The effects of minimalist footwear on stability, change of direction, and power production: a randomized crossover trial

The aim of the current study was to comparatively examine the effects of minimalist and conventional footwear on the loads experienced by the tibiofemoral joint during running. Ten male participants ran at 4.0 m/s (±5%) over a force platform in minimalist and conventional footwear. Kinematics of the lower extremities were collected using an eight camera motion capture system. Peak tibiofemoral force, peak tibiofemoral stress and tibiofemoral force experienced per mile were extracted and compared between footwear using paired t-tests. The results showed that no differences (P>0.05) in peak force (conventional = 40.02±6.45 and minimalist = 38.68±7.79 N/kg), peak stress (conventional = 14.54±1.77 and minimalist = 13.98±2.52 MPa) or force experienced per mile (conventional = 3,358.35±584.83 and minimalist = 3,308.04±636.31 N/kg·mile) were evident between footwear. Therefore this indicates that minimalist footwear may not provide any further protection from running related tibiofemoral pathologies compared to conventional footwear.

Little is known about the effects of different footwear on anaerobic performance variables. The purpose of this study was to investigate the effect of different footwear on vertical jumping and landing parameters. Ten men and 10 women participated. After a dynamic warm-up, subjects performed a vertical jump (VJ), depth drop (DD), and Bosco test on a force plate in 3 different conditions, on 3 separate days: bare feet (BF), minimalist footwear (MF), and tennis shoes (TS). Bare feet had greater relative peak power (relPP) in the VJ (men: BF, 59.87 ± 5.09 W⋅kg(-1); MF, 58.39 ± 5.69 W·kg(-1); TS, 57.70 ± 6.54 W·kg(-1); women: BF, 45.26 ± 4.10 W·kg(-1); MF, 45.06 ± 3.53 W·kg(-1); TS, 44.77 ± 4.55 W·kg(-1)), while for men, jump height (JH) was also greater in BF and MF (BF, 44.5 ± 4.46 cm; MF, 43.47 ± 5.5 cm; TS, 41.47 ± 14.45 cm). Results of the Bosco test revealed average relPP was greatest in BF compared with MF and TS (men: BF, 19.70 ± 3.01 W·kg(-1); MF, 19.28 ± 3.00 W·kg(-1); TS, 18.93 ± 3.33 W·kg(-1); women: BF, 14.68 ± 1.41 W·kg(-1); MF, 13.97 ± 1.56 W·kg(-1); TS 13.62 ± 1.67 W·kg(-1)), while for JH, BF and MF were greater than TS (men: BF, 28.62 ± 5.0 cm; MF, 27.78 ± 5.09 cm; TS, 26.54 ± 5.1 cm; women: BF, 18.60 ± 1.97 cm; MF, 17.86 ± 6.35 cm; TS, 17.35 ± 2.47 cm). No differences in relative impact force were seen during the DD between conditions. Therefore, athletes and coaches interested in enhancing single and multiple VJs might consider either BF or minimalist shoes.

The current study aimed to comparatively examine the effects of minimalist, maximalist, and conventional footwear on the loads experienced by the patellofemoral joint during running. Twenty male participants ran over a force platform at 4.0 m×s-1. Lower limb kinematics were collected using an 8-camera motion capture system allowing patellofemoral kinetics to be quantified using a musculoskeletal modeling approach. Differences in patellofemoral kinetic parameters were examined using one-way repeated-measures ANOVA. The results showed the peak patellofemoral force and pressure were significantly larger in conventional (4.70 ± 0.91 BW, 13.34 ± 2.43 MPa) and maximalist (4.74 ± 0.88 BW, 13.59 ± 2.63 MPa) compared with minimalist footwear (3.87 ± 1.00 BW, 11.59 ± 2.63 MPa). It was also revealed that patellofemoral force per mile was significantly larger in conventional (246.81 ± 53.21 BW) and maximalist (251.94 ± 59.17 BW) as compared with minimalist (227.77 ± 58.60 BW) footwear. As excessive loading of the patellofemoral joint has been associated with the etiology of patellofemoral pain symptoms, the current investigation indicates that minimalist footwear may be able reduce runners' susceptibility to patellofemoral disorders.

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

PurposeThe aim of the current investigation was to examine the effects of different footwear on the kinetics and kinematics of performing a 180° cutting manoeuvre.MethodsNine male participants performed maximal 180° cut movements in court shoes, minimalist footwear, energy return, and conventional running shoes. Lower limb kinematic data were collected with the use of an 8 camera motion capture system, ground reaction forces were quantified with an embedded force platform, and tibial accelerations were obtained by means of an accelerometer. Differences in kinetics and kinematics between footwear were examined by one-way repeated measures ANOVA.ResultsThe results showed that both instantaneous loading rate and peak tibial acceleration were significantly larger in the minimalist (282.91 BW/s and 6.38 g) and court (326.67 BW/s and 6.35 g) footwear compared with the conventional (143.19 BW/s and 5.46 g) and energy return (106.14 BW/s and 4.98 g) footwear. In addition, peak inversion was revealed to be significantly larger in the minimalist (16.36°) than in conventional (11.86°), court (12.61°), and energy return (10.12°) footwear.ConclusionsThese findings indicate that minimalist and court footwear may place athletes at increased risk from injury when performing 180° cut movements.

The current investigation aimed to comparatively examine the effects of minimalist, maximalist and conventional footwear on Achilles tendon forces (ATF) during running. Twelve male runners (age 23.11±5.01 years, height 1.78±0.10 cm and body mass 77.13±7.89 kg) ran at 4.0 m/s in the three footwear conditions. ATF’s were calculated using Opensim software allowing the magnitudal and temporal aspects of the ATF to be quantified. Differences between footwear were examined using one-way repeated measures ANOVA. The results showed the peak ATF was significantly larger in minimalist footwear (5.97±1.38 body weight (BW)) compared to maximalist (5.07±1.42 BW). In addition it was revealed that ATF per mile was significantly larger in minimalist (492.31±157.72 BW) in comparison to both maximalist (377.31±148.06 BW) and conventional (402.71±125.51 BW) footwear. Given the relationship between high ATF and Achilles tendon degradation, the current investigation indicated that minimalist footwear may increase runners risk for Achilles tendon injury.

The aim of the current investigation was to comparatively assess the influence of barefoot, CrossFit, minimalist and conventional footwear on the loads experienced by the Achilles tendon during running. Twelve male runners (27.81 ± 7.02 years, height 1.77 ± 0.11 cm and body mass 76.22 ± 7.04 kg) ran at 4.0 m·s-1 in each of the four footwear conditions. Achilles tendon forces were calculated using a musculoskeletal modelling approach allowing the magnitudinal and temporal aspects of the Achilles tendon force to be quantified. Differences between footwear were examined using one-way repeated measures ANOVA. The results showed the peak Achilles tendon force was significantly larger when running barefoot (5.81 ± 1.21) and in minimalist footwear (5.64 ± 1.03 BW) compared to conventional footwear (5.15 ± 1.05 BW). In addition it was revealed that Achilles tendon impulse was significantly larger when running barefoot (0.77 ± 0.22 BW.s) and in minimalist footwear (0.72 ± 0.16 BW.s) in comparison to both conventional footwear (0.64 ± 0.15 BW.s). Given the proposed association between high Achilles tendon forces and tendon degradation, the outcomes from the current investigation indicate that CrossFit athletes who select barefoot and minimalist footwear for their running training may be at increased risk from Achilles tendon pathology in comparison to conventional footwear conditions.

Comparing lower-limb asymmetries in NCAA D-I male and female athletes. This study is a hypothesis generating investigation of athletic asymmetries. Asymmetries can lead to poor sport performance, and injury. Evidence suggests that right and left side lower body asymmetries can lead to lower body pain and injury including increased back pain. Asymmetries appear to be dependent on factors such as neuromuscular, perceptual, kinesthetic requirements and the amount of experience in a specific event. It is possible that lower body symmetry can affect superior performance in many athletic tasks. PURPOSE: The purpose of this study was to investigate the strength characteristics and incidence of lower-limbs asymmetries in NCAA Division-I athletes. METHODS: Twenty-seven athletes (M = 19, F = 8) completed isometric mid-thigh pulls on a dual force plate as part of an on-going athlete monitoring program. Maximum strength was measured using an isometric pull from mid-thigh. Athletes performed isometric pulls (mid-thigh, knee angle 120° – 135°) in a custom designed force rack over a force plate (1000 Hz). Athletes' hands were attached to the bar using weightlifting straps and athletic tape and were explicitly instructed to perform the pull “as hard and fast as possible.” Pulls generally lasted 4 to 5 seconds and were terminated when peak force began to diminish. Two pulls were performed with two minutes rest between. Force values (IPF, force at 50, 90 and 250 ms) and rate of force development (RFD) values were obtained from the force-time curve. RFD was determined at 0-50ms, 0-90ms and 0-250ms. Previous work (several hundred trials) with this system has consistently resulted in test-retest reliability for IPF of ICCα ≥ 0.99 and RFD, ICCα ≥ 0.9. Statistical analysis using adjusted paired two-tailed t-Tests (p ≤ 0.016) were used to compare male and female asymmetries. RESULTS: Males exhibited no statistical difference in peak force (6%), force at different intervals 50 (6%), 90, (8%) and 250 ms (6%), or rate of force development at different intervals when comparing dominant versus non-dominant leg. However, when comparing dominant versus non-dominant leg in females, there was a significant difference in peak force (13%), and force at 50 (8%), 90 (8%), and 250 ms (10%). When comparing all subjects for left and right asymmetries, there was a significant difference in left versus right peak force (6%), force at all measured time intervals (50 (9%), 90 (8%), 250 ms (7%)), and RFD at 0-50 ms (18%). Males had no significant difference in left versus right leg RFD (19%); however there was a significant difference in peak force (11%), and force at 50 (9%) and 250 ms (7%). Females had a significant difference between right and left leg peak force at 50 (8%) and 90ms (7%), and rate of force development at 50ms (21%). CONCLUSIONS: The results show that as a collective group, the subjects had a degree of asymmetry in force measurements. When separated for sex, males had significant differences in right versus left force characteristics, but not dominant versus non-dominant, whereas females had significant differences in both left versus right and dominant versus non-dominant. PRACTICAL APPLICATION: Differences in right/left and dominate/non-dominant lower body strength characteristics could indicate potential concerns dealing with both performance and injury. This data also indicates that female athletes may be more vulnerable to performance aberrations and injury compared to males.

The aim of this work was to examine the effects of barefoot, cross-fit, minimalist and conventional footwear on patellofemoral loading during running. Twelve cross-fit athletes ran at 4.0 m/s in each of the four footwear conditions. Lower limb kinematics were collected using an 8 camera motion analysis system and patellofemoral loading was estimated using a mathematical modelling approach. Differences between footwear were examined using one-way repeated measures ANOVA. The results showed the peak patellofemoral force and stress were significantly reduced when running barefoot (force = 3.42 BW & stress = 10.71 MPa) and in minimalist footwear (force = 3.73 BW & stress = 11.64 MPa) compared to conventional (force = 4.12 BW & stress = 12.69 MPa) and cross-fit (force = 3.97 BW & stress = 12.30 MPa) footwear. In addition, the findings also showed that patellofemoral impulse was significantly reduced when running barefoot (0.35 BW·s) and in minimalist footwear (0.36 BW·s) compared to conventional (0.42 BW·s) and cross-fit (0.38 BW·s) footwear. Given the proposed association between patellofemoral loading and patellofemoral disorders, the outcomes from the current investigation suggest that cross-fit athletes who select barefoot and minimalist footwear for their running activities may be at reduced risk from patellofemoral joint pathology in comparison to conventional and cross-fit footwear conditions.

Chronic effects of a flexible and minimalist footwear on clinical, functional and gait biomechanical aspects in the knee osteoarthritis: a single-blind randomized clinical trial

The aim of the current study was to comparatively examine the effects of barefoot, cross-fit, minimalist and conventional footwear on the kinetics and kinematics of running. Thirteen male participants ran over an embedded force platform at 4.0 m/s in the four different footwear conditions. Lower extremity kinematics were quantified via an eight-camera motion analysis system and tibial accelerations were obtained using a distally mounted accelerometer. Differences between footwear were investigated using one-way, repeated measures ANOVA. The findings confirmed that instantaneous loading rate and peak tibial acceleration were significantly larger in the barefoot (274.19 BW/s and 5.72 g) and minimalist (302.91 BW/s and 5.31 g) conditions in relation to the conventional (112.37 BW/s and 4.55 g) footwear. In addition it was also shown that ankle angle at footstrike was significantly more plantarflexed in the barefoot (−8.70°) and minimalist (−.92°) conditions compared to the conventional (5.09°) and cross-fit (2.16°) conditions. As such the results from the current investigation indicate that barefoot and minimalist footwear may place cross-fit athletes at increased risk from chronic pathologies during running activities.

The effect of footwear and footfall pattern on running stride interval long-range correlations and distributional variability

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

Changes in typical strain magnitude or distribution with fatigue are theorized to increase the risk of stress fractures in runners. However there are few data that assess changes in biomechanics with fatigue in runners prone to stress fractures. PURPOSE: To characterize within and between group differences in mean peak force (PF) and center of foot pressure (COFP) during a fatigue run in female runners with (SFX) and without (CON) a history of tibial stress fracture. METHODS: Fatigue runs were performed by 6 SFX (24.4 ± 4.2y) and 16 CON (23.6 ± 5.8y) at anaerobic threshold pace. Pressure measuring shoe insoles were used to measure PF and COFP for 30s of each minute until a perceived exertion of 20 was reached. Changes in PF and COFP (x and y) were calculated relative to the first trial. COFP-x was used as an indicator of medial-lateral stability and measured in two anatomical regions of the foot (mid- and fore-foot). Repeated measures ANOVA was used to determine between and within group change over 7 intervals of the fatigue run (5, 25, 50, 75, 85, 90, 95%). RESULTS: COFP-y remained stable over time within the control group for both the left and right side. In contrast, SFX had significant decrease in the left foot COFP-y relative to baseline at the 25, 50, 75, and 90% intervals (p < 0.05). Fore-foot mediallateral variability (COFP-x) increased over time in SFX at all intervals in both the left and right side and in CON at all intervals with the exception of the 75 which approached significance (p = 0.052). Similarly, mid-foot COFP-x changed over time in both groups with significant differences during the 25 to 95% on the left foot and at nearly all time points on the right foot. Interestingly, within group differences in peak force were only present in CON left foot at the 50, 75 and 90%. Due to the variability in outcomes, there were no between group differences for any variable. CONCLUSIONS: Overall, these data suggest that biomechanical adaptation to fatigue occur primarily by increasing medial-lateral variability with few consistent changes in peak force. There were no consistent differences in adaptation to fatigue between runners with and without a history of stress fracture.

BackgroundFootwear has been shown to influence balance and is an important consideration in relation to the prevention of falls. However, it remains unclear as to what type of footwear is most beneficial for balance in older people: sturdy, supportive footwear, or minimalist footwear to maximise plantar sensory input. The objectives of this study were therefore to compare standing balance and walking stability in older women wearing these two footwear styles, and to investigate participants’ perceptions in relation to comfort, ease of use and fit.MethodsOlder women (n = 20) aged 66 to 82 years (mean 73.4, SD 3.9) performed a series of laboratory tests of standing balance (eyes open and closed on floor and foam rubber mat, near tandem standing) and walking stability (treadmill, level and irregular surface) using a wearable sensor motion analysis system. Participants were tested wearing supportive footwear (incorporating design features to improve balance) and minimalist footwear. Perceptions of the footwear were documented using structured questionnaires.ResultsThere were no statistically significant differences in balance performance between the supportive and minimalist footwear. Participants perceived the supportive footwear to be significantly more attractive to self and others, easier to put on and off but heavier compared to the minimalist footwear. Overall comfort was similar between the footwear conditions, although the supportive footwear was reported to be significantly more comfortable in the heel, arch height, heel cup, heel width and forefoot width regions. Eighteen participants (90%) reported that they felt more stable in the supportive footwear and 17 (85%) reported that they would consider wearing them to reduce their risk of falling.ConclusionBalance performance and walking stability were similar in supportive footwear designed to reduce the risk of falling and minimalist footwear, although participants preferred the supportive footwear in relation to aesthetics, ease of use, comfort and perceived stability. Prospective studies are now required to ascertain the longer-term advantages and disadvantages of these footwear styles on comfort and stability in older people.Trial registrationAustralian New Zealand Clinical Trials Registry. ACTRN12622001257752p, 20/9/2022 (prospectively registered).