ArticlePDF Available

Abstract and Figures

Content may be subject to copyright.
Running Barefoot or in
Minimalist Shoes:
Evidence or Conjecture?
Carey Rothschild, PT, DPT, CSCS
Program in Physical Therapy, University of Central Florida, Orlando, Florida
Running has become an increas-
ingly popular and efficient way
to achieve fitness and promote
long-term exercise. Running and jog-
ging participation in the United States
has increased 10.3% in the past 2 years,
totaling 35.5 million, according to the
National Sporting Goods Associa-
tion (
100521.pdf ). Participation varies from
recreational to competitive, with race
distances ranging from the 5K to the
marathon. Other people may partici-
pate in running for fun or as a functional
part of their lives or occupations (43).
Footwear has evolved considerably over
the years humans have been running.
Early humans either went barefoot or
wore protective and insulating foot
coverings in the form of sandals or
moccasins (42). Advances in footwear
offered improved traction and perfor-
mance and eventually provided support
and cushioning for the foot. Changes in
construction methods and the availabil-
ity of new materials allowed for
improved breathability, comfort, and
durability (42). The current selection of
running shoes offers a vast array of
stability and cushioning features from
numerous shoe brands.
Despite the advances in shoe technol-
ogy providing for increased cushioning
and motion control, there has been
a recent movement promoting running
barefoot or in light ‘‘minimalist’’ shoes.
Advocates of barefoot running believe
that returning to the way our primal
ancestors ran may result in fewer
running-related injuries. The Barefoot
Runners Society, founded in the
United States, has nearly 2000 mem-
bers internationally and is growing
annually. Barefoot running has been
the topic of numerous books, journal
and magazine articles, as well as news
reports. The purpose of this article is to
discuss the biomechanical differences
between barefoot and shod (wearing
shoes) running and to present a pre-
paratory exercise program for the
runner interested in transitioning from
a traditional running shoe to the
barefoot style. Focus will be placed
on preparing the lower extremity for
the demands required by the biome-
chanics of barefoot running. The pro-
posed benefits and risks to barefoot
running will briefly be discussed as will
an appraisal of the available evidence.
Running gait is comprised of 2 basic
periods: stance and swing (8). Stance
begins when the foot is in contact with
the ground, whereas the swing phase
begins as the foot moves into toe-off
and prepares to leave the ground.
Stance makes up approximately 40%
of the cycle and swing comprises the
other 60% (7). Running gait is charac-
terized by single-leg support and dou-
ble-leg float periods. During walking,
however, one foot is always in contact
with the ground. The impact landing of
one foot from an unsupported position
during running results in transmission of
forces as much as 5 times the body
weight throughout the lower limb (3).
The lower extremity must control and
absorb these impact forces efficiently to
avoid potential injury.
The stance period of running gait can
further be divided into initial contact,
midstance, and toe-off. From initial
contact to midstance, the lower ex-
tremity actively decelerates the for-
ward-swinging leg and passively
absorbs the shock of ground reaction
forces. In midstance, the foot makes full
contact with the ground and body
weight begins shifting from the rear-
foot to the forefoot. From midstance to
toe-off, there is a relative lengthening
of the lower extremity with concentric
muscle contraction of the hip and knee
extensors to prepare the foot for the
barefoot running; shod running; running
training; minimalist shoe
VOLUME 34 | NUMBER 2 | APRIL 2012 Copyright ÓNational Strength and Conditioning Association
propulsive push-off, in which the
weight is shifted to the toes and the
foot leaves the ground (3). The swing
period of gait can be further divided
into initial swing, midswing, and ter-
minal swing. During initial swing
and midswing, the foot advances for-
ward in the air and in terminal swing
positions itself for heel strike and
weight acceptance.
Running gait has been described as
a spring-mass system of the leg in
which the joints of the lower extremity
lower the center of mass and absorb
energy much like a spring compresses.
This occurs during the stance phase of
running. The energy absorption is
quickly followed by energy generation
as the limb moves into extension,
similar to the recoil of a spring, allow-
ing for propulsion during the toe-off
phase (10,11). The longitudinal arch of
the foot has been described as an
‘‘impact dampening structure’’ during
the loading (stance) phase of the gait
cycle (32). With each foot strike, the
lower limb endures significant impact
force to the musculoskeletal structures.
The impact at landing is created
through collision of the shoe, foot,
and lower leg mass. Ground contact
style and cadence also affect the impact
imposed on the lower extremity at
landing. The way in which a runner
absorbs and generates energy at each
foot strike differs in barefoot and shod
running because of variations in bio-
mechanics. Knowledge of these key
differences will aid the strength and
conditioning professional in preparing
runners interested in transitioning to
barefoot running.
One primary difference between run-
ning barefoot and in shoes is noted at
the foot during the initial contact
phase. The barefoot running tech-
nique uses a midfoot to forefoot
striking pattern when compared with
a rearfoot heel strike pattern of the
shod runner (Figure 1) (7,21,36). This
foot striking position results in a short-
er stride length and a higher step
frequency (cadence) in barefoot run-
ners. These stride differences may
possibly reduce initial impact forces
by allowing higher preactivation of
plantar flexors before braking at im-
pact (9). The higher preactivation of
the gastrocnemius and soleus de-
creases impact forces by anticipating
the shock with landing. The foot
switches to a forefoot strike and
allows for the ankle plantar flexors
to eccentrically lower the body in
a more controlled manner (9). Lower
peak torques at the hip, knee, and
ankle have also been reported in
barefoot versus shod running, most
prominently at the hip and knee (2).
Ultimately, barefoot runners demon-
strate decreased ground contact time,
flight time, and stride duration
because of the higher cadence
(2,7,21,36). This increased cadence
reduces step length, produces less
vertical excursion of the center of
mass, and reduces braking impulse
and impact transient forces. In addi-
tion, an increased step rate of less than
10% does not alter metabolic costs
and reduces impact load on the body
because of the reduced vertical center
of mass velocity at landing (16).
The flatter foot placement of the
barefoot style at contact results from
a larger plantar flexion range of motion
at the ankle. This causes a more vertical
position of the lower leg and results in
a larger amount of knee flexion to
soften the impact load (7). An overall
greater joint excursion at the ankle has
also been identified when barefoot,
suggesting that the ankle absorbs
impact as well (36). The flatter foot
position also limits pressure at the heel,
where sensation of mechanical inputs
and pain is well established in the
foot sole (7). It should be noted, how-
ever, that calcaneal and tibial move-
ment patterns do not differ substantially
between barefoot and shod running
despite the increased range of motion
seen at the ankle (37).
Another key difference found when
running barefoot versus in shoes
involves the proprioceptive ability of
the foot. Barefoot running allows for
direct contact with the ground and for
increased proprioceptive feedback.
The glabrous epithelium of the plantar
surface of the foot is equipped to
withstand potential abrasive injuries
when barefoot because of its higher
pain threshold and ability for sensory
feedback (31). It has been demon-
strated that approximately 600%
greater abrading loads are required
to reach pain threshold in the plantar
skin of the foot when compared with
hairy skin of the thigh (26). The
sensory feedback from the sole of
the foot activates a series of muscle
contractions in the intrinsic foot
musculature that allows for shock
absorption and diminishes impact
transmission (32). A well-trained foot
disperses pressure to a wider area,
functionally avoiding injury. Barefoot
running removes the external passive
support of a shoe and replaces it with
internal active support by the foot
musculature. However, untrained foot
muscles rely heavily on the support
provided by a shoe.
Running in shoes, however, offers
several advantages that barefoot run-
ning does not. The shoe functions to
protect the plantar surface of the foot
from harmful terrain, extreme weather
conditions, and infectious agents.
Additional functions of the shoe
include providing for motion control,
Figure 1. Types of foot strikes.
Strength and Conditioning Journal | 9
cushioning, stabilization, shock distri-
bution and traction between foot and
the ground (5,26). These shoe design
factors aid in decreasing the high
impact forces of a rearfoot heel strike
at initial contact (5,26). The wearing
of shoes and shoe inserts while
running has also been associated with
reduced impact loading rate and
reduced latency between the maxi-
mum external force and internal forces
of the lumbar musculature (27). Thus,
going barefoot may result in both an
increase in puncture wounds to the
foot as well as overuse of muscles,
tendons, and ligaments throughout
the lower extremity and low back.
The additional cumulative loading
that results from the increased step
rate and forefoot striking pattern
when barefoot could also be consid-
ered as a potential source for injury,
such as metatarsal strains and stress
fractures (22). Although case reports
cannot be generalized, 2 cases of
metatarsal stress fracture have been
documented in runners who have
adopted training in footwear simulat-
ing the barefoot condition (14).
Running performance may be impa-
cted by the wearing of shoes versus
running barefoot. Heart rate and relative
be significantly lower in the barefoot
condition (15). When running barefoot
over ground or on a treadmill, the
associated oxygen cost has been found
to be 5.7% lower than while running
shod (15). It has been found that at 70%
of _
max pace barefoot running is
more economical than running shod,
both overground and on a treadmill
(15). Additional studies have found
maximum oxygen uptake values to be
1.3% lower when running barefoot than
when running in shoes (36). More than
a 10% increase in step rate has been
associated with an increased relative
perceived exertion; however, no signif-
icant increase in oxygen consumption
or heart rate ensued (16). These findings
suggest that running barefoot is more
efficient than shod running. Future
research is needed to determine the
effects of barefoot running on compet-
itive performance.
A shod runner may first opt to run in
a ‘‘minimalist’’ shoe before making the
full transition to barefoot running. A
popular minimalist shoe that has been
studied in the literature is the Vibram
FiveFinger (Vibram SpA, Albizzate,
Italy). Research reports that the min-
imalist shoe may offer similar bio-
mechanics as running barefoot,
including a forefoot striking pattern,
lower ground contact time, higher step
rate, and lower peak impact forces
compared with the traditional running
shoe (36). The minimalist shoe effec-
tively mimics barefoot conditions
while providing small amount of pro-
tection, yet still sits between foot and
the ground and may desensitize and
weaken the foot intrinsics (36). The use
of minimalist shoes, however, has been
considered a possible causative factor
for stress injury to the metatarsals. This
may be because of the need for gait
alterations from a heel strike pattern to
a midfoot striking pattern when run-
ning in the minimalist shoes (14).
Nevertheless, use of the minimalist
shoe may prove to be useful in the
overall transition to barefoot running.
It should be noted that not all runners
may be candidates for the barefoot
running technique. Numerous anatom-
ical factors have been associated with
running injury, including cavus (high-
arch) foot, leg length discrepancy, and
muscle weakness (4,20,25,38). Specifi-
cally, weakness of the hip abductors
and hip flexors has been associated
with running-related injury, including
iliotibial band syndrome (12,25). Struc-
tural abnormalities in the lower
extremity may lead to biomechanical
problems during the running gait cycle.
Additionally, runners with diminished
sensation in the foot as seen in peri-
pheral neuropathy are not good can-
didates for barefoot activity because of
the loss of protective sensation. A
thorough evaluation of lower extremity
strength and gait biomechanics should
be conducted before transitioning to
the barefoot style of running. Careful
preparation and a gradual pace should
be implemented when transitioning
a runner to the barefoot technique.
Various sources have presented transi-
tion to barefoot running programs.
Certainly, the transition should be
gradual and over a period of no less
than 4–8 weeks because muscular
adaptation to training accounting for
strength gains requires this period
(23,33). In addition to strengthening
exercises for core and hip musculature,
an evidence-based preparation program
should consist of activities and exercises
that target the key biomechanical differ-
ences the barefoot runner will experi-
ence when compared with being shod
(Table 1). These key differences include:
plantar sensitivity adaptation, foot
strike pattern and related changes in
stride rate and length, lower extremity
proprioceptive ability, ankle joint flexi-
bility, intrinsic foot strength, and ecc-
entric strength of the lower limb to
control impact forces. Learning the
barefoot style, namely, a reduced heel
strike, is fundamental in the transition to
barefoot running.
Because of the high concentration of
sensory receptors on the plantar sur-
face of the foot, sensitivity adaptation
in the form of increased barefoot
activity should be the first component
of the transition to a barefoot running
program. Suggested mechanisms to
facilitate the foot’s adaptation include
increasing total barefoot activity, walk-
ing both indoors and outdoors with
bare feet, running indoors with bare
feet, and eventually running barefoot
outdoors on soft surfaces followed by
harder surfaces (32). Adaptations to
the plantar skin will take 3–4 weeks of
barefoot running at 30 minutes daily
before an increased velocity in running
speed will be tolerated (31).
Because the foot strike pattern of the
barefoot technique is located more at
the forefoot to midfoot, drills should be
incorporated to enhance and learn the
Running Barefoot or in Minimalist Shoes
proper landing techniques and to
reinforce the resulting increase in stride
frequency with subsequent shorter step
length (36). Barefoot running drills done
in the grass using a metronome at a 5–
10% faster cadence could be beneficial
in training a runner for the demand of
increased stride rate when barefoot (16).
Drills should focus on the increased step
frequency combined with a shorter step
length while maintaining a forefoot
landing (Figure 2). The author recom-
mends aiming for a cadence close to
180 steps per minute in accordance with
the high step rate found in the barefoot
Because of the increased neuromus-
cular control required by the lower
limb in controlling impact forces,
proprioceptive exercises should be
incorporated into the preparatory
transition program. Exercises that
have been cited in the literature to
improve lower limb proprioception
include: ankle range of motion exer-
cises on fixed surfaces followed by
wobble board with eyes opened and
closed; single-leg stance activities using
an ankle disc (Figure 3) (34), balance
board (41), or mini-trampoline (19);
and static kicks using resistive bands
(1) (Figure 4). Performance of these
activities with increased weight-
bearing through the forefoot should
train the foot more specifically for the
forefoot loading used in barefoot
As an increased ankle joint excursion
is required by the barefoot runner,
flexibility exercises to improve ankle
range of motion should be performed.
Traditional calf stretching against
a wall or off the edge of a step may
be performed (Figure 5). Focus should
be placed on maintaining a neutral
arch throughout the duration of the
stretch. The stretch is typically held
for 30 seconds and repeated 3–5 times
for each leg. Additionally, propri-
oceptive neuromuscular facilitation
techniques, including contract–relax
and agonist-contract stretching, have
been found to be a useful training
modality for increasing ankle joint
range of motion (29).
Table 1
Preparatory activities for barefoot running
Barefoot activity Barefoot walking indoors
Barefoot walking outdoors
Barefoot running indoors
Barefoot running outdoors—progress from grass to asphalt
Running form drills (Figure 2) Forefoot striking
Increased cadence
Shorter step length
Proprioceptive exercises (Figures 3, 4) Single-leg stance
Single-leg stance on ankle disc/wobble board
Single-leg stance with resistive band
Flexibility exercises (Figure 5) Calf stretching against wall
Calf stretching off the edge of a step
PNF calf stretching
Strengthening exercises (Figures 6, 7) Foot intrinsics
Plyometric activities (Figures 8–10) Hops (single-leg forward hops, single-leg hurdle hops)
Jumps (squat jumps, split scissor jumps, depth jumps, double/single-leg hurdle jumps)
Bounding in horizontal and vertical planes (double-leg bounds, alternate leg bounds)
Figure 2. Running form drill. Skipping
with a focus on forefoot
Strength and Conditioning Journal | 11
Because of the apparent weakening of
the foot intrinsics that occurs in the
habitually shod runner, strengthening
of these muscles is a critical component
of a transitional training program.
Traditional exercises, such as towel
curls, picking up objects, single-limb
balance activities, and the short-foot
exercise, have been used to strengthen
the intrinsic foot musculature (18,24).
The towel curl exercise is used to
strengthen the flexor digitorum longus
and brevis, lumbricales, and flexor
hallucis longus (18). The short-foot
exercise, however, has been found to
be superior to the traditional toe curl
exercise in activating the abductor
hallucis, the largest foot intrinsic mus-
cle found most medial within the first
layer of the foot intrinsic muscles
(Figure 6) (18). This muscle contributes
to increased arch height and helps to
control pronation when activated. The
muscle had been found to be more
activated while performing the short-
foot exercise in the 1-legged standing
position versus seated (18). To effec-
tively perform this exercise, the patient
attempts to draw the heads of the
metatarsals toward the calcaneus while
avoiding extraneous motion. Tactile
input can be provided by the clinician
and verbal reinforcement to avoid toe
curling (Figure 7).
As the knee and ankle become more
responsible for controlling the impact
loading during barefoot striking,
lower extremity plyometric exercises
should be incorporated into the
training program to prepare the lower
limb for this activity. Before beginning
eccentric lower extremity training,
however, the runner should have
sufficient strength in the core and
hip musculature to provide proximal
stability for the distal extremity.
Although the recommended plyo-
metric exercises have been studied
in shoes, the authors recommend that
the activities be done barefoot to
better prepare for barefoot running.
Beginning these exercises on a mini-
trampoline allows for the stretch-
shortening cycle mechanism to pro-
duce greater maximum leg power and
acts to reduce the impact forces on
the body during jump training, thus
reducing the potential for injury (6).
Plyometric training exercises include
hops, jumps, bounding in horizontal
and vertical planes, squat jumps
(Figures 8, 9), split scissor jumps,
double-leg bounds, alternate leg
bounds (Figure 10), single-leg for-
ward hops, depth jumps, double-leg
hurdle jumps, and single-leg hurdle
hops. These specific plyometric ac-
tivities have been found to improve
distance running performance
(28,35). The athlete may progress to
performing these activities on field
grass and progressively harder surfa-
ces. General progression guidelines
Figure 3. Single-leg stance propriocep-
tive exercise while standing
on an ankle disc.
Figure 4. Single-leg stance propriocep-
tive exercise with opposite
lower extremity kicks using
resistive band.
Figure 5. Standing calf stretch.
Running Barefoot or in Minimalist Shoes
for plyometric activities should be
followed while monitoring for muscle
soreness and skin integrity of the bare
Once a runner has prepared the lower
extremity for the demands of barefoot
running through preparatory exercises,
the runner should be ready to increase
mileage while barefoot or in minimalist
shoes. Some runners may exclusively
run barefoot or in minimalist shoes,
whereas others may opt to train
barefoot only for certain types of runs
and shod for others. Some may choose
only to perform running drills barefoot
and continue to run in shoes for
training runs. Ultimately, the runner
will need to decide what his or her
goals are for implementing barefoot
No studies to date have demonstrated
the safest or most effective method
for implementing a barefoot running
program (17). General recommenda-
tions advise for a very gradual in-
crease in barefoot running activity for
successful implementation to allow
for musculoskeletal and cutaneous
adaptation (17). The barefoot running
transition program begins with bare-
foot activity including daily walking
and the aforementioned preparatory
exercises. The author recommends
running no more than a quarter mile
to 1 mile every other day during the
first week of barefoot running. This
may be performed independently or
added onto a regular training run. For
example, a runner may do 3 miles of
shod running on the road and then
a quarter mile barefoot on a grassy
field. When increasing the training
distance, it is recommended to in-
crease barefoot running by no more
than 10% per week (Table 2). Should
muscles remain sore, mileage should
not be increased but rather main-
tained instead for an additional week.
In our experience, sore and tired
muscles are to be expected; however,
careful attention should be paid to
bone, joint, or soft tissue injury
because this may signal the presence
of injury. A grassy field or a rubber-
ized track may be the preferred
surfaces to begin running barefoot
or in minimalist shoes. This could
then be followed by smooth paved
trails and roads while paying careful
foot. Patience will be required be-
cause it may take months to make the
transition to a full-time barefoot
Several key biomechanical differences
between barefoot and shod running
have been identified in the literature
(Table 3). These differences are pri-
marily found during the stance phase
of gait and directly impact the step
length and step frequency of the
running cycle. Running barefoot uses
a forefoot to midfoot landing and,
thus, creates a shortened step length
with resulting increase in step fre-
quency. In contrast, initial contact
while shod is at the heel and results
in a longer step length and reduced
step frequency. Additionally, the pro-
prioceptive ability of the foot is greater
when barefoot because the foot makes
direct contact with the ground. This
may allow the foot musculature to
react to the ground impact forces and
to control shock absorption. How-
ever, the shoe allows for the pro-
tection, cushioning, stabilization, and
Figure 6. Short-foot exercise. Drawing the heads of the metatarsals toward the
calcaneus without curling the toes.
Figure 7. Tactile cueing for the short-foot exercise.
Strength and Conditioning Journal | 13
shock absorption that barefoot run-
ning does not. The forefoot contact,
frequency, and increased propriocep-
tion while running barefoot may
contribute to reduced impact forces
and decreased injury rates in the lower
Despite the lack of research studies
comparing injury rates in barefoot
versus shod populations in devel-
oped countries, it is proposed that
runners using the barefoot running
style will encounter less impact-re-
lated injuries. Yearly incidence of
long-distance running injuries in
recreational and competitive runners
is high with variability ranging from
19.4 to 79.3% (39). Two of the most
recent studies found incidence rates
of 54.85 and 59%, more than half of
runners (30,40). Injury rates are as
high as 90% in runners training for
a marathon (13). Higher training
mileage per week in male runners
and a history of previous running
injury have been identified as risk
factors for injury (39). Running
injuries typically manifest in the
lower extremity and can affect the
bone, ligaments, tendons, and
muscles. Frequently reported
running injuries include ankle sprain,
plantar fasciitis, tibial stress syndrome/
shin splints, iliotibial band tendinitis,
Achilles tendinitis, and peripatellar pain
(13,39). Runners are particularly inter-
ested in learning ways to reduce the
possibility of injury. Barefoot activity
has been found to spare the plantar
fascia from impact forces as the foot
intrinsic muscles activate to control
impact loads (32). In addition, where
shod and unshod populations coexist,
the injury rate is higher in the shod
population (32). Unshod lifestyles are
also associated with a lower frequency
of lower extremity osteological pathol-
ogy, such as bony lesion, osteophyte
formation, and fracture (44).
The recent resurgence of barefoot
running may be a result of the growing
belief that barefoot running is better
for the body than using supportive
footwear. The expectation is that injury
rates will decrease as runners encoun-
ter lower impact-related forces when
barefoot. To date, most supportive
reports for barefoot running have been
anecdotal. Future research is indicated
to examine the effects of barefoot
running on both injury reduction and
Numerous studies demonstrate the
profound biomechanical gait differ-
ences seen in those running bare-
foot compared with shod individuals.
Figure 8. Squat jump, start position.
Figure 9. Squat jump, end position.
Figure 10. Alternate leg bounding.
Running Barefoot or in Minimalist Shoes
These differences should be accounted
for in preparing a runner for the
barefoot style of running. Several
studies support the use of barefoot
running for the proposed advantages
of improved sensory feedback and
proprioception and reduced impact
forces; however, no evidence exists
that these factors result in reduced
injuries or improved performance.
Some evidence exists for improved
foot intrinsic strength in the foot
musculature and improved physiolog-
ical economy when running barefoot,
reduction or improved performance.
Clearly, much more research is
needed on barefoot running, espe-
cially in the areas relating to injury
rates and performance. Although an
absence of evidence does not imply an
evidence of absence, those individuals
involved in exercise prescription must
recognize the difference between
evidence-based information and that
which is based on an ad novitatum
Nevertheless, runners may be curious
to experiment with the barefoot style
of running for the purported benefits
of injury reduction and performance
enhancement. Making the transition
from shod to barefoot running
should be gradual and ideally super-
vised by a knowledgeable strength
and conditioning professional. Carefully
selected training exercises, such as
those outlined in this article, may
prepare the runner for the new
demands placed on the barefoot
lower extremity and should minimize
adverse effects during the transitional
period. Sufficient patience and time
may be required to adapt to the new
style because pain or discomfort may
be present due to running in a com-
pletely different way. New barefoot
runners should be prepared to ini-
tially run slower while barefoot
because of the change in running
form and increased need for atten-
tion to the ground. Continued super-
vision and guidance from the
strength and conditioning pro-
a successful transition to the bare-
foot style.
Table 2
Sample barefoot running progression program
Weeks 1–4 Lower extremity preparatory exercises: 2–3 times per week
Barefoot activity including walking: 30 minutes daily
Weeks 5–6 Barefoot running ¼ mile–1 mile: 2–3 times per week
On a surface such as a grassy field or rubberized track
Weeks 7–8 Barefoot running increase by 10% to
mile–1¼ miles: 2–3 times per week*
On a surface such as a grassy field or rubberized track
Weeks 9 and beyond Barefoot running increase by an additional 10% to ½ mile–1½ miles: 2–3 times per week
Progress to smooth paved surfaces if desired
*Do not progress mileage if soreness persists.
Table 3
Key differences between barefoot and shod running
Barefoot running Shod running
Initial contact Midfoot to forefoot strike Rearfoot (heel) strike
Step length Shorter Longer
Step frequency Higher Lower
Proprioception Increased due to direct foot contact Decreased due to barrier of the shoe
Foot protection No Yes
Foot control Intrinsic via musculature Extrinsic via shoe features for stabilization
Strength and Conditioning Journal | 15
Rothschild is
a Physical Thera-
pist and Instructor
in the Program in
Physical Therapy
at the University
of Central Florida.
1. Baltaci G and Kohl HW. Does
proprioceptive training during knee and
ankle rehabilitation improve outcome?
Phys Ther Rev 8: 5–16, 2003.
2. Braunstein B, Arampatzis A, Eysel P, and
Bruggemann GP. Footwear affects the
gearing at the ankle and knee joints during
running. J Biomech 43: 2120–2125,
3. Brotzman S and Wilk KE. Clinical
Orthopedic Rehabilitation. Philadelphia,
PA: Mosby, 2003. pp. 513.
4. Brunet ME, Cook SD, Brinker MR, and
Dickenson JA. A survey of running injuries
in 1501 competitive and recreational
runners. J Sports Med Phys Fitness 30:
307–315, 1990.
5. Butler RJ, Hamill J, and Davis I. Effect of
footwear on high and low arched runners’
mechanics during a prolonged run. Gait
Posture 26: 219–225, 2007.
6. Crowther RG, Spinks WL, Leicht AS, and
Spinks CD. Kinematic responses to
plyometric exercises conducted on
compliant and noncompliant surfaces.
J Strength Cond Res 21: 460–465, 2007.
7. De Wit B, De Clercq D, and Aerts P.
Biomechanical analysis of the stance
phase during barefoot and shod running.
J Biomech 33: 269–278, 2000.
8. Dicharry J. Kinematics and kinetics of gait:
From lab to clinic. Clin Sports Med 29:
347–364, 2010.
9. Divert C, Mornieux G, Baur H, Mayer F, and
Belli A. Mechanical comparison of barefoot
and shod running. Int J Sports Med 26:
593–598, 2005.
10. Farley CT, Glasheen J, and McMahon TA.
Running springs: Speed and animal size.
J Exp Biol 185: 71–86, 1993.
11. Farley CT and Gonzalez O. Leg stiffness
and stride frequency in human running.
J Biomech 29: 181–186, 1996.
12. Fredericson M, Cookingham CL,
Chaudhari AM, Dowdell BC, Oestreicher N,
and Sahrmann SA. Hip abductor weakness
in distance runners with iliotibial band
syndrome. Clin J Sport Med 10: 169–175,
13. Fredericson M and Misra AK. Epidemiology
and aetiology of marathon running injuries.
Sports Med 37: 437–439, 2007.
14. Giuliani J, Masini B, Alitz C, and Owens BD.
Barefoot-stimulating footwear associated
with metatarsal stress injury in 2 runners.
Orthopedics 34: e320–e323, 2011.
15. Hanson NJ, Berg K, Deka P, Meendering
JR, and Ryan C. Oxygen cost of running
barefoot vs. running shod. Int J Sports Med
32: 401–406, 2011.
16. Heiderscheit BC, Chumanov ES,
Michalski MP, Wille CM, and Ryan MB.
Effects of step rate manipulation on joint
mechanics during running. Med Sci Sports
Exerc 43: 296–302, 2011.
17. Jenkins DW and Cauthon DJ. Barefoot
running claims and controversies: A review
of the literature. J Am Podiatr Med Assoc
101: 231–246, 2011.
18. Jung DY, Kim MH, Koh EK, Kwon OY,
Cynn HS, and Lee WH. A comparison in
the muscle activity of the abductor hallucis
and the medial longitudinal arch angle
during toe curl and short foot exercises.
Phys Ther Sport 12: 30–35, 2011.
19. Kidgell DJ, Horvath DM, Jackson BM, and
Seymour PJ. Effect of six weeks of dura
disc and mini-trampoline balance training
on postural sway in athletes with functional
ankle instability. J Strength Cond Res 21:
466–469, 2007.
20. Korpelainen R, Orava S, Karpakka J, Sirra
P, and Hulkko A. Risk factors for recurrent
stress fractures in athletes. Am J Sports
Med 29: 304–310, 2001.
21. Lieberman DE, Venkadesan M,
Werbel WA, Daoud AI, D’Andrea S,
Davis IS, Mang’eni RO, and Pitsiladis Y.
Foot strike patterns and collision forces in
habitually barefoot versus shod runners.
Nature 463: 531–535, 2010.
22. Milgrom C, Finestone A, Sharkey N, and
Hamel A. Metatarsal strains are sufficient to
cause fatigue during cyclic overloading.
Foot and Ankle 23: 230–235, 2002.
23. Moritani T and deVries HA. Neural factors
versus hypertrophy in the time course of
muscle strength gain. Am J Phys Med 58:
115–130, 1979.
24. Newsham KR. Strengthening the intrinsic
foot muscles. Athl Ther Today 15: 32–35,
25. Niemuth PE, Johnson RJ, Myers MJ, and
Thieman TJ. Hip muscle weakness and
overuse injuries in recreational runners.
Clin J Sport Med 15: 14–21, 2005.
26. Nigg BM and Segesser B. Biomechanical
and orthopedic concepts in sport shoe
construction. Med Sci Sports Exerc 24:
595–602, 1992.
27. Ogon M, Aleksiev AR, Spratt KF, Pop MH,
and Saltzman CL. Footwear affects the
behavior of low back muscles when jogging.
Int J Sports Med 22: 414–419, 2 001.
28. Paavolainen L, Ha
¨kkinen K, Hamalainen I,
Nummela A, and Rusko H. Explosive-
strength training improves 5-km running
time by improving running economy and
muscle power. J Appl Physiol 86:
1527–1533, 1999.
29. Rees SS, Murphy AJ, Watsford ML,
McLachlan KA, and Coutts AJ. Effects of
proprioceptive neuromuscular facilitation
stretching on stiffness and force-producing
characteristics of the ankle in active
women. J Strength Cond Res 21:
572–577, 2007.
30. Ristolainen L, Heinonen A, Turunen H,
¨m H, Waller B, Kettunen JA, and
Kujala UM. Type of sport is related to injury
profile: A study on cross country skiers,
swimmers, long-distance runners and
soccer players. A retrospective 12-month
study. Scan J Med Sci Sports 20:
384–393, 2010.
31. Robbins S, Gouw GJ, McClaran J, and
Waked E. Protective sensation of the
plantar aspect of the foot. Foot Ankle 14:
347–352, 1993.
32. Robbins SE and Hanna AM. Running-
related injury prevention through barefoot
adaptations. Med Sci Sports Exerc 19:
148–156, 1987.
33. Sale DG. Neural adaptation to resistance
training. Med Sci Sports Exerc 20:
S135–S145, 1988.
34. Sheth P, An K-N, Laskowski ER, and Yu B.
Ankle disk training influences reaction times
of selected muscles in a simulated ankle
sprain. Am J Sports Med 25: 538, 1997.
35. Spurrs RW, Murphy AJ, and Watsford ML.
The effect of plyometric training on
distance running performance. Eur J Appl
Physiol 89: 1–7, 2003.
36. Squadrone R and Gallozzi C. Biomechanical
and physiological comparison of barefoot
and two shod conditions in experienced
barefoot runners. J Sports Med Phys Fitness
49: 6–13, 2009.
37. Stacoff A, Nigg BM, Reinschmidt C,
van den Bogert AJ, and Lundberg A.
Tibiocalcaneal kinematics of barefoot
versus shod running. J Biomech 33:
1387–1395, 2000.
38. Thijs Y, Tiggelen DV, Roosen P, De Clercq
D, and Witvrouw E. A prospective study on
Running Barefoot or in Minimalist Shoes
gait-related intrinsic risk factors for
patellofemoral pain. Clin J Sport Med 17:
437–445, 2007.
39. van Gent RN, Siem D, van Middelkoop M,
van Os AG, Bierma-Zeinstra SMA, and
Koes BW. Incidence and determinants of
lower extremity running injuries in long
distance runners: A systematic review. Br J
Sports Med 41: 469, 2007.
40. Van Middelkoop M, Kolkman J,
Van Ochten J, Bierma-Zeinstra SMA,
and Koes B. Prevalence and incidence of
lower extremity injuries in male marathon
runners. Scan J Med Sci Sports 18:
140–144, 2008.
41. Verhagen E, Bahr R, Bouter L, Twisk J,
van der Beek A, and van Mechelen W.
The effect of a proprioceptive balance
board training program for the prevention
of ankle sprains: A prospective
controlled trial. Am J Sports Med 32:
1385, 2004.
42. Werd MB and Knight EL. Athletic
Footwear and Orthoses in Sports
Medicine. New York, NY: Springer, 2010.
pp. 3–4.
43. Wilk BR, Muniz A, and Nau S. An
evidence-based approach to the
orthopaedic physical therapy:
Management of functional running
injuries. Orthop Phys Ther Pract 22:
213–216, 2010.
44. Zipfel B and Berger LR. Shod versus
unshod: The emergence of forefoot
pathology in modern humans? Foot 17:
205–213, 2007.
Strength and Conditioning Journal | 17
... There is little research on which to assist individuals who desire to transition from traditional MEHRS to MFW. However, a guided transitioning program is recommended (Dicharry, 2012;Rothschild, 2012;Kernozek, et al., 2014;Giandolini, et al., 2013;Douglas, 2013, pgs. 97-105) and runners are advised that an appropriate period of time to transition to minimal footwear should be established (Ryan, et al., 2009;Warne, et al., 2015;Moore, et al., 2015). ...
... Based on individual ankle, great toe, and single-leg characteristics, transition to minimal or barefoot running (Dicharry, 2012;Douglas, 2013). Most research examining differences in running mechanics between barefoot or barefoot-like/minimalist shoes and traditional/modern footwear has been short-term in nature, comparing acute changes in controlled laboratory environments Rothschild, 2012;Kernozek, et al., 2014;Giandolini, et al., 2013;Douglas, 2013, pgs. 97-105). ...
... Factors such as weather conditions or the surfaces used during training were not controlled but contributed to the strength of the study, external validity, since it replicates what runners would experience if they were to transition on their own. The duration of the study and parameters on which the training protocol was established were set in accordance with the available literature (Rothschild, 2012;Kernozek, et al., 2014;Warne, Kilduff, et al., 2014). While kinematic changes were initially observed, future research should examine the effect of the length of transition programs and variations of training protocol variables. ...
Full-text available
Purpose: The study examined the impact of minimalist running shoes on running gait in real-world conditions. Methods: Fourteen recreational runners, who previously ran in traditional running shoes, trained exclusively in minimalist shoes for 4 weeks following a prescribed program. Data were collected while wearing traditional running shoes at the beginning and end of the study, and each week of training in minimalist footwear. Once a week, they ran a specified route while wearing a GPS system that captured data on step frequency, step length, vertical oscillation, and ground contact time. Type of foot strike (rear, mid, or forefoot) was assessed through video analysis. Results: Step length, vertical oscillation, and foot strike pattern showed acute changes when switching footwear, and also gradual changes of the 4 weeks of training. Foot strike pattern changed from primarily rear-foot strike to mid/forefoot strike over four-weeks, but tended to revert to back to the pre-intervention rear-foot pattern when participants returned to wearing traditional shoes. Runners were able to transition to minimalist shoes with limited discomfort by following the training protocol.
... 3 Injury-related factors are improper running shoes, improper training and biomechanical factors. 4 Therefore, to deal with running injuries, comfort and performance running shoes were developed, 5 while barefoot running became popular. 6,7 Why did these two actions become popular in outdoor running? ...
... Besides, barefoot running might provide more sensory information during foot strike. 5 Shoes might reduce the foot sensory information during the stance phase. 53 In addition, the first attempts to run barefoot are usually associated to higher GRF, leading to change foot strike pattern. ...
Full-text available
This study aims to analyze and summarize the biomechanical (kinematics, kinetics and neuromuscular) differences between shod and barefoot running, through a literature review. Searches were conducted for complete articles published between 2013 and November 2018 in the Web of Science, PubMed, Scopus and SPORTdiscus databases. The search terms used were Biomechanics, Kinetics, Kinematics, Electromyography, “Surface Electromyography”; and Unshod, Barefoot, Barefeet and Running. The search resulted in 687 articles; after excluding duplicates and selecting by title, abstract and full text, 40 articles were included in the review. The results show that there are important differences in the biomechanics of running when shod or barefoot. In general, studies indicate that in barefoot running: a) individuals present forefoot or midfoot foot strike patterns, while in shod running the typical pattern is the rearfoot strike; (b) greater cadence and shorter stride length are observed; and (c) there is greater knee flexion, lower peak vertical ground reaction force and greater activation of the medial gastrocnemius. In addition, barefoot runners contact the ground with greater plantar flexion, possibly as a strategy to reduce impact when stepping without footwear. These differences, as well as runners’ individual characteristics, should be considered in the prescription of the barefoot running, in order to minimize injuries resulting from the practice. Level of Evidence II; Review.
... One of the exceptions is Len Tau, one of the two first athletes from Africa to participate in an Olympic Games, who is said to have run barefoot and finished ninth during the third modern Olympic Games, St. Louis, USA, despite the lack of specific training for the race and after being chased off-course by stray dogs [29]. According to Lieberman et al. [46] and Rothschild [49], there is evidence of improved intrinsic foot strength and improved physiological economy when running barefoot, but no evidence for injury reduction or improved performance. Several studies support barefoot running and minimalist shoes for the proposed advantages of improved sensory feedback and proprioception and reduced impact forces [46]. ...
Full-text available
Performance in different athletic activities has continued to improve over time, with some athletes from diverse parts of the world registering new world records from time to time. With stiff competition from athletes from different parts of the world, constant upgrading of sports science based approaches to training and competition are employed to achieve more success. However, some approaches used to improve sports performance may pose ethical concerns and may challenge sports as a concept of celebrating natural human abilities. This book chapter interrogates the factors associated with efforts towards improvement of performance in endurance sports events, with a specific focus on marathon races, and the future implications for training, competition, and the nature of sports. While the interplay between nature and nurture determines the unique psychophysiological responses to training and competition, technological exploits leading to advanced sports products coupled with favourable natural and/or manipulated internal (body) and external environmental conditions will ensure continued improvement in performance. However, there is a need to censor commercial interest as well as safeguard safety and the nature of sports as a medium to celebrate natural human abilities.
... Barefoot and minimal footwear conditions have become popular in recent years due to claims of "natural" foot motion achieved in comparison to conventional athletic footwear [1,2]. Relative to conventional athletic footwear, minimal footwear tends to be constructed using more flexible materials that are lighter in weight and provide less arch support to replicate the barefoot environment while providing some protection [3]. ...
Full-text available
Effects of barefoot and minimal footwear conditions on performance during jumping (i.e., jump displacement) are unclear with traditional group-level studies because of intra- and interindividual variability. We compared barefoot, minimal, and conventional athletic footwear conditions relative to countermovement vertical jump (CMVJ) performance and muscle activation using a single-subject approach. Fifteen men (1.8 � 0.6 m; 84.5 � 8.5 kg; 23.8 � 2.3 y) performed three CMVJ trials in barefoot, minimal, and conventional footwear conditions while ground reaction forces (GRF) and electromyograms of eight lower extremity muscles were recorded. The Model Statistic procedure (� = 0.05) compared conditions for CMVJ displacement, net impulse, durations of unloading, eccentric, and concentric phases, and average muscle activation amplitudes during the phases. All variables were significantly altered by footwear (p < 0.05) in some participants, but no participant displayed a universal response to all variables with respect to the footwear conditions. Seven of 15 participants displayed different CMVJ displacements among footwear conditions. Additional characteristics should be evaluated to reveal unique individual traits who respond similarly to specific footwear conditions. Considerations for footwear selection when aiming for acute performance enhancement during CMVJ tests should not be determined according to only group analysis results. The current single-subject approach helps to explain why a consensus on the effects of barefoot, minimal, and conventional footwear conditions during the CMVJ remains elusive.
... Nowadays, the existing study about barefoot and strength mainly focus on two aspects, which one is to explore the influence of barefoot running on the lower limb and another one is to explore the barefoot application in sports performance [3,10]. For instance, Carey et al [11] reviewed barefoot running studies and pointed that barefoot running could improve foot muscular strength and lead variation in lower-limb kinematic; Villiers [10] explored the influence of barefoot training on ankle stability, agility and speed and suggested that barefoot training could produce positive influence on ankle performance. Although existing biomechanical studies remind the importance of calf strength for shod runner adopting barefoot running; however, the rarely limited study involves the influence of enhancement of calf strength on barefoot running, let alone the influence of the plantar pressure or longer-period resistance training. ...
The purpose of this study was to determine whether enhancement of calf muscular strength can produce influence on plantar pressure in barefoot running. Ten healthy male subjects (age:22±2.5 years, height: 1.76±0.4m, body mass: 65±2.5kg) participate this experiment enduring 8-week strength training adopting by calf raise movement on calf muscle. A medical ultrasonic instrument (Q6, China) was used to observe the variation of calf muscular morphology. A plantar pressure plate ( Novel Emed, Germany) was used to collect the variation of 8-region plantar pressure. After 8-week strength training, a significant increasing trend between pre-and post-strength training in subject`s pinnation angle (PA) of the gastrocnemius was found. Under strength training, there are some significant variations between pre-and post-plantar pressure. The start point of center of pressure (COP) gradually forward (middle foot 80%, forefoot 20%); the peak pressure of subject`s heel foot (HF) significantly lower; the maximal force in second-third metatarsal (M 2-3), medial foot (MF) and HF significantly decrease; the contact area in other toe (OT) significantly increase as well as MF and HF significantly decrease; the time-force integral in M2-3 and HF significantly lower and in MF significantly enhance. These results suggest, the enhancement of calf muscular strength may produce positively influence on beginning transitional process from shod running to barefoot running and is also worth to as a feasible way to recommend. However, the effects of strength straining on plantar pressure do not fully explore and still need to deeply explore own to existing limitations.
... A lot of studies in recent years have been created on barefoot effects on running economy (Hanson et al., 2011), avoiding injuries (Lieberman, 2012) or that it may be a running skill (Tam et al., 2014) and an acceptable training method for coaches who can understand and minimize the risks of barefoot running (Jenkins & Cauthon, 2011). Separate studies are showing different benefits of barefoot running (Williams et al., 2012), but authors of reviews are more cautious about claiming potential benefits or the opposite (Rothschild, 2012). Some authors are emphasizing that there is a lack of high-quality evidence and no conclusions can be made on benefits or risks while running barefoot, in minimalist shoes or shod (Perkins et al., 2014). ...
Full-text available
Many suggest that switching from shod running to barefoot running decreases injury risk and makes running more natural. Scientists have reported biomechanical differences in shod and barefoot running, with a number of differences related to increased injury risk. Our research is focused on investigating the acute differences when switching to barefoot running for the first time. Twenty long distance runners were subjected to an experiment as part of this research. The subjects ran 5 trials across two force plates both in shod and barefoot conditions. The ground reaction force (GRF) was recorded for each subject. The stance time, the initial impact loading rate (LR), the impact maximum (IM), the time when the IM was reached, the thrust maximum, the average vertical GRF, and the decay rate (DR) were calculated from the obtained GRF. The results show that the mean LR and DR were greater by 42.191 BW/s (p=0.006) and 5.922 BW/s (p<0.001) respectively in barefoot running compared to shod running. The mean stance time and the time to IM was greater by 10.15 ms (p=0.013) and 5.00 ms (p=0.017) respectively in shod running compared to barefoot running. IM and LR had a significant correlation in shod running condition only (r=0.842, p<0.001). Both conditions, however, had significant correlation between LR and time to IM (shod: r=-0.646, p=0.002; Bare: r=-0.741, p<0.001). According to our data, the responses of the subjects to barefoot running were not unambiguous and in some cases not less traumatic.
... There are several incidences stated about the transition process from conventional running footwear to minimalist footwear. This process gradually lasts from minimal of a few weeks to several months up to individuals (Hart & Smith, 2008;Rixe, Gallo & Silvis, 2012;Rothschild, 2012;Giandolini, Horvais, Farges, Samozino & Morin, 2013;Fuller, Thewlis, Tsiros, Brown & Buckley, 2015;Chen, Sze, Davis & Cheung, 2016). The results of this study suggested the need for additional studies on the effects of RNW on foot production after transition process from conventional running footwear to minimalist footwear. ...
The purposes of this study were to investigate and compare the range of motion changes and force production of the running footwear with and without windlass enhancing feature and barefoot on lower extremities during late stance phase of running. Fourteen healthy recreational rearfoot male runners (age 20.14+0.66 years, height 171.79+4.66 cm, and body weight 64.56+5.79 kg.) were recruited in the study. The three dimensional movement analysis and force production were collected by Motion analysis system and AMTI force platform, the data were calculated and analyzed by Visual 3D. The participants in barefoot and 2 types of footwear; the running footwear with and without windlass enhancing feature, started to run along the runway with speed at 3.5 m/s (range between 3.33-3.68 m/s) for 3 trials in each condition. The repeated measures Analysis of variance was used to analyzed. A Bonferroni post hoc test was conducted between conditions (p < .01). The results revealed that the ankle movement of barefoot and the running footwear without windlass enhancing feature were significantly different from the running footwear with windlass enhancing feature at the beginning but of barefoot was significantly different from the running footwear with and without windlass enhancing feature at the end of the late stance phase. The forefoot's range of motion of barefoot and the running footwear without windlass enhancing feature were significantly different from the running footwear with windlass enhancing feature but the vertical ground reaction forces of the running footwear with and without windlass enhancing feature were not significantly different. Significant difference was found between the barefoot and the running footwear with windlass enhancing feature in force production. In conclusion, the running footwear without windlass enhancing feature offers more flexible forefoot's movements close to the barefoot but the propulsion is still the same as the running footwear with windlass enhancing feature.
Wearing barefoot-style (minimalist) shoes is suggested as a transition between wearing shoes and barefoot running. Some sources equate wearing Vibram FiveFingers™(VFFs), a brand of barefoot shoes, with running/walking barefoot. Static and dynamic balance exercises are recommended. Little information is available on the effects barefoot shoes may have on dynamic balance. This study's purpose was to examine dynamic balance when participants wore VFFs, athletic shoes, or went barefoot (BF). To test dynamic balance, participants used a modified version of the Star Excursion Balance Test (SEBT), in which the reaching leg followed only three spokes of the test: the anterior, posteromedial and posterolateral. For the timed test, participants touched down as quickly as possible in both directions using all 8 spokes. Thirty participants (ages 24.1+/-3.71 years) without lower extremity injury or experience wearing minimalist shoes were tested using the modified SEBT and a timed test wearing VFFs™, athletic shoes, or BF. Three trials for each footwear were completed for three reaching positions: anterior, posterolateral, posteromedial. The timed test measured (seconds) one counterclockwise and one clockwise direction of the 8-spoke figure. A repeated measures analysis of variance determined if any differences existed between footwear type and studied variables. Anterior reach was significantly greater when wearing shoes than with VFF or BF. Posteromedial reach was greater with shoes than BF. Time trials were not significantly different. Because no difference was found in any measured variables between VFF and BF, the results suggest wearing VFFS™ provided similar dynamic balance as going barefoot.
Background & Purpose: Similarities of barefoot and minimalist running received wide attentions in last two decades. The purpose of this study was determination of barefoot and minimalist running by classification of subjects using mechanical energy and PCA method. Methodology: 99 subjects (47 men and 52 women) ran at 3 and 5 m/s in barefoot, minimalist and regular sport shoe conditions. Mechanical energy of pelvic, thigh, shank and foot calculated in stance phase of running. PCs extracted from PCA that covered 95% variance of original data choose for discriminant analysis. A cross validation technique used to determine the accuracy of classification. Results: The results of this study showed that accuracy of model in discrimination between barefoot and running with regular shoe was 81.8%. Accuracy of discriminant analysis for barefoot-minimalist and minimalist-running shoe was 46% and 70.7% respectively. Conclusion: PCA and classification techniques together could be used to determination similarities and differences of different gait conditions. In addition, minimalist running could mimic barefoot running properly.
Introdução: Os variados momentos da corrida descalça precisam ser melhor esclarecidas do ponto de vista científico. O objetivo desta revisão da literatura foi estudar os efeitos de programas de treinamento de correr descalço em indivíduos corredores ativos. Material e métodos: Buscas nas bases Medline, Cinahl, Sportdiscus, Web of Science, Lilacs e Pedro, com seleção dos artigos por dois avaliadores independentes. A qualidade metodológica foi avaliada pela escala Pedro. Resultados: Foram encontrados cinco ensaios clínicos controlados e dois aleatorizados. A qualidade metodológica dos estudos foi de baixa a moderada, com média de 4,1 pontos. Os estudos incluíram de 12 a 26 participantes, com idade entre 18 e 30 anos, quatro foram realizados com atletas e três com corredores recreacionais. Dentre os sete estudos incluídos, os efeitos dos programas de treinamento de correr descalço encontrados foram: melhora da economia de energia na corrida, alterações cinéticas e cinemáticas em membros inferiores, alteração do padrão de ativação muscular e maior estabilidade do tornozelo. Conclusão: O treinamento de correr descalço promove alterações significativas no padrão biomecânico dos membros inferiores dos indivíduos, que poderiam estar relacionadas a um melhor desempenho e menor número de lesões. Além disso, quando comparados aos efeitos imediatos, os resultados seriam mais significativos quando os indivíduos são submetidos a programas de treinamento para a nova condição.Palavras-chave: corrida, educação física e treinamento, biomecânica.
Full-text available
Although much research has been conducted on the measurement and quantification of knee and ankle proprioception, there are few studies on results of targeted proprioceptive training during rehabilitation in knee and ankle injuries. Proprioceptive training has been hypothesized to increase joint stability through a variety of mechanisms, including muscle strength, kinesthesia, and muscle tone. The purpose of this paper is to comprehensively review and critically appraise the available literature from 1966 to January 2001 in order to examine the evidence concerning the efficacy of proprioceptive training during knee and ankle rehabilitation. Medline was searched using MeSH and textwords for English language articles related to proprioceptive training during knee and ankle rehabilitation published since 1966. Additional references were reviewed from the bibliographies of the retrieved articles. The total number of articles reviewed was 9 and 8 for the knee and ankle, respectively. In reviewing the literature, particular attention was paid to the relative strengths of the different study designs. From these data, the factors associated with effectiveness and the beneficial results of proprioceptive training were examined. For the knee, five of the nine studies evaluated a proprioceptive rehabilitation programme for anterior cruciate ligament (ACL) deficient patients, three studied a training programme in healthy subjects and athletes involved in soccer and gymnastics and one study was on patients suffering from knee pain. The duration of proprioceptive training ranged from 1–52 weeks. Eight studies showed the beneficial effects of proprioceptive training during a knee exercise programme; one study showed that joint position sense in the ACL deficient knees with muscular and proprioceptive training remained unchanged. For the ankle, three studies evaluated patients with functionally instability in the ankle joint. The authors found that improvements in balance performance following a 6-week, 8-week, and 10-week training period appeared to be greater in individuals with previously reported ankle sprains as compared with uninjured participants. Three papers investigated the significance of postural stability in healthy subjects receiving a proprioceptive training programme; one studied joint position sense in gymnasts, and one study looked at postural stability in dancers. Eight studies have been published on the benefits of proprioceptive training during a knee exercise programme and the role of proprioception in the knee joint. Increased joint proprioceptive sense, muscle strength, knee kinesthesia, muscle tone and the decreased risk of ACL injury have suggested that dynamic joint control training may improve stability by improving joint position sense in healthy and injured-knees. The effects of proprioceptive training on muscle reaction times and postural stability have increased during ankle rehabilitation after several weeks. Ankle proprioceptive training has been shown to decrease functional instabilities of the ankle and to decrease the incidence of re-injury. Specific neuromuscular co-ordination training such as dynamic joint control and kinesthetic awareness may be indicated at 3–4 months following rehabilitation.
Full-text available
The purpose of this study was to investigate the oxygen cost of running barefoot vs. running shod on the treadmill as well as overground. 10 healthy recreational runners, 5 male and 5 female, whose mean age was 23.8±3.39 volunteered to participate in the study. Subjects participated in 4 experimental conditions: 1) barefoot on treadmill, 2) shod on treadmill, 3) barefoot overground, and 4) shod overground. For each condition, subjects ran for 6 min at 70% vVO (2)max pace while VO (2), heart rate (HR), and rating of perceived exertion (RPE) were assessed. A 2 × 2 (shoe condition x surface) repeated measures ANOVA revealed that running with shoes showed significantly higher VO (2) values on both the treadmill and the overground track (p<0.05). HR and RPE were significantly higher in the shod condition as well (p<0.02 and p<0.01, respectively). For the overground and treadmill conditions, recorded VO (2) while running shod was 5.7% and 2.0% higher than running barefoot. It was concluded that at 70% of vVO (2)max pace, barefoot running is more economical than running shod, both overground and on a treadmill.
To investigate the effects of simultaneous explosive-strength and endurance training on physical performance characteristics, 10 experimental (E) and 8 control (C) endurance athletes trained for 9 wk. The total training volume was kept the same in both groups, but 32% of training in E and 3% in C was replaced by explosive-type strength training. A 5-km time trial (5K), running economy (RE), maximal 20-m speed ( V 20 m ), and 5-jump (5J) tests were measured on a track. Maximal anaerobic (MART) and aerobic treadmill running tests were used to determine maximal velocity in the MART ( V MART ) and maximal oxygen uptake (V˙o 2 max ). The 5K time, RE, and V MART improved ( P < 0.05) in E, but no changes were observed in C. V 20 m and 5J increased in E ( P < 0.01) and decreased in C ( P < 0.05).V˙o 2 max increased in C ( P < 0.05), but no changes were observed in E. In the pooled data, the changes in the 5K velocity during 9 wk of training correlated ( P< 0.05) with the changes in RE [O 2 uptake ( r = −0.54)] and V MART ( r = 0.55). In conclusion, the present simultaneous explosive-strength and endurance training improved the 5K time in well-trained endurance athletes without changes in theirV˙o 2 max . This improvement was due to improved neuromuscular characteristics that were transferred into improved V MART and running economy.
Recombination processes in antimonide-based materials for thermophotovoltaic (TPV) devices have been investigated using a radio-frequency (rf) photoreflectance technique, in which a Nd–YAG pulsed laser is used to excite excess carriers, and the short-pulse response and photoconductivity decay are monitored with an inductively coupled noncontacting rf probe. Both lattice-matched AlGaAsSb and GaSb have been used to double cap InGaAsSb active layers to evaluate bulk lifetime and surface recombination velocity with different active layer thicknesses. With an active layer doping of 2×1017 cm−3, effective bulk lifetimes of 95 ns and surface recombination velocities of 1900 cm/s have been obtained. As the laser intensity is increased the lifetime decreases, which is attributed to radiative recombination under these high-level injection conditions. Similar measurements have been taken on both TPV device structures and starting substrate materials for comparison purposes. © 1999 American Institute of Physics.
Stress-related changes and fractures in the foot are frequent in runners. However, the causative factors, including anatomic and kinematic variables, are not well defined. Footwear choice has also been implicated in contributing to injury patterns with changes in force transmission and gait analyses reported in the biomechanical literature. Despite the benefits of footwear, there has been increased interest among the running community in barefoot running with proposed benefits including a decreased rate of injury. We report 2 cases of metatarsal stress fracture in experienced runners whose only regimen change was the adoption of barefoot-simulating footwear. One was a 19-year-old runner who developed a second metatarsal stress reaction along the entire diaphysis. The second case was a 35-year-old ultra-marathon runner who developed a fracture in the second metatarsal diaphysis after 6 weeks of use of the same footwear. While both stress injuries healed without long-term effects, these injuries are alarming in that they occurred in experienced male runners without any other risk factors for stress injury to bone. The suspected cause for stress injury in these 2 patients is the change to barefoot-simulating footwear. Runners using these shoes should be cautioned on the potential need for gait alterations from a heel-strike to a midfoot-striking pattern, as well as cautioned on the symptoms of stress injury.
Barefoot running is slowly gaining a dedicated following. Proponents of barefoot running claim many benefits, such as improved performance and reduced injuries, whereas detractors warn of the imminent risks involved. Multiple publications were reviewed using key words. A review of the literature uncovered many studies that have looked at the barefoot condition and found notable differences in gait and other parameters. These findings, along with much anecdotal information, can lead one to extrapolate that barefoot runners should have fewer injuries, better performance, or both. Several athletic shoe companies have designed running shoes that attempt to mimic the barefoot condition and, thus, garner the purported benefits of barefoot running. Although there is no evidence that either confirms or refutes improved performance and reduced injuries in barefoot runners, many of the claimed disadvantages to barefoot running are not supported by the literature. Nonetheless, it seems that barefoot running may be an acceptable training method for athletes and coaches who understand and can minimize the risks.
To compare the muscle activity of the abductor hallucis (AbdH) and the medial longitudinal arch (MLA) angle during toe curl (TC) and short foot (SF) exercises while sitting or in one-leg standing position. Two-way repeated-measures ANOVA was used to analyze the effects of exercise type and position on the muscle activity of the AbdH and the MLA angle. Twenty subjects with normal feet participated in this study. The muscle activity of the AbdH and the MLA angle were measured during TC and SF exercises while sitting or in one-leg standing position. The EMG activity of AbdH in SF exercise was significantly greater than during TC exercise in both exercise postural positions (p < 0.001). During the SF exercise, the EMG activity of the AbdH in the one-leg standing position was significantly higher than that while sitting (p < 0.001). The MLA angle in SF exercise was significantly smaller than during TC exercise in both postural positions (p < 0.001). These results suggest that SF exercise is a more useful strengthening exercise than TC exercise in activating the AbdH muscle.