Minimalist Shoes Research Articles

Modifications in lower leg muscle activation when walking barefoot or in minimalist shoes across different age-groups

Ageing is associated with a decline in muscle strength and impaired sensory mechanisms which contribute to an increased risk of falls. Walking barefooted has been suggested to promote increased muscle strength and improved proprioceptive sensibility through better activation of foot and ankle musculature. Minimalist footwear has been marketed as a method of reaping the suggested benefits of barefoot walking whilst still providing a protective surface. The aim of this study was to investigate if walking barefoot or in minimalist footwear provokes increased muscle activation compared to walking in conventional footwear. Seventy healthy adults (age range 20–87) volunteered for this study. All participants walked along a 7m walking lane five times in four different footwear conditions (barefoot (BF), minimalist shoes (MSH), their own shoes (SH) and control shoes (CON)). Muscle activity of their tibialis anterior (TA), gastrocnemius medialis (GCM) and peroneus longus (PL) were recorded simultaneously and normalised to the BF condition. MSH are intermediate in terms of ankle kinematics and muscle activation patterns. Walking BF or in MSH results in a decrease in TA activity at initial stance due to a flatter foot at contact in comparison to conventional footwear. Walking BF reduces PL activity at initial stance in the young and middle age but not the old. Walking in supportive footwear appears to reduce the balance modulation role of the GCM in the young and middle age but not the old, possibly as a result of slower walking speed when BF.

Effects of shoe drop on running mechanics in women

During the last decade, there has been an increasing enthusiasm in minimalist shoe trend. Consequently, many running shoes companies have promoted a lower drop of their shoes that could cause biome...

The longer-term effects of minimalist running shoes on lower limb structure and function, running performance, and injury risk

The effects of transitioning to minimalist running shoes are a topic of interest for runners and scientists. However, relatively few studies have investigated longer-term effects of running in minimalist shoes. This paper will report preliminary findings from a planned 20-week follow-up of runners who participated in a 6-week randomised controlled trial of minimalist shoes and had successfully transitioned to using minimalist or control shoes for 35% of weekly training. Runners continued to transition to their allocated shoes throughout the planned 20-week follow-up by increasing minimalist or control shoe use by 5% each week. The allocated shoes were used for 100% of weekly running during the final 6 weeks of the follow-up. Training volume, shoe use, running-related pain and injury were monitored weekly. Time trial performance, running economy, stride rate, stride length, shoe comfort, ankle plantar flexor muscle strength, and bone mineral density in the tibia, calcaneus, and metatarsals were assessed at the end of the 20-week follow-up. Early published findings from this trial demonstrate that risk of sustaining a running-related injury increased for heavier runners using minimalist shoes compared to control shoes. Additionally, greater weekly calf, ankle, and shin pain severity were experienced by runners completing high weekly running distance using minimalist shoes compared to control shoes. This paper will expand on these published findings by (1) discussing the longer-term effects of transitioning to minimalist shoes on time trial performance, running economy, muscle strength and bone mineral density, and (2) use a series of example cases from the study to explore potential moderating factors (shoe comfort, running biomechanics, and training volume) that might influence the effects of minimalist shoes on running performance, muscle strength, bone mineral density, pain and injury. The clinical and research implications of the findings from this planned follow-up study and case series investigation will be discussed.

The influence of cadence and shoes on patellofemoral joint kinetics in runners with patellofemoral pain

ObjectivesTo determine the effect of a combination of a minimalist shoe and increased cadence on measures of patellofemoral joint loading during running in individuals with patellofemoral pain. DesignWithin-participant repeated measures with four conditions presented in random order: (1) control shoe at preferred cadence; (2) control shoe with +10% cadence; (3) minimalist shoe at preferred cadence; (4) minimalist shoe with +10% cadence. MethodsFifteen recreational runners with patellofemoral pain ran on an instrumented treadmill while three-dimensional motion capture data were acquired. Peak patellofemoral joint stress, joint reaction force, knee extensor moment and knee joint angle during the stance phase of running were calculated. One-way repeated measures ANOVA was used to compare the control condition (1) to the three experimental conditions (2–4). ResultsRunning in a minimalist shoe at an increased cadence reduced patellofemoral stress and joint reaction force on average by approximately 29% (p<0.001) compared to the control condition. Running in a minimalist shoe at preferred cadence reduced patellofemoral joint stress by 15% and joint reaction force by 17% (p<0.001), compared to the control condition. Running in control shoes at an increased cadence reduced patellofemoral joint stress and joint reaction force by 16% and 19% (p<0.001), respectively, compared to the control condition. ConclusionsIn individuals with patellofemoral pain, running in a minimalist shoe at an increased cadence had the greatest reduction in patellofemoral joint loading compared to a control shoe at preferred cadence. This may be an effective intervention to modulate biomechanical factors related to patellofemoral pain.

Gait retraining versus foot orthoses for patellofemoral pain: a pilot randomised clinical trial

ObjectivesTo determine the feasibility of a clinical trial that compares a 6-week, physiotherapist-guided gait retraining program with a foot orthoses intervention in runners with patellofemoral pain. DesignPilot randomised controlled trial. MethodsRunners aged 18–40 years with clinically diagnosed patellofemoral pain were randomly allocated to either a 6-week gait retraining intervention of increasing cadence and use of a minimalist shoe or prefabricated foot orthoses. Outcomes at baseline and 12-weeks included recruitment, retention, adherence, adverse events, global improvement, anterior knee pain scale, worst and average pain on a 100mm visual analogue scale. ResultsOf the 16 randomised participants, two withdrew prior to commencing treatment due to non-trial related matters (n=1 from each group) and 14 completed the pilot trial. Minor calf muscle soreness was reported by 3 participants in the gait retraining group while no adverse events were reported in the foot orthoses group. There were no deviations from the treatment protocols. There was a large between-group difference favouring gait retraining at 12-weeks in the anterior knee pain scale and the worst pain in the past week, which was reflected in the number needed-to-treat of 2. ConclusionsThis study supports the feasibility of a trial comparing gait retraining with foot orthoses and provides point estimates of effect that informs the design and planning of a larger clinical trial. It appears that a 6-week gait retraining program has a clinically meaningful effect on runners with patellofemoral pain when compared to an evidence-based treatment of foot orthoses.

Shoe drop reduction influences the lower limb biomechanics of children tennis players during an open stance forehand: A longitudinal study

Compared to traditional tennis shoes, using 0-drop shoes was shown to induce an immediate switch from rear- to forefoot strike pattern to perform an open stance tennis forehand for 30% of children tennis players. The purpose of the study was to examine the long-term effects of a gradual reduction in the shoe drop on the biomechanics of children tennis players performing open stance forehands. Thirty children tennis players participated in 2 laboratory biomechanical test sessions (intermediate: +4 months and final: +8 months) after an inclusion visit where they were randomly assigned to control (CON) or experimental (EXP) group. CON received 12-mm-drop shoes twice, whereas EXP received 8 mm then 4-mm-drop shoes. Strike index indicated that all CON were rearfoot strikers in intermediate and final test sessions. All EXP were rearfoot strikers in intermediate test session, but half the group switched towards a forefoot strike pattern in final test session. This switch resulted in a decreased loading rate of the ground reaction force (−73%, p = .005) but increased peak ankle plantarflexors moment (+47%, p = .050) and peak ankle power absorption (+107%, p = .005) for these participants compared with CON. Biomechanical changes associated with the long-term use of partial minimalist shoes suggest a reduction in heel compressive forces but an increase in Achilles tendon tensile forces.

Effects of footwear and stride length on metatarsal strains and failure in running

BackgroundThe metatarsal bones of the foot are particularly susceptible to stress fracture owing to the high strains they experience during the stance phase of running. Shoe cushioning and stride length reduction represent two potential interventions to decrease metatarsal strain and thus stress fracture risk. MethodsFourteen male recreational runners ran overground at a 5-km pace while motion capture and plantar pressure data were collected during four experimental conditions: traditional shoe at preferred and 90% preferred stride length, and minimalist shoe at preferred and 90% preferred stride length. Combined musculoskeletal – finite element modeling based on motion analysis and computed tomography data were used to quantify metatarsal strains and the probability of failure was determined using stress-life predictions. FindingsNo significant interactions between footwear and stride length were observed. Running in minimalist shoes increased strains for all metatarsals by 28.7% (SD 6.4%; p<0.001) and probability of failure for metatarsals 2–4 by 17.3% (SD 14.3%; p≤0.005). Running at 90% preferred stride length decreased strains for metatarsal 4 by 4.2% (SD 2.0%; p≤0.007), and no differences in probability of failure were observed. InterpretationsSignificant increases in metatarsal strains and the probability of failure were observed for recreational runners acutely transitioning to minimalist shoes. Running with a 10% reduction in stride length did not appear to be a beneficial technique for reducing the risk of metatarsal stress fracture, however the increased number of loading cycles for a given distance was not detrimental either.

Habitual Minimalist Shod Running Biomechanics and the Acute Response to Running Barefoot.

The aim of the study was to determine whether habitual minimalist shoe runners present with purported favorable running biomechanithat reduce running injury risk such as initial loading rate. Eighteen minimalist and 16 traditionally cushioned shod runners were assessed when running both in their preferred training shoe and barefoot. Ankle and knee joint kinetics and kinematics, initial rate of loading, and footstrike angle were measured. Sagittal ankle and knee joint stiffness were also calculated. Results of a two-factor ANOVA presented no group difference in initial rate of loading when participants were running either shod or barefoot; however, initial loading rate increased for both groups when running barefoot (p=0.008). Differences in footstrike angle were observed between groups when running shod, but not when barefoot (minimalist:8.71±8.99 vs. traditional: 17.32±11.48 degrees, p=0.002). Lower ankle joint stiffness was found in both groups when running barefoot (p=0.025). These findings illustrate that risk factors for injury potentially differ between the two groups. Shoe construction differences do change mechanical demands, however, once habituated to the demands of a given shoe condition, certain acute favorable or unfavorable responses may be moderated. The purported benefits of minimalist running shoes in mimicking habitual barefoot running is questioned, and risk of injury may not be attenuated.

Acute kinematics changes in marathon runners using different footwear

ABSTRACTThe effects of running with or without shoes on injury prevention have been extensively studied, and several investigations have assessed biomechanical differences between them. However, findings are not consensual and further insights on biomechanical load associated with differently shod or barefoot conditions may be needed. This study aimed to observe if habitually shod marathon runners show acute alterations when running barefoot or with minimalist shoes, and to determine whether the running kinematical adaptations of wearing minimalist shoes were similar to barefoot running. Twelve male marathon runners ran on the treadmill at their average marathon pace in different footwear conditions: habitual running shoes, minimalist shoes, and barefoot. High-resolution infrared cameras and visual 3D software were used to assess kinematic data. The following parameters were studied: foot strike angle, cycle time, stance time, normalized stride length, hip, knee, and ankle angular position at initial contact, and their respective range-of-motion (ROM) during stance phase. Contrary to the expectations, it was found that highly trained habitually shod elite marathon runners changed their lower limb kinematic pattern both when running barefoot or wearing minimalist shoes. Minimalist shoes showed a trend towards intermediate biomechanical effects between running with and without shoes.

Walking in minimal shoes and standard hiking boots on smooth and rough surfaces

Walking in minimal shoes and standard hiking boots on smooth and rough surfaces

Do minimalist shoes improve balance and foot strength in older adults?

30% of people over 65 years old and 50% of people over 80 years old have at least one fall per year (NICE, 2013). One avenue explored to attempt to reduce this fall risk is footwear.Minimalist foot...

The Differential Effects of Footwear on Sample Entropy of Ground Reaction Force during Running

Maximum cushioned shoes could reduce the peak vertical Ground Reaction Force (GRF) during running, but it may increase the foot instability in horizontal directions, especially at the initial foot contact. Sample entropy (SampEn) has been adopted to define the irregularity to quantify levels of complexity of movement and examine the fluctuations in GRF within a time series. The foot instability would be better represented by the index of SampEn within a stance phase instead of variation among different stance phases viewing instability as errors. PURPOSE: this study was aimed at examining the complexity of GRF while running on the treadmill with different types of footwear through SampEn. METHODS: 19 experienced runners were recruited and ran on the treadmill at 7.8 mph wearing different types of running shoes: max cushioned shoe, minimalist shoe, and regular shoe. GRF of 10 consecutive steps were collected by the instrumented Tandem treadmill. GRF data were further analyzed to calculate sample entropy for both the first 20% stance phase and entire stance phase. Two-way MANOVA was used to examine the effects of independent variables (shoe, step) on sample entropy measures at first 20% stance phase (SampEn20%-ML, SampEn20%-AP, SampEn20%-VT) and entire stance phase (SampEnML, SampEnAP, SampEnVT). Post hoc Tukey test was applied as needed. RESULTS: a significant shoe effect was observed on the association among dependent variables listed above (P < .05). Cushioned shoes displayed a higher SampEnAP (.1162 ± .01558) than regular shoes (.1094 ± .0258) and a greater SampEn20%-AP (.1953 ± .1556) than minimalist shoes (.1546 ± .0932). Minimalist shoe exhibited greater SampEnVT (.0614 ± .01310) and SampEn20%-VT (.0636 ± .0688) than cushioned shoes (.0577 ± .1002; .0448 ± .0305) respectively. No other significant difference was observed. CONCLUSIONS: in general, cushioned shoes displayed more fluctuations of GRF in the anterior-posterior (AP) direction compared to minimalist and regular shoes, which indicates cushioned shoes may increase the foot instability in AP direction during running. Greater fluctuations of vertical GRF when wearing minimalist shoes may indicate a reduced foot stability that could affect the impact absorption at foot touchdown and force generation in push-off.

Manipulation of Foot Strike and Footwear Increases Achilles Tendon Loading During Running

Background: The Achilles tendon is the most common site of tendon overuse injury in humans. Running with a forefoot strike pattern and in minimal shoes is a topic of recent interest, yet evidence is currently limited regarding the combined influence of foot strike and footwear on Achilles tendon loading. Purpose: To investigate the influence of both foot strike and footwear on Achilles tendon loading in habitual rearfoot strike runners. Study Design: Controlled laboratory study. Methods: Synchronized kinematic and force data were collected from 22 habitual rearfoot strikers (11 male), who habitually ran in nonminimal running shoes, during overground running at 3.6 m·s-1. Participants ran in 3 different footwear conditions (standard running shoe, minimal running shoe, and barefoot) with both a rearfoot strike (RFS) and an imposed forefoot strike (FFS) in each footwear condition. Achilles tendon loading was estimated by use of inverse dynamics, where the Achilles tendon moment arm was determined with a regression equation. A 2-way, repeated-measures analysis of variance was used to compare conditions. Results: Achilles tendon impulse was greater when subjects ran with an FFS rather than an RFS in minimal shoes. Achilles tendon loading rates were higher when subjects ran either in minimal shoes or barefoot than in standard shoes, regardless of foot strike. Conclusion: In runners who habitually rearfoot strike in standard running shoes, running in minimal shoes or barefoot increased the rate of tendon loading, and running with a forefoot strike in minimal shoes increased the magnitude of tendon loading. Clinical Relevance: Transitioning to these running conditions may increase the risk of tendinopathy.

The Influence of Footwear on Running Mechanics, Impact, and Plantar Loading in Habitual Rearfoot Strikers

Running overuse injuries are related to the magnitude of impact forces and shocks, loading rates, and the distribution of forces underfoot. Minimalist shoes and barefoot running might reduce or eliminate running impacts by encouraging softer landings. However, reduced cushioning could increase plantar loading and some runners may not alter their habitual running mechanics to account for less cushioning. PURPOSE: To examine the acute effects of a cushioned neutral shoe (CN), minimal shoes (MN), and neoprene socks (BF) on running mechanics, impact, and plantar pressure. METHODS: Forty habitual rearfoot strikers ran on an instrumented treadmill while 3D kinematics, ground reactions forces (GRF), tibial accelerations (TA), and plantar pressure were recorded. Variables examined included: foot and knee angle at contact, vertical GRF loading rate (VLR), the isolated impact component of vertical GRF (IP), and the magnitude of peak positive to negative TA. Peak plantar pressure was compared for the forefoot (FFP), midfoot (MFP), and rearfoot (RFP). Differences were compared with a RMANOVA and post hoc t-tests (α=0.05). RESULTS: With less cushioning the foot was less dorsiflexed at contact BF 8.6±5.3° < MN 11.30±5.0 ° < CN 16.0±4.4° (p<0.01). The knee was more extended at contact in CN 13.3±6.6° than MN 14.8±5.9° and BF 15.2±5.8° (p<0.001). VLR was less in CN 670±212 N/kg/s compared to MN 980±268 N/kg/s and BF 975±371 N/kg/s (p<0.001) as was IP 4.1±16 N/kg vs 6.8±2.6 N/kg & 6.7±3.2 N/kg (p<0.001). TA was lower in CN 9.4±4.2 g than BF 12.6±6.7 g and MN 11.4±5.5 g (p<0.01). FFP increased with less cushioning: CN 330±70 kPa < MN 430±87 kPa < BF 561±76 kPa (p<0.001). MFP was less in CN 144±35 kPa compared to MN 212±58 kPa and BF 224±108 kPa (p<0.05). RFP was lower in CN 253±52 kPa vs MN 272±81 kPa and BF 396±170 kPa (p<0.001). CONCLUSION: Less cushioning resulted in a more compliant configuration of the limb at ground contact, which agrees with previous research. However, the CN shoe reduced VLR, IP, and TA compared to MN and BF despite a more extended knee and dorsiflexed foot. Lower peak plantar pressures in CN suggest that cushioning better distributes plantar forces of a less compliant limb particularly in the rearfoot. These results highlight the importance of both cushioning and mechanics on injury related variables.

Six-week transition to minimalist shoes improves running economy and time-trial performance.

This study investigated if gradually introducing runners to minimalist shoes during training improved running economy and time-trial performance compared to training in conventional shoes. Changes in stride rate, stride length, footfall pattern and ankle plantar-flexor strength were also investigated. Randomised parallel intervention trial. 61 trained runners gradually increased the amount of running performed in either minimalist (n=31) or conventional (n=30) shoes during a six-week standardised training program. 5-km time-trial performance, running economy, ankle plantar-flexor strength, footfall pattern, stride rate and length were assessed in the allocated shoes at baseline and after training. Footfall pattern was determined from the time differential between rearfoot and forefoot (TDR-F) pressure sensors. The minimalist shoe group improved time-trial performance (effect size (ES): 0.24; 95% confidence interval (CI): 0.01, 0.48; p=0.046) and running economy (ES 0.48; 95%CI: 0.22, 0.74; p<0.001) more than the conventional shoe group. There were no minimalist shoe training effects on ankle plantar-flexor concentric (ES: 0.11; 95%CI: -0.18, 0.41; p=0.45), isometric (ES: 0.23; 95%CI: -0.17, 0.64; p=0.25), or eccentric strength (ES: 0.24; 95%CI: -0.17, 0.65; p=0.24). Minimalist shoes caused large reductions in TDR-F (ES: 1.03; 95%CI: 0.65, 1.40; p<0.001) but only two runners changed to a forefoot footfall. Minimalist shoes had no effect on stride rate (ES: 0.04; 95%CI: -0.08, 0.16; p=0.53) or length (ES: 0.06; 95%CI: -0.06, 0.18; p=0.35). Gradually introducing minimalist shoes over a six-week training block is an effective method for improving running economy and performance in trained runners.

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.

Comparison of Running Economy Values While Wearing No Shoes, Minimal Shoes, and Normal Running Shoes.

Cochrum, RG, Connors, RT, Coons, JM, Fuller, DK, Morgan, DW, and Caputo, JL. Comparison of running economy values while wearing no shoes, minimal shoes, and normal running shoes. J Strength Cond Res 31(3): 595-601, 2017-The purpose of this study was to quantify differences in running economy (RE) at 50 and 70% of each subject's velocity at V[Combining Dot Above]O2max (vV[Combining Dot Above]O2max) across barefoot and 2 mass, stack height, and heel-to-toe-drop controlled footwear conditions (minimal shoes and normal running shoes) in 9 recreational distance runners (mean age 26.8 ± 6.8 years). Over 3 days, subjects ran in one of the footwear conditions while RE (oxygen consumption) and step frequency were measured at each speed with a 5-minute rest between each trial. A 2-way repeated-measures multivariate analysis of variance (p ≤ 0.05) and Bonferroni-adjusted follow-up analyses revealed that RE was not significantly different across footwear conditions at either speed. However, those running barefoot exhibited a higher step frequency than when running in minimal (50%, p = 0.007; and 70%, p < 0.001) and standard footwear conditions (70% only, p < 0.001). Higher step frequencies were also exhibited by those running in minimal versus standard footwear (70% only, p = 0.007). Thus, RE is not affected by footwear or running barefoot in those with experience running in minimal-type footwear. Significant adjustments in step frequency when alternative footwear was introduced may help explain why RE was statistically maintained during each footwear and speed condition across but not between subjects. Therefore, determination of footwear for the enhancement of RE should be based on individual physical characteristics and preferences rather than a global recommendation of an economical running shoe.

IS SHOE DROP A KEY FACTOR FOR INJURY PREVENTION IN RUNNING? PART 2: AN RCT ON RUNNING BIOMECHANICS

BackgroundSo far, only few biomechanical studies have specifically addressed the acute effect of the heel-to-toe drop in running shoes, but longitudinal studies are lacking.ObjectiveOur aim was to investigate if the...

The Effects of Minimal Shoe on Lower Extremity Biomechanics and Safety During Running

The Effects of Minimal Shoe on Lower Extremity Biomechanics and Safety During Running

Body Mass and Weekly Training Distance Influence the Pain and Injuries Experienced by Runners Using Minimalist Shoes: A Randomized Controlled Trial

Background: Minimalist shoes have been popularized as a safe alternative to conventional running shoes. However, a paucity of research is available investigating the longer-term safety of minimalist shoes. Purpose: To compare running-related pain and injury between minimalist and conventional shoes in trained runners and to investigate interactions between shoe type, body mass, and weekly training distance. Study Design: Randomized clinical trial; Level of evidence, 2. Methods: Sixty-one trained, habitual rearfoot footfall runners (mean ± SD: body mass, 74.6 ± 9.3 kg; weekly training distance, 25 ± 14 km) were randomly allocated to either minimalist or conventional shoes. Runners gradually increased the time spent running in their allocated shoes over 26 weeks. Running-related pain intensity was measured weekly by use of 100-mm visual analog scales. Time to first running-related injury was also assessed. Results: Interactions were found between shoe type and weekly training distance for weekly running-related pain; greater pain was experienced with minimalist shoes (P < .05), and clinically meaningful increases (>10 mm) were noted when the weekly training distance was more than 35 km/wk. Eleven of 30 runners sustained an injury in conventional shoes compared with 16 of 31 runners in minimalist shoes (hazard ratio, 1.64; 95% confidence interval, 0.63-4.27; P = .31). A shoe × body mass interaction was found for time to first running-related injury (P = .01). For runners using minimalist shoes, relative to runners using conventional shoes, the risk of sustaining an injury became more likely with increasing body mass above 71.4 kg, and the risk was moderately increased (hazard ratio, 2.00; 95% confidence interval, 1.10-3.66; P = .02) for runners using minimalist shoes who had a body mass of 85.7 kg. Conclusions: Runners should limit weekly training distance in minimalist shoes to avoid running-related pain. Heavier runners are at greater risk of injury when running in minimalist shoes. Registration: Australian New Zealand Clinical Trials Registry (ACTRN12613000642785).