Journal Information
Vol. 53. Num. 199.July - September 2018
Pages 87-124
Share
Share
Download PDF
More article options
Visits
310
Vol. 53. Num. 199.July - September 2018
Pages 87-124
Original Article
DOI: 10.1016/j.apunts.2017.11.004
Full text access
Can running kinetics be modified using a barefoot training program?
¿Puede modificarse la cinética de la carrera mediante un programa de entrenamiento descalcista?
Visits
310
Marcos Muñoz Jiméneza,
Corresponding author
mmj00006@red.ujaen.es

Corresponding author.
, Felipe García-Pinillosb, Víctor M. Soto-Hermosoc, Pedro A. Latorre-Romána
a University of Jaen, Department of Didactics of Corporal Expression, Campus de Las Lagunillas s/n, D2 Building, Dep. 142.23071 Jaén, Spain
b Universidad de La Frontera, Department of Physical Education, Sports and Recreation, Temuco, Chile
c University of Granada, Department of Sports Sciences, Carretera de Alfacar s/n, 18071 Granada, Spain
This item has received
310
Visits
Article information
Abstract
Full Text
Bibliography
Download PDF
Statistics
Figures (1)
Tables (2)
Table 1. Weekly training protocol used during the study.
Table 2. Temporal variables results.
Show moreShow less
Abstract
Introduction

There is limited information about barefoot transition programs and this study will help to increase knowledge about this growing trend. The purpose of this study was, therefore, to determine the effect of a twelve-week barefoot training program on kinematic variables in long-distance runners.

Materials and methods

A total of 32 well-trained, habitually shod, long-distance runners, randomized in a control group and an experimental group who undertook a barefoot training program. At pre-test and post-test, all participants, wearing their usual sneakers, performed running tests at self-selected recovery and competitive running speeds on a treadmill. Both conditions were recorded with a 240Hz video rate system and analyzed using a 2-D video editing program using photogrammetric techniques. Contact time, flight time, step duration and cadence were measured using an analysis of variance (ANOVA) with repeated measures was performed.

Results

In posttest, only the duration of landing phase at high speed showed significant difference, the experimental group achieved a shorter time than the control group after the barefoot training program (0.032±0.007s vs. 0.038±0.006s). In relation to within-group differences, the control group showed an increase of duration of stance phase at low speed (Δ=0.014s, p=0.024) and a reduction of flight time at high speed (Δ=−0.014s, p=0.034). Moreover, the experimental group achieved a reduction of duration of landing phase at high speed (Δ=−0.008s, p=0.004).

Conclusions

A twelve-week program of barefoot running changes the duration of the landing phase at high speed, being shorter in long-distance runners. In contrast, the runners who did not undertake the training showed an increase of duration of stance phase at low speed.

Keywords:
Athletic performance
Joints
Running
Resistance
Unshod
Resumen
Introducción

Existe información limitada acerca de los programas de transición a carrera descalza, y este estudio ayudará a incrementar el conocimiento acerca de esta tendencia creciente. Por tanto, el objetivo de este estudio fue determinar el efecto de un programa de entrenamiento descalcista de 12 semanas sobre las variables cinéticas en los corredores de larga distancia.

Materiales y métodos

Un total de 32 corredores de larga distancia, bien entrenados, y habitualmente calzados, fueron distribuidos aleatoriamente en un grupo experimental para llevar a cabo un programa de entrenamiento descalcista. Durante las pruebas previas y posteriores, todos los participantes realizaron las pruebas a velocidades de carrera de recuperación y competitiva auto-seleccionadas, utilizando sus zapatillas deportivas en una cinta ergométrica. Ambas situaciones se registraron con un sistema de calificación por vídeo de 240Hz, y se analizaron mediante un programa de edición de vídeo 2D con técnicas fotogramétricas. Se midieron el tiempo de contacto, la duración del paso y la cadencia mediante análisis de la varianza (ANOVA) con mediciones repetidas.

Resultados

En la prueba posterior, solo la duración de la fase de aterrizaje a alta velocidad reflejó una diferencia significativa, logrando el grupo experimental un tiempo inferior que el grupo control tras el programa de entrenamiento descalcista (0,032±0,007s frente a 0,038±0,006s). Con relación a las diferencias entre grupos, el grupo control reflejó un incremento en la duración de la fase de apoyo a baja velocidad (Δ=0,014s; p=0,024) y una reducción del tiempo de vuelo a alta velocidad (Δ=−0,014s; p=0,034). Además, el grupo experimental logró una reducción de la duración de la fase de aterrizaje a alta velocidad (Δ=−0,008s; p=0,004).

Conclusiones

Un programa de carrera descalcista de 12 semanas modifica la duración de la fase de aterrizaje a alta velocidad, que es más corta en los corredores de larga distancia. Por contra, los corredores que no realizaron el entrenamiento reflejaron un incremento de la duración de la fase de apoyo a baja velocidad.

Palabras clave:
Desempeño atlético
Articulaciones
Carrera
Resistencia
Descalzo
Full Text
Introduction

Some authors suggest that habitual barefoot running could prevent impact-related injuries.1–3 Some studies pointed that humans had been made to run barefoot, and this running style can minimize impact peaks and provides increased proprioception and foot strength, also is hypothesized that can help avoid injury.4 In order to reduce the risk of injury, the runner's body produces changes in lower limb kinematics. Some authors have measured the risk of injury in runners’ feet before and after a training period transitioning from traditional to minimalist running shoes, participants in the training group showed significant increases in bone marrow edema in at least one bone after the training running period.5,6 Furthermore, barefoot running is also associated with a shorter stride a higher stride cadence both low and high running speed,7,8 reducing stride length decreased the probability of stress fracture by 3–6%.5

Previous studies of barefoot running specify even more the kinematic changes such as: shorter step length and larger step frequency, shorter landing phase, shorter contact time, shorter flight time and shorter step time.7–11 Barefoot running is also related with a higher stride cadence both low and high running speed.7,8 In addition, barefoot running reduces flight time and causes a lower peak force and higher pre-activation of the sural triceps than shod running.12

A recent study pointed that an intervention of six weeks of barefoot training simulation using Vibram Five-fingers shoes, is associated with a significant decrease in the loading rates and impact forces.13 Other study question about the process in which biomechanical adaptations happen and if these can be learned by everyone.14 It remains to be seen how training based on barefoot running can modify the kinematics of traditionally shod running. There are many aspects concerning the manner in which the athletes adapt kinematics variables to run after specific barefoot training but there is already no evidence for long term effects of barefoot running regarding biomechanics or health outcomes.15 This insight could be enhanced by studying the difference in kinematics after a sufficiently long controlled barefoot training program (BTP).

Considering the above information, we hypothesized that neuromuscular adaptations to BTP might be responsible for the change in kinematic variables in shod condition post-intervention. Therefore, the purpose of this study is to determine if after the 12-week barefoot intervention the pointed variables will be modified even when running shoes are put on.

Materials and methods

This experimental study was conducted in adherence to the standards of the Declaration of Helsinki (2013 version) and followed the European Community's guidelines for Good Clinical Practice (111/3976/88 of July 1990), as well as the Spanish legal framework for clinical research on humans (Royal Decree 561/1993 on clinical trials). The informed consent and the study were approved by the Bioethics Committee of the University of Jaen (Spain).

Participants

Thirty-nine trained shod runners from southeast of Spain participated voluntarily in this study and were randomly allocated by simple random sampling in the experimental group (EG), and control group (CG). The main characteristics of the participants were age=35.64±11.67-years-old (mean±standard deviation); body mass index=22.93±2.43kg/m2; km per week=60.18±20.41; sessions per week=5.47±1.29; and competitions per year=13.08±10.50. Only two athletes in the EG left the program because of illness. In the CG six people did not finish, because of illness during the intervention (n=1) or did not perform the post-test (n=3) or the data were corrupt or illegible (n=2). All the data from lost athletes were excluded (Fig. 1).

Figure 1.
(0.35MB).

Flowchart progress through the study participants.

The inclusion criteria were: (i) participants were all habitually shod runners (cushioned shoes); (ii) no significant injuries in the last three months and no damage or pain that could interfere with the proper monitoring of the training protocol without shoes; (iii) verifiable minimum sport level (have been able to participate in regional or national athletics championships in the last four years). Each participant signed an informed consent to participate in this research.

Measures

Participants were asked not to perform heavy physical exertion 72h before taking pre-test and post-test data.16 Participants were asked to run consistently at their comfortable recovery speed and their running 1500 meters long competition speed chosen by themselves17 to simulate as faithfully as possible their habitual recovery and competitive running pace and then proceeded to run on a mechanical treadmill (Salter E-Line PT-320, Salter International, Barcelona, Spain). When participants self-selected speeds for running, appeared to require fewer attempts before completing the acceptable trials needed for data collection as compared to when the subjects were running at the standardized speed selected by the investigators.17 Both running speeds were performed with their usual training shoes. Recordings of athletes were performed from sagittal and back view with a rate of 240Hz camcorders (Casio Exilim EX-F1, Shibuya-ku, Tokyo 151-8543, Japan). Cameras were placed two meters away from the treadmill at ground level. Marks were placed on the floor to indicate the exact point of the cameras. Video data were observed using a 2D video editing program (VideoSpeed vs.1.38, ErgoSport, Granada, Spain). Before recordings, the athletes warmed up and habituate to the treadmill and speed in each condition for about 8min. A period of 8min was chosen because previous studies on human locomotion have shown that accommodation to a new condition occurs within this period.18,19 Participants were instructed to run continuously during each trial without stops. Participants were freely allowed to adjust the speed up and down until they found a speed that matched their perceived over ground speed, which has been shown to improve the repeatability in kinematic variables.17 Speed was increased from recovery speed to competition speed. Eight steps of each athlete at high speed and low speed conditions were measured.

Based on previous studies variables tested were: total contact time (time the foot is in contact with the ground) divided into three different moments (landing phase, stance phase and take-off phase); flight time (time where there is no contact with the ground); step duration (total time of the movement of the lower limbs including flight phase and contact phase) and cadence (number of step per minute).7,10,20

Procedures

Following Lieberman4 the BTP consisted of the progressive inclusion in the usual weekly training of the EG of an increasing amount of barefoot running on a grass surface (Table 1). During the final weeks, more intense exercises such as progressive races were added. The principal researcher reviewed the implementation of the BTP and controlling the risk of significant aches and pains. Before starting the protocol, a meeting with the athletes in the EG was held to advise on training and any questions were explained and answered. The CG performed only the normal daily training. Athletes were informed of the possible increased risk of injury because of the possible changes in the pattern of the race and the strike. It was advised to decrease the intensity of training or even to abandon it when there was pain or injury. During the BTP, participants were not allowed to change their running shoes.

Table 1.

Weekly training protocol used during the study.

Weeks  Experimental group weekly workout 
1–2  Normal daily training.
+10′ barefoot running in 50% of the weekly sessions during cool down. 
3–4  Normal daily training.
+10′ barefoot running in 75% of the weekly sessions during cool down. 
5–6  Normal daily training.
+15′ in 75% of the weekly sessions during cool down. 
7–8  Normal daily training.
+20′ in 50% of weekly sessions during cool down.
+4 progressive 80-m races at 90–95% effort sprint. 
9–10  Normal daily training.
+20′ in 75% of weekly sessions during cool down.
+4 progressive 80-m races at 90–95% effort sprint. 
11–12  Normal daily training.
+40′ barefoot race once a week at recovery pace. +20′ in other two weekly sessions during cool down. 
Statistical analysis

The data were analyzed with the statistical program SPSS.v.19.0 for Windows, (SPSS Inc., Chicago, USA) and the significance level was set at P<0.05. The data are shown in descriptive statistics for mean and standard deviation (SD). Tests of normal distribution and homogeneity (Kolmogorov–Smirnov and Levene's, respectively) were conducted on all data before analysis. Analysis of variance (ANOVA) with repeated measures was performed between pre-test and post-test in EG and CG, taking as dependent variable, the experimental condition and the kinematic parameters as independent variables. A Student's t-test was performed to ascertain running speed differences.

Results

There are no significant differences between groups in relation to comfortable speed (EG=11.21±1.28km/h vs. CG=10.97±1.20km/h, p=0.611) and competition speed (EG=15.56±2.08km/h vs. CG=15.45±1.67km/h, p=0.873).

The results of BTP are presented in Table 2. At pre-test, no significant between-group differences were found in any variable. At post-test, only the duration of landing phase at high speed showed significant difference, the EG achieved shorter time than CG after the BTP (0.032±0.007s vs. 0.038±0.006s). In relation to within-group differences, CG showed an increase of stance phase at low speed (Δ=0.014s, p=0.024) and a reduction of flight time at high speed (Δ=−0.014s, p=0.034). Moreover, EG achieved a reduction of landing phase at high speed (Δ=−0.008s, p=0.004). No other significant differences were showed after BTP.

Table 2.

Temporal variables results.

  Pre-test
Mean (SD) 
Post-test
Mean (SD) 
Difference post–pre  p-Value  95% confidence interval 
Landing phase time at low speed (s)
CG  0.046 (0.010)  0.040 (0.010)  −0.006  0.069  −0.013/0.001 
EG  0.044 (0.014)  0.039 (0.011)  −0.005  0.065  −0.011/0.000 
Stance phase time at low speed (s)
CG  0.094 (0.022)  0.108 (0.010)  0.014  0.024  0.002/0.026 
EG  0.098 (0.017)  0.104 (0.014)  0.007  0.212  −0.004/0.017 
Take off phase time at low speed (s)
CG  0.129 (0.014)  0.131 (0.016)  0.002  0.772  −0.010/0.013 
EG  0.130 (0.015)  0.129 (0.018)  −0.001  0.833  −0.011/0.009 
Flight time at low speed (s)
CG  0.085 (0.025)  0.072 (0.032)  −0.013  0.111  −0.029/0.003 
EG  0.084 (0.027)  0.080 (0.028)  −0.004  0.548  −0.018/0.010 
Step duration at low speed (s)
CG  0.709 (0.046)  0.716 (0.039)  0.007  0.385  −0.010/0.025 
EG  0.706 (0.034)  0.699 (0.037)  −0.007  0.373  −0.022/0.009 
Landing phase time at high speed (s)
CG  0.038 (0.007)  0.038 (0.006)  0.000  0.916  −0.006/0.005 
EG  0.040 (0.009)  0.032 (0.007)*  −0.008  0.004  −0.012/−0.002 
Stance phase time at high speed (s)
CG  0.080 (0.013)  0.084 (0.019)  0.004  0.389  −0.006/0.015 
EG  0.080 (0.013)  0.080 (0.016)  0.000  0.923  −0.010/0.009 
Take off phase time at high (s)
CG  0.108 (0.010)  0.111(0.011)  0.003  0.547  −0.007/0.012 
EG  0.109 (0.013)  0.014 (0.017)  0.005  0.231  −0.003/0.013 
Flight time high at speed (s)
CG  0.103 (0.026)  0.089 (0.029)  −0.014  0.034  −0.028/−0.001 
EG  0.106 (0.022)  0.098 (0.028)  −0.008  0.194  −0.019/0.004 
Step duration at high speed (s)
CG  0.681 (0.042)  0.663 (0.048)  −0.018  0.140  −0.042/0.006 
EG  0.670 (0.033)  0.662 (0.045)  −0.008  0.478  −0.029/0.014 
Contact time at low speed (s)
CG  0.271 (0.035)  0.262(0.025)  −0.009  0.332  −0.027/0.009 
EG  0.270(0.025)  0.264 (0.029)  −0.006  0.477  −0.022/0.010 
Contact time at high speed (s)
CG  0.215 (0.023)  0.218 (0.029)  0.003  0.625  −0.011/0.017 
EG  0.214 (0.020)  0.220 (0.034)  0.006  0.348  −0.007/0.018 
Cadence step/min at low speed
CG  85.047 (5.942)  84.051(4.949)  −0.996  0.338  −3.084/1.092 
EG  85.178 (4.215)  86.043 (4.576)  0.865  0.345  −0.977/2.706 
Cadence step/min at high speed
CG  88.369 (5.707)  90.863 (6.530)  2.494  0.124  −0.723/5.711 
EG  89.709 (4.419)  90.902 (6.008)  1.193  0.397  −1.644/4.031 
*

Significant differences (p0.05) between EG and CG. EG: experimental group. CG: control group. SD: standard deviation.

Discussion

The purpose of this study was to determine the effects of a 12-week BTP on kinematic variables in long-distance runners. The main finding of this study showed that 12-week BTP does not alter significantly kinematic variables in long-distance runners. Only EG achieved a reduction of landing phase at high speed; no other significant differences were showed after BTP. Other studies found no changes in strength and proprioception after 8 weeks of a progressive BTP on a grass surface21 or changes in biomechanics after an 8-week, progressively introduced barefoot running program.22 Likewise, other studies showed that no biomechanical changes were found in the intervention group after 8 weeks of a progressive BTP.14 However, there was indicated that a 12-week intervention of controlled simulated barefoot running training was sufficient to elicit significant changes in lower limb kinematics not only during barefoot running, but also during running in regular cushioned running shoes.23 These controversial results indicate that future studies should be performed to clarify doubts about the effect of BTP on kinematic variables.

The authors suggest that the lack of significant effects in the current study may be due to several points: (i) shoes annul this effect; (ii) the insufficient duration of BTP; (iii) the insufficient load of the training program; (iv) the effect of training surface. When athletes run unshod, the hardness of the surface where they are running causes an alteration on foot strike pattern. In previous studies only the 20% of the participants ran with a midfoot or forefoot pattern on the soft surface whereas 65% of the participants ran with a midfoot or forefoot patterns on hard surface.24 Surface used in this study was grass, which may be a significant factor in causing no alteration in runner's kinematics pattern.

An unexplored area of the theory of barefoot running is the process by which biomechanical adaptations occur and if these are universally learned.14 Thus, the associated kinematic barefoot running can be a trainable ability, and requires adaptive training with changes in the neuromuscular activation of calf muscles to facilitate plantar flexion before ground impact. In this sense, when sufficient unshod steps in relation to shod steps, are made, this produces higher triceps sural muscles previous activation, which can lead to a reduction in the peak of impact and the subsequent reduction in mechanical stress during running.12,13

In contrast to recent studies in which numerous problems related to greater incidence of bone marrow edema due to barefoot training protocols and uncontrolled loads, a positive finding of this study may be the non-detection of physical problems or injuries occurring in athletes associated with designed barefoot training program.6 On balance a sufficient workload to cause changes in lower limb kinematics and a training protocol design which does not cause harm is needed. Referring to the correct progression from shod to barefoot condition, a prior step for adaptation to barefoot running could be minimalist footwear.

Finally, some limitations need to be considered such as 2D techniques in the video analysis. Moreover, it is very difficult to know how much barefoot training and at what intensity each subject has performed. It would be necessary to standardize training with caution to control the progress and problems of each athlete, as each runner progresses differently. Additionally, force measures does not has been included that would also be interesting to evaluate given their relationship to injury risk. However, the strengths of our study are that it provides new information about protocols for transitioning from shod to barefoot running and provides new insight into the already open debate about barefoot running with a protocol only based on running unshod without other interventions like plyometrics or neuromuscular workout. To the best of our knowledge, there is limited information about barefoot transition programs and this study will help to increase knowledge about this growing trend.

Conclusion

Despite no athlete suffered any harm during the study intervention, 12-week BTP based on the addition of barefoot running time at the end of daily training was not sufficient to cause chronic changes in lower limb kinematics shod, only in landing phase at high speed (that was lower). The authors suggest that running shoes may reduce the chronic effects of barefoot running. On the other hand, increasing the volume of workload or running on harder surfaces may be required to produce more chronic changes.

Conflict of interest

Authors declare that they don’t have any conflict of interests.

References
[1]
D.E. Lieberman,M. Venkadesan,W.A. Werbel,A.I. Daoud,S. D’Andrea,I.S. Davis
Foot strike patterns and collision forces in habitually barefoot versus shod runners
Nature, 463 (2009), pp. 531-535 http://dx.doi.org/10.1038/nature08723
[2]
B. Nigg,H. Enders
Barefoot running – some critical considerations
Footwear Sci, 5 (2013), pp. 1-7
[3]
A. Stacoff,B.M. Nigg,C. Reinschmidt,A.J. Van Den Bogert,A. Lundberg
Tibiocalcaneal kinematics of barefoot versus shod running
J Biomech, 33 (2000), pp. 1387-1395
[4]
D.E. Lieberman
What we can learn about running from barefoot running
Exerc Sport Sci Rev, 40 (2012), pp. 63-72 http://dx.doi.org/10.1097/JES.0b013e31824ab210
[5]
W. Brent Edwards,D. Taylor,T.J. Rudolphi,J.C. Gillette,T.R. Derrick
Effects of running speed on a probabilistic stress fracture model
Clin Biomech, 25 (2010), pp. 372-377
[6]
S.T. Ridge,A.W. Johnson,U.H. Mitchell,I. Hunter,E. Robinson,B.S.B.S. Rich
Foot bone marrow edema after 10-week transition to minimalist running shoes
Med Sci Sport Exerc, 45 (2013), pp. 1363-1368
[7]
B. De Wit,D. De Clercq,P. Aerts
Biomechanical analysis of the stance phase during barefoot and shod running
J Biomech, 33 (2000), pp. 269-278
[8]
M. Muñoz,F. García,V.M. Soto,P. Latorre-Román
Effects of barefoot running and running requirement on lower-limb kinematics in habitually shod endurance runners
Apunt Med l’Esport, (2016),
[9]
C. Divert,G. Mornieux,P. Freychat,L. Baly,F. Mayer,A. Belli
Barefoot-shod running differences: shoe or mass effect?
Int J Sports Med, 29 (2008), pp. 512-518 http://dx.doi.org/10.1055/s-2007-989233
[10]
R. Squadrone,C. Gallozzi
Biomechanical and physiological comparison of barefoot and two shod conditions in experienced barefoot runners
J Sports Med Phys Fitness, 49 (2009), pp. 6-13
[11]
M. Thompson,A. Gutmann,J. Seegmiller
The effect of stride length on the dynamics of barefoot and shod running
[12]
C. Divert,G. Mornieux,H. Baur,F. Mayer,A. Belli
Mechanical comparison of barefoot and shod running
Int J Sports Med, 26 (2005), pp. 593-598 http://dx.doi.org/10.1055/s-2004-821327
[13]
I.A. Khowailed,J. Petrofsky,E. Lohman,N. Daher
Six weeks habituation of simulated barefoot running induces neuromuscular adaptations and changes in foot strike patterns in female runners
Med Sci Monit, 21 (2015), pp. 2021-2030 http://dx.doi.org/10.12659/MSM.893518
[14]
N. Tam,J. Wilson,T. Noakes
Barefoot running: an evaluation of current hypothesis, future research and clinical applications
Brit J Sports Med, 48 (2014), pp. 349-355
[15]
K. Hollander,C. Heidt,B. van der Zwaard,K.M. Braumann,A. Zech
Long-term effects of habitual barefoot running and walking: a systematic review
Med Sci Sports Exerc, 49 (2017), pp. 752-762 http://dx.doi.org/10.1249/MSS.0000000000001141
[16]
F. García-Pinillos,V.M. Soto-Hermoso,P.A. Latorre-Román
Acute effects of extended interval training on countermovement jump and handgrip strength performance in endurance athletes: postactivation potentiation
J Strength Cond Res, 29 (2015), pp. 11-21 http://dx.doi.org/10.1519/JSC.0000000000000591
[17]
R.M. Queen,M.T. Gross,H.Y. Liu
Repeatability of lower extremity kinetics and kinematics for standardized and self-selected running speeds
Gait Posture, 23 (2006), pp. 282-287 http://dx.doi.org/10.1016/j.gaitpost.2005.03.007
[18]
V. Lavcanska,N.F. Taylor,A. Schache
Familiarization to treadmill running in young unimpaired adults
Hum Mov Sci, 24 (2005), pp. 544-557 http://dx.doi.org/10.1016/j.humov.2005.08.001
[19]
D.A. Schieb
Kinematic accommodation of novice treadmill runners
Res Quart Exerc Sport, 57 (1986), pp. 1-7
[20]
P.Á. Latorre-Román,F. García Pinillos,P. Bujalance-Moreno,V.M. Soto-Hermoso
Acute effects of high-intensity intermittent training on kinematics and foot strike patterns in endurance runners
J Sports Sci, 0 (2016), pp. 1-8
[21]
S. Mullen,J. Cotton,M. Bechtold,E.B. Toby
Barefoot running: the effects of an 8-week barefoot training program
Orthop J Sport Med, 2 (2014),
2325967114525582
[22]
R. Tucker,J. Wilson
Individual Responses to a Barefoot running program insight into risk of injury
Am J Sport Med, 44 (2016), pp. 777-784
[23]
C. McCarthy,N. Fleming,B. Donne
12 weeks of simulated barefoot running changes foot-strike patterns in female runners
Int J Sport Med, 35 (2014), pp. 443-450
[24]
A.H. Gruber,J.F. Silvernail,P. Brueggemann,E. Rohr,J. Hamill
Footfall patterns during barefoot running on harder and softer surfaces
Footwear Sci, 5 (2013), pp. 39-44
Copyright © 2017. FC Barcelona
Apunts Medicina de l'Esport (English Edition)

Subscribe to our Newsletter

Article options
Tools
Cookies policy
To improve our services and products, we use cookies (own or third parties authorized) to show advertising related to client preferences through the analyses of navigation customer behavior. Continuing navigation will be considered as acceptance of this use. You can change the settings or obtain more information by clicking here.

Are you a health professional able to prescribe or dispense drugs?