Rearfoot Strike Pattern Research Articles

Conversion to a rearfoot strike pattern during running for prevention of recurrent calf strains: A case report

BackgroundRunning-related injuries are prevalent musculoskeletal complaints in the United States military. Although, run retraining is an extensively researched method for reducing pain and improving function in runners, its clinical utility remains low. Case descriptionThe patient had a seven-year history of recurrent right calf strains. Prior conventional physical therapy failed to resolve symptoms. A biomechanical running analysis revealed a right forefoot strike during running. The patient underwent run retraining that included real-time visual feedback and a faded feedback strategy focused on converting foot strike pattern to rearfoot. Running mechanics were reassessed post-training, and at one and six months post-training. OutcomesFoot strike pattern was successfully converted to rearfoot strike and was maintained up to six months post-training. Reductions in peak ankle dorsiflexion moment and dorsiflexion velocity were noted up to six months post-training. Self-reported function also improved by 20–30% and no calf strains were reported up to six months post-training. DiscussionThis case report details the clinical reasoning and evidence-informed interventions involved in treatment of a patient with chronic calf strains. The management strategy was intended to reduce eccentric calf demands, which allowed the patient to tolerate increased running frequency without any further episodes of calf strains up to six months post-training.

Does habitual rear-foot strike pattern with modern running shoes affect the muscle strength of the longitudinal arch?

Does habitual rear-foot strike pattern with modern running shoes affect the muscle strength of the longitudinal arch?

Regular changes in foot strike pattern during prolonged downhill running do not influence neuromuscular, energetics, or biomechanical parameters

Research has suggested that a high variability in foot strike pattern during downhill running is associated with lower neuromuscular fatigue of the plantar flexors (PF). Given the popularity of trail running, we designed an intervention study to investigate whether a strategy with regular changes in foot strike pattern during downhill running could reduce the extent of fatigue on neuromuscular, energetics and biomechanical parameters as well as increase an uphill time-to-exhaustion trial (TTE) performance. Fourteen experienced trail runners completed two interventional conditions (separated by 15 days) in a pseudo-randomised and counter-balanced order that consisted of 2.5-h of treadmill graded running with (switch condition) or without (control condition) a change between fore- and rear-foot strike pattern every 30 s during the downhill sections. Pre and Post, neuromuscular tests were performed to assess PF central and peripheral fatigue. Energy cost of running was assessed using an indirect calorimetry system and biomechanical gait parameters were acquired with an instrumented treadmill. TTE was performed after both the graded running conditions. There were not significant condition × time interactions (p ≥ .085) for any of the variables considered, and TTE was not different between the two conditions (p = .755). A deliberate strategy to alternate between foot strike patterns did not reduce the extent of fatigue during prolonged graded running. We suggest that it is not the ability to switch between foot strike patterns that minimises fatigue; rather the ability to adapt foot strike pattern to the terrain and therefore a better running technique.

Forefoot strike, rear foot strike or running shoes. Does it matter?

The main aim of this article is to provide some insight into evidence-based data in running. The prevalence of a rearfoot strike (RFS) pattern is much more usual than a forefoot strike (FFS) even among elite distance runners. There has been significant pressure on runners to change their running style from RFS to FFS in recent times. Usually, this has been justified by the statement that FFS relates to a lower injury rate. Recent studies have shown however, that this statement is probably not true. Different types of strike pattern have an influence on loading different structures of the lower limbs, but the total incidence of running related injury is the same regardless of the type of foot strike pattern.We want to provide not only an objective view on running technique but also an evidence-based view on the choice of running shoes. There are many recommendations to consider when choosing running shoes, especially in running stores, but only a few of them are supported by research.This article is not a meta-analysis but it provides some evidence based information about running styles and running shoes.

Consolidation of the atypical rearfoot strike pattern in distance runners and linkage to tibial shocks

Shod rearfoot striking can be subdivided into typical and atypical using plantar pressures (Breine, Malcolm, Frederick, & De Clercq, 2014). The atypical pattern makes an initial rearfoot contact, f...

Comparison of lower limb muscle architecture and geometry in distance runners with rearfoot and forefoot strike pattern

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

Initial contact and toe off event identification for rearfoot and non-rearfoot strike pattern treadmill running at different speeds

The purpose of this study was to determine the validity of kinematic based initial contact (IC) and toe-off (TO) identification algorithms for rearfoot and non-rearfoot runners across a broad range of treadmill running speeds. 14 healthy active participants completed six 20–60 s treadmill running trials at 6 speeds: 2.24, 2.68, 3.13, 3.58, 4.02, and 4.48 ms−1. 3D kinematic data were collected for the last 20 s of each trial. Force plates (FP) were used as the gold standard to determine ICFP and TOFP for each step. Three algorithms for finding IC, ICMilner, ICAlvim, ICAlvim-mod, and one algorithm for finding toe off, TOFellin, were chosen for analysis. Root mean square errors (RMSE) and difference scores with 95% confidence intervals were computed for IC, TO and stance time (ST). ICAlvim RMSE ranged from 0.175 to 0.219 s. STAlvim RMSE ranged from 0.168 to 0.216 s. ICAlvim-mod RMSE ranged from 0.105 to 0.131 s. STAlvim-mod RMSE ranged from 0.108 to 0.129 s. ICMilner RMSE ranged 0.012 to 0.015 s. STMilner RMSE ranged 0.019 to 0.024 s. ICMilner accuracy was inversely related to speed. ICMilner corrected with a linear regression equation reduced differences to- 0.006 ± 0.012 s with 86% of foot strikes identified within 20 ms and 58% with 10 ms. TOFellin RMSE ranged from 0.012 to 0.016 s. ICMilner adjusted for speed and TOFellin can be used to predict IC and TO within a broad range of treadmill running speeds (2.24–4.48 ms−1) and for rearfoot and non-rearfoot strikers.

Is Cadence Related to Leg Length and Load Rate?

Increasing cadence is often recommended to reduce load rate and to lower injury risk. However, habitual cadence was recently shown to be unrelated to load rate. Cadence is likely influenced by leg length. If so, then cadence may be related to load rate when it is normalized to leg length. To examine the relationship between cadence and leg length in both injured and uninjured runners with a rearfoot strike pattern. We hypothesized that increased leg length would be associated with lower cadence. We also evaluated the relationship between cadence normalized to leg length and the vertical average load rate (VALR), expecting that as cadence normalized to leg length increased, VALR would decrease. In this cross-sectional cohort, laboratory-based study, 40 uninjured and 42 injured recreational runners with a rearfoot strike pattern were measured at self-selected speeds. The relationship of cadence to leg length was measured between groups by injury status. A secondary analysis evaluated the relationship between cadence normalized to leg length and VALR. The data were analyzed using a multiple linear regression, with injury status as a covariate. Alpha was set to .05. Accounting for injury status, leg length had a moderate negative association with cadence (P<.001, r = 0.449, standardized β = - 0.443). There were no associations of VALR with cadence normalized to leg length by injury status or across participants. Lower cadence was observed in recreational runners with longer legs, regardless of injury status. However, cadence was not related to load rate when normalized to leg length. J Orthop Sports Phys Ther 2019;49(4):280-283. doi:10.2519/jospt.2019.8420.

Lower extremity stiffness when running in minimalist, traditional, and ultra-cushioning shoes

Differences in running mechanics between minimalist (MIN) and traditional (TRAD) running shoes have been the subject of much research in the last decade. More recently, ultra-cushioning (ULTRA) shoes featuring oversized midsoles have emerged and are growing in popularity. However, relatively little is known regarding how ULTRA shoes effect running mechanics. Therefore, the purpose of this study was to compare foot strike, leg stiffness, joint stiffness, and negative joint work when running in MIN, TRAD, and ULTRA shoes. Fifteen recreational runners ran on an instrumented treadmill in each shoe while their whole body kinematics were recorded using a 12-camera motion capture system. Foot strike pattern was quantified using the strike index (SI) and foot strike angle (FSA). Leg stiffness was calculated using a spring-mass model. Joint stiffness was calculated as change in joint moment relative to change in joint angle during the absorption period. Negative joint work was calculated by integrating the negative portion of the joint power curve. Differences between shoes were evaluated using a one-way repeated measures ANOVA. Results showed there were no differences between MIN and TRAD shoes for any of the dependent variables. In the ULTRA shoe, participants used a more pronounced rearfoot strike pattern. There were no differences in leg stiffness between shoes. Compared to the MIN and TRAD shoes, in the ULTRA shoes the ankle was stiffer and performed less negative work while the knee and hip were less stiff and performed more negative work. These findings suggest a reorganization of the neuromuscular control of the limb when running in ULTRA compared to MIN or TRAD shoes. This reorganization may have implications for running performance or injury prevention.

Habitual foot strike pattern does not affect simulated triceps surae muscle metabolic energy consumption during running.

Foot strike pattern affects ankle joint work and triceps surae muscle-tendon dynamics during running. Whether these changes in muscle-tendon dynamics also affect triceps surae muscle energy consumption is still unknown. In addition, as the triceps surae muscle accounts for a substantial amount of the whole-body metabolic energy consumption, changes in triceps surae energy consumption may affect whole-body metabolic energy consumption. However, direct measurements of muscle metabolic energy consumption during dynamic movements is difficult. Model-based approaches can be used to estimate individual muscle and whole-body metabolic energy consumption based on Hill type muscle models. In this study, we use an integrated experimental and dynamic optimization approach to compute muscle states (muscle forces, lengths, velocities, excitations and activations) of 10 habitual midfoot/forefoot striking and nine habitual rearfoot striking runners while running at 10 and 14 km h-1 The Achilles tendon stiffness of the musculoskeletal model was adapted to fit experimental ultrasound data of the gastrocnemius medialis muscle during ground contact. Next, we calculated triceps surae muscle and whole-body metabolic energy consumption using four different metabolic energy models provided in the literature. Neither triceps surae metabolic energy consumption (P>0.35) nor whole-body metabolic energy consumption (P>0.14) was different between foot strike patterns, regardless of the energy model used or running speed tested. Our results provide new evidence that midfoot/forefoot and rearfoot strike patterns are metabolically equivalent.

Running gait pattern recognition based on cross-correlation analysis of single acceleration sensor.

As people pay more attention to physical fitness and health keeping, running becomes the first choice for daily sport. However, due to the lack of scientific management and guidance, unreasonable running sometimes has a negative impact on health. The foot strike pattern has a great impact on the knee joint of the runner during running. Therefore, it is important for runners to monitor and record their running gait, so as to customize more appropriate training programs. Through cross-correlation analysis on two axial signals of the acceleration sensor, two common running landing gait patterns, the forefoot strike pattern and the rearfoot strike pattern, can be identified and distinguished. Based on the theoretical analysis, two running gait pattern recognition experiments were designed and conducted. Experiment results reveal that the method proposed can effectively characterize the two running gait patterns and shows a good universality and generalization ability among different subjects.

Patellofemoral joint stress measured across three different running techniques

BackgroundPatellofemoral pain (PFP) is the most common running-related injury. It has been shown in previous studies that gait retraining may have a beneficial effect on patellofemoral joint stress (PFJS). Research questionIs there a reduction of PFJS across 4 running conditions: 1. runner’s typical rearfoot strike pattern, 2. forefoot landing, 3. step rate increase by 10% and 4. forward trunk lean? MethodsNineteen healthy runners (28.05 ± 5.03 years; 26.58 ± 8.85 km/week, 6.00 ± 4.51 years of running experience) completed one running trial for each condition, at the same subject-specific comfortable speed on a treadmill. Kinetic and kinematic data were collected and measures of hip, knee and ankle joint moments and PFJS were calculated. ResultsCompared to rearfoot strike condition, peak PFJS and PFJS-time integral per step were significantly (P < 0.01) lower during forefoot landing and step rate increase conditions. PFJS per kilometer was significantly reduced for forefoot landing (17.01%; P < 0.01) and increased step rate (12.90%; P = 0.003). Forward trunk lean technique showed no significant differences in peak PFJS (P = 0.187), PFJS-time integral per step (P = 0.815) and PFJS per kilometer (P = 0.077) compared to rearfoot strike pattern. InterpretationThe comparison between techniques revealed greater reductions on PFJS by forefoot landing, followed by 10% step rate increase condition. These changes were the result of different lower limb movement strategies across the 2 running conditions. We conclude that compared to a rearfoot strike pattern, both a forefoot landing and step rate increase result in lower cumulative PFJS joint stress in healthy runners, with the forefoot landing being the most effective. These running technique modifications could be recommended to reduce PFJS loads and may have implications for PFP prevention.

The effects of habitual foot strike patterns on Achilles tendon loading in female runners

BackgroundFemale runners that habitually use a forefoot/midfoot strike pattern (non-rearfoot runners) may be at greater risk for Achilles tendinopathy compared to runners that habitually use a rearfoot strike pattern. Differences in Achilles tendon loading between non-rearfoot and rearfoot strike runners may be a contributing factor. Research QuestionOur purpose was to determine if there were differences in Achilles tendon loading and cross-sectional area between female habitual rearfoot and non-rearfoot strike runners. MethodsThirty-five female runners participated in this cross-sectional study (17 rearfoot strike runners, 18 non-rearfoot strike runners). Ultrasound images of the Achilles tendon were used to measure cross-sectional area. Kinematic and kinetic data were collected at a set running speed and used in a muscloskeletal model to calculate Achilles tendon force. Achilles tendon stress was determined from specific Achilles tendon cross-sectional area. Principal components (PC) analysis was performed to identify/characterize the primary sources of variability in the Achilles tendon stress time series. The PC scores and cross-sectional area where compared using independent t-tests. ResultsPC 1 reflected variability in the Achilles tendon stress magnitude from 25 to 100% of stance, PC 2 reflected timing variability, and PC 3 reflected variability in the magnitude during early stance (0–25%). The non-rearfoot strike runners demonstrated higher PC scores for PC 1 and PC 3 compared to the rearfoot strike runners. This reflected greater Achilles tendon stress during mid/late stance (PC 1) and early stance (PC 3) for the non-rearfoot strike runners. For PC 2, there was a trend toward higher PC scores in the non-rearfoot strike runners. Achilles tendon cross-sectional area for the rearfoot and non-rearfoot strike runners were not different. SignificanceHabitual non-rearfoot strike runners did not have greater cross-sectional area despite higher Achilles tendon loading, which may pose a higher risk for Achilles tendinopathy.

Biomechanical Performance of Habitually Barefoot and Shod Runners during Barefoot Jogging and Running

The purpose of this study was to evaluate the biomechanical performances, running stability of habitually barefoot (BR) and shod runners (SR) during barefoot jogging and running. Ten healthy male subjects, 5 habitually shod runners and 5 habitually barefoot runners, from two different ethnics participated in this study. Subjects performed jogging (2m/s) and running (4m/s) along a 10-m runway. Three-dimensional lower-limb kinematics, ground reaction force, center of pressure (COP) and contact time (CT), were collected during testing. During jogging and running, all participants adopted rear-foot strike pattern, SR had larger VALR. SR showed significantly larger lower-limb range of motion (ROM) in sagittal plane, significantly larger hip abduction and opposite knee ROM in frontal plane, as well as significantly larger ankle internal rotation in horizontal plane. All participants’ CT showed decreased trend with running speed up; and SR was significantly longer than BR; BR and SR in COP showed different trajectories, especially forefoot and rearfoot areas. Habitually barefoot and shod runner from different ethnics still exist significant differences in lower-extremity ROM; and different foot morphological of participants is an important influential factor for these variations.

Forefoot Striking Is More Effective in Reducing Loadrates than Increasing Cadence in Runners

Category: Sports Introduction/Purpose: Vertical impact forces are highly influenced by the way the foot contacts the ground. These impact forces are associated with high loading rates which have been related to running injuries. As a result, clinicians have begun to use gait retraining interventions to reduce loadrates and prevent future impact-related injuries. Two types of gait retraining techniques have been promoted to reduce excessive running impacts. The first involves increasing cadence (CAD), or number of steps per minute, by 5-10%, thereby reducing stride length. The second type of gait retraining involves landing on the ball of the foot at ground contact, or using a forefoot strike (FFS). Both of these gait-retraining styles have been reported to reduce impacts, but they have not been compared with each other. Methods: 33 healthy runners (9M, 24F), running 5-15 mpw, with a rearfoot strike pattern with cadence &lt; 170 steps/min were recruited. Subjects were randomly allocated to either FFS or CAD retraining. All subjects underwent an 8-session gait retraining program (over 2-3 wks) with auditory feedback on a treadmill. The CAD group ran to a digital metronome to increase cadence by 7.5%. The FFS group wore a wireless accelerometer that provided an auditory signal on footstrike pattern. A gait analysis was conducted at baseline, 1 wk, 1 month, and 6 months. Variables included vertical average and instantaneous load rates (VALR, VILR). A 2 x 4 repeated measures ANOVA was used to compare differences within and between the CAD and FFS groups at baseline, 1 week, 1 month and 6 months post retraining. For variables with significant interactions, simple main effects of group, as well as time were further explored using one-way ANOVA Results: There were significant interaction effects of time*group for VALR (p= 0.001), VILR (p=0.001) and foot angle (p&lt; 0.001), but not cadence. For the simple main effects for the CAD group, VALR reduced by 14%, 7% and 16% at 1 week, 1 month, and 6 months post gait retraining respectively, compared with baseline (Figure 1). However, these reductions were not significant. For the FFS group, VALR was significantly reduced by 50%, 51% and 51% at 1 week, 1 month, and 6 months post gait retraining respectively. Interestingly, both the CAD and FFS groups increased cadence by similar amounts. Conclusion: Transitioning to a FFS pattern is significantly more effective than increasing CAD when reducing vertical loadrate (both VALR and VILR) is the goal. These changes persisted out to 6 months post gait retraining, suggesting permanence of the new pattern.

No immediate effects of highly cushioned shoes on basic running biomechanics

The aim of the study was to investigate the effects of highly cushioned shoes on running biomechanics. Sixteen recreational runners (8 males, 8 females) participated and ran at a self-selected pace across the force platform in the research laboratory wearing either the standard or highly cushioned shoes, in randomized order. Impact peak (IP), loading rate to IP (LR), active peak (AP), contact time (CT), strike index (SI), running velocity, and knee and ankle kinematics at initial contact (IC) and AP were recorded during the running trials. Overall, there was no effect of footwear on IP, LR, AP, CT and velocity (p&amp;gt;.05) with small effect sizes (ES&amp;lt;0.2). The highly cushioned shoes resulted in a more anterior foot strike pattern, based on the slightly higher SI (p=.03, ES=0.5), although the runners demonstrated a rearfoot strike pattern regardless of shoe condition. No kinematic differences were observed at IC or AP, across shoe conditions (p&amp;gt;.05). Our results indicate that the highly cushioned shoes did not show immediate changes in running biomechanics.

Comparison of Biomechanical Characteristics on Barefoot Running and Shod Running

Background Compared with the rearfoot strike pattern of shod running, barefoot running with a forefoot strike pattern will change the kinematics and kinetic parameters. This paper analyses the biomechanical differences between barefoot running and shod running and aims to provide a reference for barefoot training and the prevention of sports injury. Methods Three-dimensional force plate test and three-dimensional video analysis. Results Kinetic characteristics: The F-t curve by the force plate test shows that barefoot running has a smooth curve with a single peak while the F-t curve of shod running has a double peak on the vertical direction curve. The maximum ground reaction force in the vertical direction of barefoot running is significantly less than shod running. Kinematics characteristics: Compared with shod running, barefoot running has a faster step frequency, a shorter stride length, a shorter foot-to-ground contact time. The smaller stride length means barefoot running has a bigger ankle plantar flexion, which shows barefoot running can reduce sports injuries.

Three-Dimensional Biomechanical Analysis of Rearfoot and Forefoot Running.

Background:In the running community, a forefoot strike (FFS) pattern is increasingly preferred compared with a rearfoot strike (RFS) pattern. However, it has not been fully understood which strike pattern may better reduce adverse joint forces within the different joints of the lower extremity.Purpose:To analyze the 3-dimensional (3D) stress pattern in the ankle, knee, and hip joint in runners with either a FFS or RFS pattern.Study Design:Descriptive laboratory study.Methods:In 22 runners (11 habitual rearfoot strikers, 11 habitual forefoot strikers), RFS and FFS patterns were compared at 3.0 m/s (6.7 mph) on a treadmill with integrated force plates and a 3D motion capture analysis system. This combined analysis allowed characterization of the 3D biomechanical forces differentiated for the ankle, knee, and hip joint. The maximum peak force (MPF) and maximum loading rate (LR) were determined in their 3 ordinal components: vertical, anterior-posterior (AP), and medial-lateral (ML).Results:For both strike patterns, the vertical components of the MPF and LR were significantly greater than their AP or ML components. In the vertical axis, FFS was generally associated with a greater MPF but significantly lower LR in all 3 joints. The AP components of MPF and LR were significantly lower for FFS in the knee joint but significantly greater in the ankle and hip joints. The ML components of MPF and LR tended to be greater for FFS but mostly did not reach a level of significance.Conclusion:FFS and RFS were associated with different 3D stress patterns in the ankle, knee, and hip joint, although there was no global advantage of one strike pattern over the other. The multimodal individual assessment for the different anatomic regions demonstrated that FFS seems favorable for patients with unstable knee joints in the AP axis and RFS may be recommended for runners with unstable ankle joints.Clinical Relevance:Different strike patterns show different 3D stress in joints of the lower extremity. Due to either rehabilitation after injuries or training in running sports, rearfoot or forefoot running should be preferred to prevent further damage or injuries caused by inadequate biomechanical load. Runners with a history of knee joint injuries may benefit from FFS whereas RFS may be favorable for runners with a history of ankle joint injuries.

Immediate and short-term biomechanical adaptation of habitual barefoot runners who start shod running

ABSTRACTThis study investigated the immediate and short-term effects of minimalist shoes (MS) and traditional running shoes (TRS) on vertical loading rates, foot strike pattern and lower limb kinematics in a group of habitual barefoot runners. Twelve habitual barefoot runners were randomly given a pair of MS or TRS and were asked to run with the prescribed shoes for 1 month. Outcome variables were obtained before, immediate after and 1 month after shoe prescription. Average and instantaneous vertical loading rates at the 1-month follow-up were significantly higher than that at the pre-shod session (P < 0.034, η2p > 0.474). Foot strike angle in the TRS group was significantly lower than that in the MS group (P = 0.045, η2p = 0.585). However, there was no significant time nor shoe effect on overstride, knee and ankle excursion (P > 0.061). Habitual barefoot runners appeared to land with a greater impact during shod running and they tended to have a more rearfoot strike pattern while wearing TRS. Lower limb kinematics were comparable before and after shoe prescription. Longer period of follow-up is suggested to further investigate the footwear effect on the running biomechanics in habitual barefoot runners.

CSM 2017 Sports Physical Therapy Section Poster Presentations (Abstracts SPO1–SPO152)

CSM 2017 Sports Physical Therapy Section Poster Presentations (Abstracts SPO1–SPO152)