lateral forefoot, and big toe was significantly less when subjects wore a polyurethane elastomer than vinyl acetate footwear ( P < .05). Overall, our results suggested that, compared with the vinyl acetate footwear, the special polyurethane elastomer footwear that is adhered with thousands of polyurethane elastomer granules was effective at reducing the mechanical impact on the foot.
... Clarke et al. [8] studied the effect of different amounts of cushioning on vertical force parameters and found that certain vertical force parameters vary depending upon the footwear used and that these differences can be measured by a force platform. Some researchers investigated the influence of midsole hardness on both impact forces and rearfoot motion [19]. Hennig et al. [20] let subjects rate perception of cushioning during running on a treadmill with three different footwear constructions of varying midsole hardness. ...
Article
Vibration is a common phenomenon in people’s daily life. As the main bearing part of the human body, the foot can cushion the impact and shock of external force, and alleviate the influence of external vibration on the human body. Footwear with different structures and materials could cause kinematic, kinetic and biomechanical changes in the foot and leg. It is necessary to evaluate the effects of various footwear on the foot. In this paper, a method based on the vibration cushion characteristics of shoes is proposed to discuss the effect of shoes on feet. First of all, the modal test of the common sole was carried out in this paper, and the acceleration vibration level difference of the sole was obtained. Then, based on the finite element method, the power flow method was used to analyze the soles under different gait patterns. Finally, the vibration analysis of the soles filled with different porous structures was carried out by power flow method. The results show that the vibration level difference and power flow method can be used to study the vibration behavior of vibrating body from the aspects of structure and energy accurately and effectively, and the soles filled with triangular and quadrilateral porous structure have better damping performance. This method can be used to further study the biomechanical effect of the sole on foot and as a reference for shoe design.
... Based on previous literature (Kulmala et al., 2018;Malisoux et al., 2021), we propose two main hypotheses: we hypothesised that lower VIPF, and vertical loading rate would be observed in the Stiff shoe version when compared with the Soft shoe version. Furthermore, given that maximal rearfoot eversion velocity has previously been shown to be greater in running shoes with softer midsole (De Wit, De Clercq, & Lenoir, 1995;MacLean, Davis, & Hamill, 2009), we also hypothesised that ankle eversion maximal velocity would be lower in the stiffer shoe version. We do not advance any hypotheses regarding the other biomechanical variables examined. ...
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In a recent randomized trial investigating running shoe cushioning, injury risk was greater in recreational runners who trained in the shoe version with greater cushioning stiffness (Stiff) compared to those using the Soft version. However, vertical impact peak force (VIPF) was lower in the Stiff version. To investigate further the mechanisms involved in the protective effect of greater cushioning, the present study used an intra-subject design and analysed the differences in running kinematics and kinetics between the Stiff and Soft shoe versions on a subsample of 41 runners from the previous trial. Data were recorded in the two shoe conditions using an instrumented treadmill at 10 km.h⁻¹. VIPF was confirmed to be lower in the Stiff version compared to the Soft version (1.39 ± 0.25 vs. 1.50 ± 0.25 BW, respectively; p = 0.009, d = 0.42), but not difference was observed in vertical loading rate (p = 0.255 and 0.897 for vertical average and instantaneous loading rate, respectively). Ankle eversion maximal velocity was not different (p = 0.099), but the Stiff version induced greater ankle negative work (-0.55 ± 0.09 vs. -0.52 ± 0.10 J.kg⁻¹; p = 0.009, d = 0.32), maximal ankle negative power (-7.21 ± 1.90 vs. -6.96 ± 1.92 W.kg⁻¹; p = 0.037, d = 0.13) and maximal hip extension moment (1.25 ± 0.32 vs.1.18 ± 0.30 N.m.kg⁻¹; p = 0.009, d = 0.22). Our results suggest that the Stiff shoe version is related to increased mechanical burden for the musculoskeletal system, especially around the ankle joint. Trial registration: ClinicalTrials.gov identifier: NCT03115437..
... Similarly, the external loading rate was significantly higher in BR than in SR (De et al., 1994;Komi et al., 1987;Lees, 1988). More compliant shoe cushioning has been found to delay the time at which the tFP occurs and hence reduced the overall loading rate, whereas the magnitude of the impact force was unaffected (Heidenfelder et al., 2010;Wit et al., 2010). In addition, a meta-analysis reported a significant relationship between vertical load rates and tibial stress fractures in RFS runners (Zadpoor and Nikooyan, 2011). ...
Article
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This study aimed to explore the effects of strike patterns and shoe conditions on foot loading during running. Twelve male runners were required to run under shoe (SR) and barefoot conditions (BR) with forefoot (FFS) and rearfoot strike patterns (RFS). Kistler force plates and the Medilogic insole plantar pressure system were used to collect kinetic data. SR with RFS significantly reduced the maximum loading rate, whereas SR with FFS significantly increased the maximum push-off force compared to BR. Plantar pressure variables were more influenced by the strike patterns (15 out of 18 variables) than shoe conditions (7 out of 18 variables). The peak pressure of midfoot and heel regions was significantly increased in RFS, but appeared in a later time compared to FFS. The influence of strike patterns on running, particularly on plantar pressure characteristics, was more significant than that of shoe conditions. Heel-toe running caused a significant impact force on the heel, whereas wearing cushioned shoes significantly reduced the maximum loading rate. FFS running can prevent the impact caused by RFS. However, peak plantar pressure was centered at the forefoot for a long period, thereby inducing a potential risk of injury in the metatarsus/phalanx.
... However, because tissues are viscoelastic, the rate at which these tissues are loaded during the pitch is also important. 1,7,8,15 Loading rate, a modifiable risk factor, is a measure of the rate of stress application and is indicative of increased injury susceptibility and tissue degradation. 1,19,26,27,35 Therefore, not accounting for loading rate in pitching injury risk research may result in leaving out a critical risk factor in identifying at-risk baseball pitchers. ...
Article
Background In the throwing elbow, increased elbow torque has been correlated with increased injury risk. Additional insight into the relationships between anthropometric factors and elbow joint loading is warranted. Purpose To investigate the relationship among physical limb length characteristics, elbow kinetics, and elbow kinematics in youth baseball pitchers and to examine the relationship between elbow varus loading rate and elbow kinetics. Design Descriptive laboratory study. Methods A total of 27 male youth baseball pitchers participated (mean ± SD: age, 15.8 ± 2.7 years; height, 176.3 ± 13.0 cm; weight, 71.7 ± 16.4 kg). Upper arm (UA) and forearm (FA) lengths were measured using a moveable sensor to digitize bony landmarks. Kinematic data were collected at 240 Hz using an electromagnetic tracking system. Participants threw 3 fastballs to a catcher at a regulation distance (60 ft 6 in), and the fastest velocity trial was used for analysis. Linear regression was used to determine the relationship among limb length characteristics, elbow kinetics, and elbow kinematics after accounting for the effects of body weight and height. Results Pitchers with longer UA length experienced increased maximum elbow varus torque ( P = .005) and maximum net elbow force ( P = .001). Pitchers with an increased forearm to UA ratio had decreased elbow compression force ( P < .001) and exhibited a more flexed elbow at foot contact ( P = .001). Pitchers with greater maximum loading rates experienced greater elbow varus torque ( P = .002). Conclusion In youth baseball pitchers, longer UA length and greater loading rate increase varus torque about the elbow during a fastball pitch. Clinical Relevance Longer UA length and greater loading rate may place pitchers at risk of injury because of their relationship with kinetic values.
... The cumulative load applied to the musculoskeletal system resulting from several thousand steps taken during each training session may lead to an overuse injury, especially if inadequate recovery is provided between stress applications (Hreljac, 2004). For decades, it has been assumed that some running-related injuries are typically associated with the landing phase (e.g., stress fracture, tendinopathy), because of the stress resulting from the collision between the body and the ground (Cavanagh and Lafortune, 1980;Bobbert et al., 1991;Wit et al., 1995). The main arguments are that forces observed during distance running are 1.5-2 times larger than those occurring in walking, a rapid increase in force immediately follows initial contact, and a runner covering 20 km per week will cumulate more than 10,000 impacts on each leg over a seven-day period. ...
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These studies show that I applied to functional insole (a specific S company) for minimizing shocks and sprain people's ankle arising from running. How to an effect on human body which studied a kinematics and kinetics from 10 college students during experiments. This study imposes several conditions by barefoot, normal running shoes and put functional insole shoes ran under average meter per second by motion analysis, ground reaction force and electromyography that used to specific A company. First of all, Motion analysis was caused by Achilles tendon angle, Angle of the lower leg, Angle of the knee, Initial sole angle and Barefoot angle. Second, Contact time, Vertical impact force peak timing, Vertical active force and Active force timing, and Maximum loading rate under impulse of first 20 percent and Value of total impulse caused Ground reaction force. Third. The tendon fo Quadriceps femoris, Biceps femoris, Tibialis anterior and gastronemius medials caused. electromyography. 1. Ground reaction force also showed that statically approximates other results from impact peak timing (p.001), Maximum loading rate(p
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Purpose The purpose of this study was to investigate the effect of midsole hardness on gait mechanisms by wearing a backpack. Methods Ten healthy adult males(age:23.20±1.33yrs, heights: 1.72±0.03cm, weights: 67.60±5.95kg) participated in this study. Subjects walked at a speed of 1.5m/s in an 8m section wearing randomly selected midsole hardness (Soft, Medium, Hard) shoes and backpack (30% of body weight). For measurement of body movement, 10 infrared cameras (Vicon motion capture system, UK) and force plate (AMTI, ORG-6, US) were used. Results First, in the shock phenomenon change, the ground contact time was longer when wearing a backpack. Second, in the shock absorption strategy, the pack plantarflexion velocity at the ankle joint was faster in Hard than Soft, and the pack dorsiflexion moment decreased when wearing a backpack (p<.05). Also, the pack extension moment of the knee increased significantly when wearing a backpack. Fourth, in the mechanical negative work, the ankle joint performed less work than the medium soft, and the knee joint increased as the backpack was worn (p<.05). Conclusion As a result of this study, the difference in the hardness of the midsole used in this study does not seem to affect the biomechanical movement of gait even when wearing a backpack. In future studies, it is necessary to investigate the effect of the midsole through the presence or absence of shoes or inducing muscle fatigue.
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To design functionally adequate footwear, an understanding of the dynamic biomechanical behaviour of the foot during locomotion is necessary. Thus, this chapter characterizes biomechanical aspects of the foot during gait. moreover, it provides the fundamentals by reviewing the gait phases and providing a closer look at resulting ground reaction forces, pressure distributions and kinematics, as well as dynamic morphologies of the foot during gait. A brief overview of current biomechanical measurement devices and measurement variables is also provided. finally, present and future directions of footwear research are discussed, considering particularly the recent insights of biomechanical research on gait.
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هدف این مطالعه، بررسی ارتباط بین حداکثر گشتاور مفاصل اندام تحتانی با حداکثر نیروی عکس‌العملزمین در تکلیف فرود تک‌پا بود. 30 ورزشکار به‌صورت داوطلبانه در این مطالعه شرکت کردند. متغیرهای کینتیکی و کینماتیکی اندام تحتانی طی فرود تک‌پا، توسط دستگاه تحلیل حرکت و صفحه‌نیرو جمع آوری شدند. نتایج آماری نشان داد که ارتباط معناداری بین حداکثر گشتاور فلکشن، اداکشن و روتشین هیپ و مفصل مچ پا با حداکثر نیروی عکس‌العملزمینوجود ندارد؛ اما ارتباط معنا‌داری بین حداکثر گشتاور مفصل زانو و مفصل تحت‌قاپی با حداکثر نیروی عکس‌العمل عمودی زمین وجود دارد. یافته‌ها نشان داد که بین نیروی عکس‌العمل عمودی زمین و گشتاور زانو و مفصل تحت‌قاپی ارتباط وجود دارد؛ بنابراین، هرچه میزان نیروی عکس‌العمل عمودی زمین بیشتر باشد، میزان باری که به این دو مفصل وارد می‌شود بیشتر است و می‌تواند این دو مفصل را درمعرض‌ آسیب بیشتر قرار دهد.
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In brief: This retrospective survey of the clinical records of 1,650 patients seen from 1978 to 1980 identified 1,819 injuries. Almost 60% of the patients were men, but women under age 30 had the greatest risk of overuse running injuries. The knee was the most commonly injured site, and patellofemoral pain syndrome was the most common injury. Most patients had moderate to severe degrees of varus alignment and subsequent overpronation. Because certain injuries were more frequent in one sex or the other, the authors say future studies should differentiate injuries by sex.
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The purpose of this study was to identify the kinematic characteristics of bilateral rearfoot asymmetry during heel–toe running under two experimental conditions: worn (broken-in) running shoes and new (standardized) running shoes. High-speed cinematography (150 fps) was used to film the lower limbs of four male runners in the frontal plane while running on a treadmill at their training pace. Six successive footfalls were analyzed for each subject and selected kinematical variables of the rearfoot function were calculated. Significant asymmetries were found in lower leg angle and Achilles tendon angle at touchdown and at maximum pronation. Total pronation and rearfoot angle were almost symmetric. The angular displacement graphs for the shank and foot revealed a distinct overall asymmetry between the lower limbs in both conditions. The mean values of the kinematical asymmetries were appreciably higher in the new shoe condition. It is proposed that the degree of these asymmetries is subject to changes due t...
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This study investigated the phenomenon of kinematic asymmetry of the lower limbs in distance runners. The subjects, 29 male distance runners, were recorded by high-speed filming while running on a motor driven treadmill under two experimental conditions (with running shoes and barefoot). Twelve selected kinematic variables were subjected to multivariate statistical analysis. It was demonstrated that the lower limbs of distance runners possess a multifaceted kinematic asymmetry for touchdown and foot contact as well as for the entire phase of foot support of the running stride. Significant kinematic asymmetries were found in the lower leg angle, rearfoot angle, mediolateral velocity of the foot, and in some temporal variables. Contemporary running shoes seem to significantly change the degree of rearfoot control asymmetry observed in normal barefoot running. The findings of the present study confirm previous data suggesting that the phenomenon of kinematic asymmetry in runners is warranted.
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Shock attenuation of the impact peak and overpronation are both considered important in running shoe design. A number of investigations indicate that both of these factors are related to various running injuries. These indications are mostly empirical or based on statistics and often show a lack of arguments to relate external measurements to internal loading of joints or muscles. The purpose of this paper is to present some relationships between impact peak, pronation, and forces at the subtalar joint and on muscles (which are in tension in pronation) during touchdown in rearfoot running. The calculations show that the material properties of the shoe sole (altered from Shore A20 to A50) largely influence the rearfoot movements during touchdown (increase in pronation velocity from 7 to 25 rad/s) and increase to some extent the muscle forces on the medial side (600 to 850 N) of the subtalar joint. In comparison, the impact peak (1550 to 1600 N) and the ankle joint forces (2500 to 2700 N) change very little...
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Estimating derivatives from noisy displacement data is a notoriously ill-posed problem in signal processing and biomechanics. Following the work of Wood and Jennings (1978) and Hatze (1979, 1981), the present paper describes the use of optimally regularized, natural quintic splines for estimating smoothed positions, velocities, and accelerations from equidistantly sampled, noisy position measurements. It appears that the nature of the boundary conditions of the data is of some importance, since various algorithms used hitherto result in artefacts throughout the data if the true derivatives at the record ends differ significantly from zero. Natural quintic splines do not suffer from this disadvantage below the third derivative.The ill-posed character of movement analysis has some interesting implications for movement synthesis and optimization, similar to the indeterminacy of muscular co-contraction from merely external, biomechanical measurements.
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The purpose of this study was to investigate the influence of midsole hardness and running velocity on external impact forces in heel-toe running. Fourteen subjects were assessed with a force platform and high speed film while running at speeds of 3, 4, 5 and 6 m s-1. The result showed that running velocity does influence external impact force peaks (linear connection) and that midsole hardness does not influence magnitude and loading rate of the external vertical impact forces. Changes in kinematic and kinetic data can be used to explain this result mechanically. However, the neuromuscular control mechanisms to keep external impact forces constant are not known.
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The study of sports injuries has grown with the increase in importance of sport as a leisure-time activity. The origin of many sports injuries is assumed to be mechanical, with the forces and/or stresses acting on one element of the human locomotor system exceeding the critical limits. This article presents some biomechanical considerations on the mechanical aspect of the aetiology, reduction and treatment of sport injuries with special emphasis on the lower extremities. Forces acting on the locomotor system have a magnitude, a point of application and a direction. Both magnitude and geometry (point of application and direction) are important in load analysis. However, the geometrical aspect of externally acting forces is an extremely important aspect, especially with respect to reduction of load in practical situations. Load analysis is usually performed with force transducers and optical instruments in order to quantify magnitude and geometry. Two possible approaches to load analysis are discussed. One approach works with the critical limits of biomaterials. This approach shows that the local stresses for cartilage, tendon and bone are in the order of 10 to 20% of the critical limit for normal daily activities, such as walking. The second approach deals with strategies to reduce load, assuming that it is usually too high in sports activities. The nature of playing surfaces and shoes are revealed as important possibilities for load reduction.
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Control of the amount and/or rate of pronation of the foot which occurs during distance running has been cited as an important consideration for runners when selecting a running shoe. In this study, high-speed movie film was taken from the rear while 10 subjects ran on a treadmill at a pace of 3.8 m X s-1. These subjects wore 36 different shoes in combinations of three midsole hardnesses, three heel flares, and four heel heights. The film data were digitized and used to determine the eversion or inversion of the heel relative to the lower leg throughout foot contact. Because eversion of the foot is a component of pronation it was used as a predictor of how much pronation was occurring. It was found that shoes with soft midsoles (25 durometer, Shore A scale) allowed significantly more maximum pronation (MP) and total rearfoot movement (TRM) than shoes with either medium (35 durometer) or hard (45 durometer) midsoles. Shoes with 0 degrees heel flare allowed significantly more MP and TRM than shoes with either 15 degrees or 30 degrees heel flares. Heel height was found to have no significant effect on either MP or TRM. These data provide guidelines for the construction of running shoes designed to limit rearfoot movement.
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Ground reaction forces and center of pressure (C of P) patterns were studied in 17 subjects running at 4.5 ms−1. The subjects were classified as rearfoot or midfoot strikers according to the location of the C of P at the time of first contact between foot and ground. The C of P path in the rearfoot group showed a continuous anterior movement during support while the C of P in most of the midfoot group migrated posteriorly during the first 20 ms of the support phase. Variability in both groups was most marked during early support. The mean peak to peak force components were 3 BW, 1 BW and 0.3 BW in the vertical, anteroposterior and mediolateral directions respectively. Consistent differences between groups were noted in all three components, but individual differences within a given group were also considerable. The C of P patterns are presented in conjunction with ground reaction force data, and the implications of the results in the areas of running mechanics, shoe design and sports injury are discussed.