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Playing Basketball on Wooden and Asphalt Courts-Does Court Surface Affect Foot Loading?


Abstract and Figures

This study aimed to examine the influence of court surface on foot loading when executing typical basketball tasks. Thirteen male basketball players performed three basketball related tasks: Layup, jump shot, and maximal effort sprint on wooden and asphalt courts. In-shoe plantar loading was recorded during the basketball movements and peak force (normalised to body weight) was extracted from eight-foot regions. Perceptions of discomfort at the ankle, knee, and back were surveyed using a 10-cm visual analogue scale. Landing from a layup on the wooden court resulted in elevated peak forces at the hallux (p = 0.022) and lesser toes (p = 0.007) compared with asphalt court. During the sprint acceleration step, higher peak forces were observed at the hallux (p = 0.048) and medial forefoot (p = 0.010) on wooden court. No difference between court surfaces was found for perception ratings at the ankle, knee, or back. These results suggested that players can experience greater impact forces at the toes and medial forefoot when performing basketball tasks on the more compliant wooden court than asphalt courts.
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Kong et al. Int J Foot Ankle 2018, 2:009
Volume 2 | Issue 2
International Journal of
Foot and Ankle
Citaon: Kong PW, Nin DZ, Quek RKK, Chua YK (2018) Playing Basketball on Wooden and Asphalt
Courts-Does Court Surface Aect Foot Loading?. Int J Foot Ankle 2:009.
Accepted: July 18, 2018; Published: July 20, 2018
Copyright: © 2018 Kong PW, et al. This is an open-access arcle distributed under the terms of the
Creave Commons Aribuon License, which permits unrestricted use, distribuon, and reproducon
in any medium, provided the original author and source are credited.
Kong et al. Int J Foot Ankle 2018, 2:009
Open Access
• Page 1 of 9 •
Playing Basketball on Wooden and Asphalt Courts-Does Court
Surface Aect Foot Loading?
PW Kong*, DZ Nin, RKK Quek and YK Chua
Physical Educaon and Sports Science Academic Group, Naonal Instute of Educaon, Nanyang
Technological University, Singapore
*Corresponding author: Pui W Kong, Associate Professor, Physical Educaon and Sports Science Academic Group, Na-
onal Instute of Educaon, Nanyang Technological University, 1 Nanyang Walk, 637616, Singapore, Tel: +65-6219-
6213, E-mail:
This study aimed to examine the inuence of court surface
on foot loading when executing typical basketball tasks.
Thirteen male basketball players performed three basket-
ball-related tasks: Layup, jump shot, and maximal effort
sprint on wooden and asphalt courts. In-shoe plantar load-
ing was recorded during the basketball movements and
peak force (normalised to body weight) was extracted from
eight-foot regions. Perceptions of discomfort at the ankle,
knee, and back were surveyed using a 10-cm visual an-
alogue scale. Landing from a layup on the wooden court
resulted in elevated peak forces at the hallux (p = 0.022)
and lesser toes (p = 0.007) compared with asphalt court.
During the sprint acceleration step, higher peak forces were
observed at the hallux (p = 0.048) and medial forefoot (p =
0.010) on wooden court. No difference between court sur-
faces was found for perception ratings at the ankle, knee, or
back. These results suggested that players can experience
greater impact forces at the toes and medial forefoot when
performing basketball tasks on the more compliant wooden
court than asphalt courts.
Plantar pressure, Layup, Jump shot, Sprinting
exist between the various court surfaces; wooden sur-
faces consist of a supercial layer of beech wood, while
asphalt courts are typically surfaced with a layer of rub-
ber coang for shock absorpon [2]. Among coaches,
PE teachers and players, landing on wooden courts is
generally perceived to be ‘soer’ with lower impact
forces than landing on arcial surfaces. This percep-
on can be partly aributed to the lower sness of
wooden courts which allows them to undergo a greater
extent of deformaon upon impact [3]. Although the
injury stascs for wooden and arcial playing surfac-
es in basketball are not known [4], one simulaon study
has shown that wood resulted in lower landing forces
compared to asphalt grounds [2]. The study, howev-
er, simulated only vercal landing from 300 mm and
modelled the human body as a rigid lower limb. This
simplicaon fails to take into account the natural joint
movements (e.g. knee exion) that occur during land-
ing. Furthermore, basketball players execute many oth-
er impacul movements besides vercal jump landings
[5]. Thus, it is necessary to verify the simulaon study
ndings using an experimental approach.
Previous experimental studies found a higher risk of
knee (anterior cruciate ligament) injury for female team
handball players [6] and traumac injury for female
oorball players [7] on arcial surfaces than wooden
oors, possibly inuenced by shoe-court fricon. The
physical demands of basketball are considerably dier-
ent from those of team handball or oorball, with bas-
ketball players being reported to jump approximately
44 mes and sprint every 39 s in a game [5]. Given that
Check for
Basketball is one of the most played sports in the
world [1]. While professional basketball games are usu-
ally played on indoor wooden courts, asphalt-based
arcial courts are also popular especially for outdoor
sengs given the lower maintenance cost and higher
durability. Schools are oen equipped with both wood-
en and asphalt courts for physical educaon (PE) les-
sons and co-curricular acvies. Structural dierences
• Page 2 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
free from any lower-extremity injuries for six months
prior to the me of study. The procedures were ap-
proved by the Nanyang Technological University Instu-
onal Review Board. Parcipants were informed about
the experimental procedures, potenal benets and
risks, and their rights to withdraw at any point of the
study. Prior to tesng, wrien consent were obtained
from all parcipants.
The experiment took place in an indoor wooden bas-
ketball court and an outdoor asphalt court coated with
All Sport surface (California Products Corporaon, An-
dover, USA). The Novel Pedar-X system (Novel GmbH,
Munich, Germany) with 99 sensors within each insole
was used to measure plantar forces. Two pairs of in-
soles, US size 9.0 and 11.0, were calibrated to 700 kPa
with the Trublu calibraon device (Novel GmbH, Mu-
nich, Germany) according to the manufacturer’s guide-
lines. To avoid the inuence of footwear, the same make
and model of basketball shoes (US size 9.0 or 11.0, Nike
Black Mumba 24, Portland, USA) were used across all
parcipants. Parcipants also wore a new pair of socks
provided by the researchers and used the same ball (Li
Ning B6000, Beijing, China) for all shoong tasks.
Eligible parcipants reported for experimental test-
ing on one occasion. First, they were surveyed on their
playing preferences and habits on wooden and arcial
courts. Next, the wireless Pedar-X device with the in-
soles was aached to the parcipants. Aer ve min-
utes of warm-up using their own rounes, parcipants
proceeded to an assigned basketball court (wooden or
asphalt, presented in a randomized order) for familiar-
izaon with the test tasks. Three typical basketball-re-
lated tasks were selected: 1) Layup; 2) Jump shot, and 3)
Sprint (Figure 1). In-shoe plantar loading was recorded
at 100 Hz while performing these tasks.
Layup (Figure 1a): The layup is the most common-
ly employed technique for scoring during basketball
games [20], and the landing biomechanics of this task
has been evaluated in numerous studies [14-17]. For
consistency, dribbling was prohibited prior to the run-
up and a right-handed layup was performed by all par-
cipants [10,18,19]. A recent study showed that for bas-
ketball layup tasks, a minimum of six to eight trials were
needed to obtain stable peak force of the whole foot
using the Pedar-X system [18]. To ensure that the peak
force data collected were suciently reliable, 10 valid
trials were recorded in the present study. A trial being
considered valid if (i) The shot was successful; (ii) The
ball made contact with the rim; or (iii) The ball made
contact with both the back-board and the rim.
Jump shot (Figure 1b): The jump shot is idened as
an eecve and frequently used shoong technique,
receiving much aenon in biomechanical studies
[17,21]. Parcipants were tasked to perform jump shots
the foot loading during basketball related movements
such as layup and side-cung are considerably higher
than that during running [8], it is crucial to understand
the forces acng on players when execung basketball
skills on dierent playing surfaces. Using a force plat-
form, McClay and colleagues [9] quaned the ground
reacon forces during typical basketball tasks in profes-
sional players and reported elevated forces of up to nine
mes an individual’s body weight upon landing from a
jump. To replicate a more realisc playing surface, Nin,
Lam and Kong, [10] used a wooden-top force plaorm
to measure impact forces during basketball layup, simu-
lated shot blocking, and drop landing tasks. Comparable
force data of such high-impact acvies, however, are
not available for other arcial playing surfaces com-
monly used in basketball.
While tradional force plaorms are useful to quan-
fy the total ground reacon forces [9-11], they are of-
ten limited to laboratory sengs and unable to locate
regional load at specic parts of the foot. Recently,
there has been increasing use of mobile in-shoe plan-
tar measurement systems to gain insights into the foot
loading when execung sports tasks on various playing
surfaces. For example, Ford, et al. [12] compared the
in-shoe loading paerns during cung on natural grass
and synthec turf among male football players. Similar-
ly, Tessu, Ribeiro, Trombini-Souza, and Sacco, [13] ex-
amined foot pressure during running on four dierent
surfaces: Asphalt, concrete, rubber, and natural grass.
Although several studies have reported plantar pres-
sure data on basketball-related tasks [8,14-19], to our
best knowledge, the inuence of basketball court sur-
faces on foot loading remains unknown.
The purpose of this study was, therefore, to inves-
gate the inuence of court surface on foot loading
during typical basketball tasks using an experimental
approach. It was hypothesized that lower forces, meas-
ured using an in-shoe system, would be observed on
wooden courts compared with asphalt courts.
Based on simulaon results reported by Kim, et al.
[2], a very large dierence in peak ground reacon force
between asphalt and wood surfaces were found. Thus,
a large eect size of 0.8 was used in a power analysis
to determine the minimum sample size of 12 (α = 0.05,
power = 0.80, one-tail). To account for potenal drop-
out and technical errors, thirteen healthy basketball
players (age = 23.0 (1.4) years, height = 1.75 (0.05) m,
mass = 68.4 (8.6) kg) were recruited for the study. The
inclusion criteria were 1) Males; 2) University students
who parcipated in the Instute Inter-hall Basketball
Games; 3) Had more than ve years of recreaonal bas-
ketball experience, and 4) Had foot size of US 9.0 or 11.0
measured by a Brannock device. All parcipants were
• Page 3 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
the foot on the same side of the shoong arm (right n =
12, le n = 1). For the sprint, the second (right) step rep-
resenng the acceleraon phase was chosen for anal-
ysis [8,19,22] (Figure 1c). A mask of the eight regions
(hallux, lesser toes, medial, central and lateral fore-
foot, medial and lateral arch, and heel) created using
the Novel Mulmask soware (Novel GmbH, Munich,
Germany) was applied to extract the peak force in each
foot region (Figure 2). The peak force indicates the max-
imal force in one-foot region during one step, and this
variable is commonly used in other studies examining
plantar loading during basketball-related tasks [14-18].
Peak forces were then normalised to parcipants’ body
weight (BW). An average value of all valid trials for each
movement was used for subsequent analysis.
Stascal analysis
Stascal analyses were performed using SPSS Ver-
sion 21.0 (IBM Corp, Armonk, NY, USA), with signi-
cance was set at P < 0.05. Data are expressed in mean
(standard deviaon). For the layup and jump shot land-
ings, analysis of variance (ANOVA) with repeated mea-
sures (Side × Court) was applied to the peak forces in
each of the eight foot regions. To correct for violaon
of sphericity, signicance was assessed from the Green-
house-Geisser correcon for epsilon values ≤ 0.75, and
the Huynh-Feldt correcon for epsilon > 0.75. Eect size
(paral eta squared, ηp
2) was calculated to describe the
magnitude of the dierence and values of 0.01, 0.09 and
at the free throw line using their preferred arm. All ex-
cept one parcipant shot with the right arm. Ten valid
trials were recorded using the same criteria as for the
layup described previously.
Sprint (Figure 1c). Maximal forward sprinng is highly
relevant to basketball since players sprint approximate-
ly every 39 s in a game [5]. Parcipants sprinted at max-
imal eort across the court, using the le foot as the
rst step. Since the sprint task was performed at max-
imal eort and hence more demanding than the other
tasks, ve instead of 10 successful trials were recorded
as done in a previous study on basketball-related move-
ments [8].
Aer compleng all tasks on one court surface
(wooden or asphalt), parcipants were asked to rate
their perceived level of discomfort at their ankles, knees,
and back using a visual analogue scale (VAS). The VAS
ranged from 0 (No discomfort) to 10 cm (Worst possible
discomfort) and was measured to the nearest 0.1 cm.
The same in-foot loading measurements and subjecve
percepon procedures were then repeated for the oth-
er court condion (wooden or asphalt).
Data processing
The double-leg landing steps of the layup and jump
shot were analyzed (Figure 1a and Figure 1b). Data of
the le and right feet were arranged into the shoong
and non-shoong side. The shoong side was dened as
Figure 1: Sequences of three typical basketball-related tasks: a) Layup; b) Jump shot; and c) Maximum forward sprint. Grey
circle indicates the step selected for analysis in each task.
• Page 4 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
eect size). During the sprint acceleraon step, higher
peak forces were observed on the wooden court com-
pared to asphalt court in two regions: hallux (P = 0.048,
medium eect size) and medial forefoot P = 0.010, large
eect size, Table 3).
Eight out of thirteen (61.5%) parcipants generally
preferred to play on wooden than arcial courts. Aer
performing the three basketball-related tasks on both
surfaces, no signicant dierences were found in the
VAS rangs at the ankle (wooden = 0.92 (1.11) cm, as-
phalt = 1.05 (0.99) cm, P = 0.635, r = -0.09), knee (wood-
en = 1.13 (1.68) cm, asphalt = 1.46 (1.64) cm, P = 0.293,
r = -0.21), and back (wooden = 0.89 (1.25) cm, asphalt =
0.94 (0.93) cm, P = 0.929, r = -0.02).
This study invesgated the inuence of court surface
(wood and asphalt) on foot loading during three basket-
ball-specic manoeuvres. Contrary to our hypothesis
that lower forces would be observed on wooden than
asphalt court, our ndings showed that wooden court
resulted in higher peak forces at the toes and medial
forefoot during layup landing and sprinng. These nd-
ings oppose the common beliefs by coaches, PE teach-
ers and athletes that wooden courts can provide beer
force aenuaon compared to asphalt courts.
Landing from jumps
Although a wooden court presents a soer landing
0.25 were interpreted as small, medium and large ef-
fects, respecvely [23]. Should a signicant Side × Court
interacon be found, post-hoc pairwise comparisons
with Bonferroni adjustment were applied.
For VAS rangs and sprint acceleraon peak forces,
Wilcoxon signed-rank test was used to compare be-
tween the wooden and asphalt courts data. Non-para-
metric test was chosen owing to the relavely small
sample size. Eect size (r) was calculated and interpret-
ed as follows: Small 0.1 ≤ |r| ≤ 29, medium 0.3 ≤ |r|
0.49, and large |r| ≥ 0.5 [24].
For the layup landing, elevated peak forces were
found on the wooden court than the asphalt court in
two-foot regions (Table 1): Hallux (P = 0.022, large ef-
fect size) and lesser toes (P = 0.007, large eect size).
There were a few bilateral dierences of large eect
sizes between the shoong and non-shoong sides. For
the only signicant Side × Court interacon observed in
the medial forefoot (P = 0.036, large eect size, Table
1), post-hoc analysis showed signicant side-to-side dif-
ference on the asphalt court but not the wooden court.
During jump shot landing, there was no main eect of
the court type or Side × Court interacon (Table 2). As
shown in Table 2, only signicant bilateral dierences
were found, with the non-shoong side displaying high-
er forces than the shoong side at the medial forefoot (P
= 0.039, large eect size) and the heel (P = 0.002, large
Figure 2: The eight-region mask for data extraction of in-shoe foot loading measurements.
• Page 5 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
likely to adopt slightly dierent landing techniques in re-
sponse to the landing surface [25]. The present study al-
lowed players to perform typical basketball tasks on real
courts, providing good ecological validity over mechan-
ical tests, simulaon studies, and controlled laboratory
experiments (e.g. drop landing on a force plaorm). Our
ndings are consistent with previous experimental stud-
ies in which higher peak vercal forces were associated
with landing onto a mat compared to a non-mat condi-
surface [3], the present study showed that force aen-
uaon was less eecve on the wooden than asphalt
court when landing from a layup. This is in contrast to
the results obtained from a simulaon study conduct-
ed by Kim, and colleagues [2], which demonstrated that
wood ground produced lower peak forces than asphalt.
It is believed that the simulaon study over-simplied
the human body as a rigid lower limb with no exion/
extension movement abilies. In reality, parcipants are
Table 1: Statistical results of peak forces (in body weight) in eight foot regions during layup landing.
Region Court Side Statistical Results
Side Court Interaction
Non-shooting Shooting P (ηp
2)P (ηp
2)P (ηp
Wood 0.15 (0.06) 0.09 (0.06)
< 0.001
Asphalt 0.15 (0.06) 0.08 (0.05)
Lesser toes
Wood 0.24 (0.09) 0.30 (0.09)
Asphalt 0.22 (0.09) 0.28 (0.08)
Wood 0.27 (0.06) 0.22 (0.07)
Asphalt 0.28 (0.05) 0.18 (0.07)
Wood 0.39 (0.07) 0.41 (0.08)
Asphalt 0.41 (0.08) 0.43 (0.10)
Wood 0.25 (0.08) 0.28 (0.08)
Asphalt 0.27 (0.10) 0.28 (0.08)
Medial arch
Wood 0.15 (0.11) 0.21 (0.12)
Asphalt 0.17 (0.09) 0.22 (0.11)
Wood 0.22 (0.11) 0.30 (0.12)
Asphalt 0.26 (0.09) 0.31 (0.11)
Wood 0.29 (0.24) 0.65 (0.35)
Asphalt 0.33 (0.19) 0.64 (0.27)
Wood 1.71 (0.31) 2.06 (0.51)
Asphalt 1.81 (0.26) 2.07 (0.63)
Note: Data are expressed in mean (SD). The shooting side was dened as the foot on the same side of the shooting arm (right
for all participants). Signicant P-values from repeated measures ANOVA (P < 0.05) are shown in bold. Effect size (ηp
2) values of
0.01, 0.09 and 0.25 were interpreted as small, medium and large effects, respectively.
• Page 6 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
Sprint acceleraon
It was found that when sprinng on the wooden
court, parcipants pushed o with greater force at the
hallux and medial forefoot compared to when moving
across the asphalt court. While it is possible that par-
cipants required more forces to push o from a more
compliant surface, the adopon of a dierent sprint
technique (increased planng at the forefoot) is likely
to be part of a compensatory mechanism to augment
on [25,26]. It is possible that parcipants in the pres-
ent study adopted a ser landing strategy owing to the
perceived higher compliance of the wooden compared
to asphalt surface. The higher force experienced when
landing on a more compliant surface is due to a ser
landing strategy characterized by reduced hip and knee
joint exion, coupled with increased acvaon of mus-
cles crossing the knee joint [25]. Future studies can con-
rm this speculaon by including kinemac variables.
Table 2: Statistical results of peak forces (in body weight) in eight foot regions during jump shot landing.
Region Court Side Statistical Results
Side Court Interaction
Non-shooting Shooting P (ηp
2)P (ηp
2)P (ηp
Wood 0.12 (0.06) 0.08 (0.04)
Asphalt 0.11 (0.07) 0.09 (0.05)
Lesser toes
Wood 0.21 (0.10) 0.22 (0.10)
Asphalt 0.18 (0.10) 0.21 (0.11)
Wood 0.25 (0.10) 0.18 (0.09)
Asphalt 0.24 (0.10) 0.20 (0.09)
Wood 0.40 (0.11) 0.34 (0.23)
Asphalt 0.36 (0.10) 0.32 (0.13)
Wood 0.23 (0.09) 0.20 (0.12)
Asphalt 0.20 (0.07) 0.21 (0.11)
Medial arch
Wood 0.07 (0.07) 0.05 (0.06)
Asphalt 0.07 (0.07) 0.08 (0.10)
Wood 0.16 (0.10) 0.10 (0.08)
Asphalt 0.15 (0.06) 0.13 (0.10)
Wood 0.38 (0.24) 0.23 (0.23)
(< 0.001)
Asphalt 0.35 (0.18) 0.22 (0.17)
Wood 1.30 (0.40) 1.09 (0.58)
Asphalt 1.23 (0.26) 1.20 (0.53)
Note: Data are expressed in mean (SD). The shooting side was dened as the foot on the same side of the shooting arm (right
n = 12, left n = 1). Signicant P-values from repeated measures ANOVA (P < 0.05) are shown in bold. Effect size (ηp
2) values of
0.01, 0.09 and 0.25 were interpreted as small, medium and large effects, respectively.
• Page 7 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
Potenal role of footwear
Both the layup and sprint are common movements
in basketball; the eect of increased peak forces experi-
enced while execung these manoeuvres on the wood-
en court is amplied due to the frequency at which they
are performed. Players, PE teachers and coaches should
be mindful of the loading demands across dierent
shoe-court combinaons, in parcular, the increased
forces associated with a more compliant and slippery
surface. Although the playing environment is usually un-
modiable, wearing appropriate footwear can play an
important role in aenuang forces. Most studies inves-
shoe-court fricon on the wooden court. Wooden sur-
faces have been found to possess fricon coecients
which are less than half of those of their asphalt coun-
terparts [27]. Thus, it was probable that parcipants
executed a sprinng technique which induced greater
tracon, in order to reduce the likelihood of slipping and
its resultant injury. However, it is also essenal to ac-
knowledge that excessive shoe-court fricon might give
rise to lower extremity injuries caused by overloading
[28]. Moreover, increased regional loading at the foot
could lead to higher skin temperature which could in
turn result in blistering [29].
Table 3: Statistical results of peak forces (in body weight) in eight foot regions during sprint acceleration step.
Region Surface Peak Force P-value Effect size (r)
Wood 0.13 (0.07)
0.048 -0.39
Asphalt 0.12 (0.07)
Lesser toes
Wood 0.34 (0.10)
0.140 -0.29
Asphalt 0.30 (0.06)
Medial forefoot
Wood 0.36 (0.12)
0.010 -0.50
Asphalt 0.34 (0.10)
Central forefoot
Wood 0.57 (0.12)
0.387 -0.17
Asphalt 0.56 (0.13)
Lateral forefoot
Wood 0.27 (0.10)
0.350 -0.18
Asphalt 0.25 (0.11)
Medial arch
Wood 0.04 (0.04)
0.573 -0.11
Asphalt 0.03 (0.04)
Lateral arch
Wood 0.10 (0.08)
0.289 -0.21
Asphalt 0.08 (0.07)
Wood 0.18 (0.26)
0.721 -0.07
Asphalt 0.14 (0.28)
Wood 1.62 (0.26)
0.011 -0.50
Asphalt 1.53 (0.28)
Note: Data are expressed in mean (SD). Signicant P-values from Wilcoxon signed-rank tests (P < 0.05) are shown in bold. Effect
sizes were interpreted as: small 0.1 ≤ |r| ≤ 29, medium 0.3 ≤ |r| ≤ 0.49, large |r| ≥ 0.5.
• Page 8 of 9 •
Kong et al. Int J Foot Ankle 2018, 2:009
tensive unilateral upper-limb usage had an imbalanced
strengthening eect on the lower-limbs, thereby result-
ing in asymmetrical landing strategies. As such, players
and coaches should be aware of the loading asymmetry
when landing from these movements and implement
appropriate intervenons such as using customised or-
thoses. Future research should consider examining the
eect of upper-limb dominance on lower-limb biome-
chanics during basketball tasks.
There were a few limitaons to this study. Firstly,
no kinemac or performance variables such as jump
height and sprint speed were obtained. Such informa-
on would have been useful in understanding the re-
laonship between surface compliance and movement
technique adopted by the parcipants. Considering that
the parcipants in the present study were skilled play-
ers and that the movement tasks studied were basic and
frequently executed skills [5,17,20,21], it is unlikely that
they would alter their performance substanally due to
surface compliance. Moving forward, kinemac analy-
sis should be included in addion to foot loading such
that jump height and landing techniques between sur-
faces can be compared. Secondly, mechanical tests to
accurately measure surface compliance and shoe-sur-
face tracon were not conducted due to the constraints
in facilies and resources in our laboratory. Since the
wooden and asphalt surfaces used in the present study
are standard sport courts, it is expected that their re-
specve mechanical properes are similar to those re-
ported in the literature. To strengthen the study design,
future studies should include mechanical tests to meas-
ure the sness of dierent court surfaces. Thirdly, only
peak forces at the foot were measured and these forces
do not necessarily reect the loading at individual joints
such as the knee and the hip. Inverse dynamics calcu-
laons would be needed to quanfy joint kinecs for a
more comprehensive analysis. Finally, it should be ac-
knowledged the P-values reported throughout are un-
adjusted nominal values. Since the peak force in several
foot regions were stascally compared, readers should
be aware of the increased change of comming type I
error resulng from mulple comparisons.
As opposed to common percepon and previous
simulaon study ndings, the present experimental
study on basketball players showed that wooden courts
did not provide beer impact force aenuaon com-
pared to asphalt courts. Instead, players experienced
greater peak forces at the toes and medial forefoot on
the more compliant wooden court during layup landing
and sprinng. Coaches, PE teachers and athletes should
be informed that playing basketball on wooden courts
can expose players to higher forces in the foot. Future
studies should invesgate the interplay between playing
surface, foot loading, and risk of injuries.
gang the interacon between athlec shoe and play-
ing surface have focused on the property of shoe-sur-
face tracon [30,31]. The ndings of this study suggest
that shoe-surface interacon can also aect vercal im-
pact loading alongside shearing forces. Thus, shoe cush-
ioning properes such as midsole hardness should be
invesgated along with friconal properes to provide
a beer understanding of the shoe-surface interacon.
This is especially imperave for sports such as basket-
ball which frequently involves both jumping and running
movements. Future work could look at how both the
friconal and cushioning properes of a shoe inuence
contact forces at foot-shoe and shoe-surface interfaces.
Perceptual response to playing surfaces
In addion to biomechanical loadings, perceptual
responses of the parcipants to landing on the dier-
ent surfaces were also studied. It was found that parc-
ipants perceived landing on both surfaces to be equally
comfortable. A previous study showed that basketball
players are able to disnguish between shoe midsole
hardness condions through the perceptual parame-
ter of comfort level while performing several basketball
movements [10]. In another study on layup and side-cut-
ng tasks, recreaonal basketball players indicated sim-
ilar perceived stability for shoes with soer and harder
midsoles, and that there was no relaonship between
biomechanical and subjecve measurements [32]. In
the present study, the majority of parcipants preferred
playing on a wooden to an asphalt court. There were,
however, no dierences in perceptual responses to
comfort at the ankle, knee, and back aer performing
basketball-related movements on both courts. This sug-
gests that players might be more sensive to changes
in shoe hardness [10,19] compared to surface compli-
ance. It is also likely that a certain threshold of impact
force may be required for neural feedback of the body
before an individual can accurately dierenate be-
tween shoe-surface compliance condions. Given that
players’ court preference can be inuenced by factors
other than comfort, future studies should consider in-
vesgang the relaonship between perceived surface
compliance and landing biomechanics.
Bilateral asymmetry
The layup and jump shot are movements involving
a double-leg landing; the bilateral asymmetry of such
landings has been found to be associated with low-
er-limb injuries [33]. An interesng secondary nding
in the present study showed that when landing from a
layup, side-to-side asymmetry of impact forces exists,
with substanal asymmetry directed towards the shoot-
ing side at the lateral arch and heel regions. This bilat-
eral asymmetry might have developed from prolonged
parcipaon in a sport which relies predominantly on
unilateral upper-limb movements, for example, drib-
bling and shoong in basketball. It is possible that in the
kinec chain of dierent basketball movements, an ex-
• Page 9 of 9 •
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The authors declare that they have no compeng in-
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... Mixed results have also been found for landings on different surfaces. A comparison of wood and asphalt court surfaces found lower forces at the hallux and lesser toes during lay-up landings on the asphalt surface, but no difference was observed during jump shot landings (Kong, Nin, Quek, & Chua, 2018). Greater VILR has been observed on sport court surfaces with lower energy absorption during consecutive countermovement jumps when participants were shod in a minimalist shoe, but not in a conventional shoe (Malisoux et al., 2017). ...
... A wide variety of surface and shoe constructions are available and their effects on impact parameters may be specific to the type of shoe or surface, or the range of the parameter (e.g., stiffness) that was modified. Studies investigating the influence of surface on landing impact have used foam over concrete (Gross & Nelson, 1988;Lafortune et al., 1996), sport flooring (Malisoux et al., 2017), wood, and asphalt surfaces (Kong et al., 2018). Wooden court surfaces are standard at the collegiate and professional level for many sports including basketball (International Basketball Federation, 2009). ...
... The lack of surface effects on vGRF, VILR, and acceleration measures adds support to previous studies which observed no influence of surface on impact measures (Gross & Nelson, 1988;Malisoux et al., 2017). Studies which found differences in plantar pressure and VILR between surface conditions investigated different measures, plantar pressure under specific regions of the foot (Kong et al., 2018), or only observed differences when participants performed a different jumping task (hopping) or were shod in a minimalist shoe (Malisoux et al., 2017). ...
Full-text available
Foot-ground contact upon landing from a jump results in an impulsive impact force. Parameters of impact including vertical ground reaction force (vGRF), loading rate, tibial acceleration, and impact attenuation have been associated with lower limb injury risk. Differences in shoe stiffness and surface construction may influence impact loading and attenuation, but evidence is limited. The purpose of this study was to quantify the influence of basketball court surface construction and shoe midsole stiffness on ground reaction force, joint work, and acceleration measures during countermovement jump landings. Twenty-nine male collegiate and high school basketball players performed maximal countermovement jumps in each of three basketball shoes and on three wood court surfaces with varying compressive stiffness. Peak vGRF, vertical instantaneous loading rate, tibial and head acceleration, impact attenuation, and joint work at the ankle and knee were quantified. No differences in peak vGRF, loading rate, impact attenuation, or knee joint work were observed between surface or shoe conditions (p ≥ 0.056). Eccentric ankle work was lowest on the stiffest surface (p ≤ 0.014). Peak resultant tibial acceleration in the time domain and axial tibial high frequency signal power magnitude in the frequency domain were lowest in the most compliant shoe (p = 0.005 and p = 0.046, respectively). The few significant findings for shoe stiffness and the somewhat counterintuitive finding for surface suggest that shoe and surface stiffness have minimal effects on parameters associated with impact during countermovement jump landings.
... Another study [95] evaluated the extent to which foot loading is affected by the court surface (wood or asphalt) on which basketball is played. For this purpose, three tasks related to basketball were performed, both on wood and asphalt courts, by the study participants: layup, jump shot, and maximal effort sprint. ...
... The application of Pedar-X for basketball players [95] might evolve mainly three new directions: obtaining also kinematic data, such as sprint speed or jump height; evaluation of the stiffness for various court surfaces (besides wood and asphalt, used in the study); taking into account not only the plantar forces, but also the joint kinetics. ...
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The present paper reviews, for the first time, to the best of our knowledge, the most recent advances in research concerning two popular devices used for foot motion analysis and health monitoring: smart socks and in-shoe systems. The first one is representative of textile-based systems, whereas the second one is one of the most used pressure sensitive insole (PSI) systems that is used as an alternative to smart socks. The proposed methods are reviewed for smart sock use in special medical applications, for gait and foot pressure analysis. The Pedar system is also shown, together with studies of validation and repeatability for Pedar and other in-shoe systems. Then, the applications of Pedar are presented, mainly in medicine and sports. Our purpose was to offer the researchers in this field a useful means to overview and select relevant information. Moreover, our review can be a starting point for new, relevant research towards improving the design and functionality of the systems, as well as extending the research towards other areas of applications using sensors in smart textiles and in-shoe systems.
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RESUMO O basquete é um esporte dinâmico que possui características intermitentes durante a realização das suas diversas tarefas motoras. A natureza das ações motoras executadas pelos jogadores acabam exigindo em variados graus da força e potência musculares. Isto pode ser observado nos movimentos multiplanares acelerativos, desacelerativos, mudanças bruscas de direção, saltos, aterrisagens, entre outras situações técnico-táticas que envolvem o ataque ou a defesa nas partidas. Treinar a força motora é uma condição básica elementar para o aprimoramento de outras capacidades biomotoras. Entre os recursos pedagógicos para o desenvolvimento da força, temos o uso da metodologia funcional. Sendo assim, neste manuscrito discutimos alguns aspectos relacionados ao treinamento da força funcional direcionada especificamente aos basquetebolistas. Palavras-chave: Basquete, Treinamento da Força, Treinamento Funcional, Treinamento Esportivo, Basketball, Sports Training, Strength Training, Functional Training
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This study investigated the between-limb asymmetry in kinetic and temporal characteristics during bilateral plyometric drop jumps from different heights. Seventeen male basketball players performed drop jumps from 3 heights on two platforms in randomized orders. Vertical ground reaction force data were analyzed with respect to the lead limb (i.e. the limb stepping off the raised platform first) and trail limb. Peak forces and loading rates of each limb were calculated. The absolute time differential between the two limbs at initial ground contact and takeoff were determined. The frequency of symmetrical landing and taking off with ‘both limbs together’ were counted using 3 time windows. Results showed that the lead limb displayed higher peak forces and loading rates than the trail limb across all heights (p < .05). As drop height increased, the absolute time differentials decreased at initial ground contact (p < .001) but increased at takeoff (p = .035). The greater the preset time window, the more landings and takeoffs were classified as bilaterally symmetrical. In conclusion, higher drop heights allowed subjects to become more bilaterally symmetrical in the timing of landing but this reduction in temporal asymmetry did not accompany with any reduction in kinetic asymmetry.
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يسعى الباحث من خلال هذا العمل إلى عرض وتحليل للعديد من الأبحاث العلمية الدولية والتي ركزت إهتماماتها على مجالات العلوم المرتبطة بكرة السلة مثل التدريب الرياضي، والميكانيكا الحيوية، وفسيولوجيا الرياضة، حيث يطمح الباحث من خلال هذا العرض إلى التوصل إلى أهم الاستخلاصات التي من شأنها رسم إستراتيجيات حقيقية واقعية في مجال تدريب كرة السلة، وذلك من خلال عدة محاور هامة
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BACKGROUND: Biomechanical analysis of the foot loading characteristics may provide insights into the injury mechanisms and guide orthotic prescription for basketball players. This study aimed to quantify the in-shoe plantar pressure profiles in amateur players when executing typical basketball movements. METHODS: Twenty male university basketball players performed four basketball-specific movement tasks: running, maximal forward sprinting, maximal 45° cutting, and lay-up in a pair of standardized basketball shoes fitted with an in-shoe plantar pressure measurement system. Peak pressure (PP) and pressure time integral (PTI) were extracted from 10 plantar regions. One-way repeated measures ANOVA was performed across the tasks, with the significance set at .05. RESULTS: Distinct plantar pressure distribution patterns were observed among the four movements. As compared to running, significantly higher (p < .05) PP and PTI of up to ~55% were found in sprinting and lay-up particularly at the forefoot region. Similarly, significantly higher (p < .05) PP and PTI ranging from ~23 to 90% were observed in 45° cutting compared to running at most foot regions. CONCLUSIONS: Compared to running, sprinting and lay-up demonstrated higher plantar loading in the forefoot region while 45° cutting yielded increased plantar loading in most regions of the foot. Understanding the plantar pressure characteristics of different movements may be useful in optimizing footwear designs, orthoses use, or training strategies to minimize regional plantar loading during amateur basketball play.
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This study aimed to investigate the effects of varying midsole hardness on center of pressure (COP) and perceived stability during basketball-specific tasks, as well as the correlation between COP and perception measurements. Twenty male basketball players performed 45° cutting and lay-up while wearing basketball shoes with soft and hard midsoles. COP trajectories were obtained from the Pedar insole system. Stability perceptions at the forefoot and rearfoot were assessed using 150-mm visual analogue scales (VAS). Results indicated greater COP mediolateral deviations in soft midsole compared with hard midsole during lay-up (soft 16.6 ± 4.7 mm, hard 15.8 ± 4.6 mm, p = .025) but not 45° cutting (soft 15.7 ± 5.9 mm, hard 15.8 ± 5.6 mm, p = .601). While 16 out of 20 participants preferred soft midsole, no significant difference in VAS ratings was found between shoes for both tested movements. There was no significant correlation between COP and perceived stability during lay-up or 45° cutting. In conclusion, midsole hardness of basketball shoes did not consistently affect mediolateral stability of the foot during 45° cutting and lay-up. Subjective perception alone cannot be used to indicate mediolateral deviation of the foot when executing basketball-specific maneuvers.
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This study examined how shoe midsole hardness influenced plantar pressure in basketball-related movements. Twenty male university basketball players wore customized shoes with hard and soft midsoles (60 and 50 Shore C) to perform four movements: running, maximal forward sprinting, maximal 45° cutting and lay-up. Plantar loading was recorded using an in-shoe pressure measuring system, with peak pressure (PP) and pressure time integral (PTI) extracted from 10 plantar regions. Compared with hard shoes, subjects exhibited lower PP in one or more plantar regions when wearing the soft shoes across all tested movements (Ps < 0.05). Lower PTI was also observed in the hallux for 45° cutting, and the toes and forefoot regions during the first step of lay-up in the soft shoe condition (Ps < 0.05). In conclusion, using a softer midsole in the forefoot region may be a plausible remedy to reduce the high plantar loading experienced by basketball players.
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This study aimed (1) to profile the plantar loading characteristics when performing the basketball lay-up in a realistic setting and (2) to determine the number of trials necessary to establish a stable mean for plantar loading variables during the lay-up. Thirteen university male basketball players [age: 23.0 (1.4) years, height: 1.75 (0.05) m, mass: 68.4 (8.6) kg] performed ten successful basketball lay-ups from a stationary position. Plantar loading variables were recorded using the Novel Pedar-X in-shoe system. Loading variables including peak force, peak pressure, and pressure-time integral were extracted from eight foot regions. Performance stability of plantar loading variables during the take-off and landing steps were assessed using the sequential averaging technique and intra-class correlation coefficient (ICC). High plantar loadings were experienced at the heel during the take-off steps, and both the heel and forefoot regions upon landing. The sequential estimation technique revealed a five-eight trial range to achieve a stable mean across all plantar loading variables, whereas ICC analysis was insensitive to inter-trial differences of repeated lay-up performances. Future studies and performance evaluation protocols on plantar loading during basketball lay-ups should include at least eight trials to ensure that the measurements obtained are sufficiently stable.
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This study investigated the effects of body mass and shoe midsole hardness on kinetic and perceptual variables during the performance of three basketball movements: (1) the first and landing steps of layup, (2) shot-blocking landing and (3) drop landing. Thirty male basketball players, assigned into "heavy" (n = 15, mass 82.7 ± 4.3 kg) or "light" (n = 15, mass 63.1 ± 2.8 kg) groups, performed five trials of each movement in three identical shoes of varying midsole hardness (soft, medium, hard). Vertical ground reaction force (VGRF) during landing was sampled using multiple wooden-top force plates. Perceptual responses on five variables (forefoot cushioning, rearfoot cushioning, forefoot stability, rearfoot stability and overall comfort) were rated after each movement condition using a 150-mm Visual Analogue Scale (VAS). A mixed factorial analysis of variance (ANOVA) (Body Mass × Shoe) was applied to all kinetic and perceptual variables. During the first step of the layup, the loading rate associated with rearfoot contact was 40.7% higher in the "heavy" than "light" groups (P = .014) and 12.4% higher in hard compared with soft shoes (P = .011). Forefoot peak VGRF in a soft shoe was higher (P = .011) than in a hard shoe during shot-block landing. Both "heavy" and "light" groups preferred softer to harder shoes. Overall, body mass had little effect on kinetic or perceptual variables.
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The ability to shoot an effective jump shot in the sport of basketball is critical to a player’s success. In an attempt to better understand the aspects related to expert performance, researchers have investigated successful free throws and jump shots of various basketball players and identified movement variables that contribute to their success. The purpose of this study was to complete a systematic review of the scientific literature on the basketball free throw and jump shot for the purpose of revealing the critical components of shooting that coaches, teachers, and players should focus on when teaching, learning, practising, and performing a jump shot. The results of this review are presented in three sections: (a) variables that affect ball trajectory, (b) phases of the jump shot, and (c) additional variables that influence shooting.
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This paper presents some of the methodology, observations and findings from a 30-month study, aiming to improve the understanding of tennis shoe-court interactions and the biomechanical implications of changes in friction between the shoe and surface. A detailed programme of biomechanical player testing on different court surfaces provided the boundary conditions with which to develop a lab-based rig capable of simulating the key aspects of shoe-surface interaction that are required for acceptable performance (e.g. push-off to accelerate) within expected levels of consistency (e.g. for a controlled slide). Large- scale parametric testing could then be carried out for a variety of surface types and components under a range of loading conditions, without the risk of injury to human participants. Two case studies are described to demonstrate the value of a combined approach of biomechanical field testing and lab-based rigs that simulate shoe-court interactions. These include a study that compared different artificial clay court designs; and a study that examined the effect of different acrylic hard court parameters on friction and the tribological mechanisms that explain the observed interaction
Basketball is a sport that involves multiple impacts with the ground through a variety of moves such as running Jumping, and cutting. Repetitive impacts have been associated with stress-related injuries in other sports such as running. The purpose of this investigation was to gain an understanding of the typical stresses the body experiences during common basketball moves. To this end, the ground reaction forces from 24 players from five professional basketball teams were studied. In addition, a game analysis was performed to determine the frequency of selected moves. These data indicated that certain common movements, such as jump landings and shuffling, resulted in absolute and relative forces much greater than many of those reported previously in studies of other sports. These movements were also identified in a companion paper as being associated with large angular excursions and velocities. Findings are discussed with respect to injury risks, and suggestions for future study are made.
This paper investigates the effects of sports ground materials on the transfer characteristics of the landing impact force using a coupled foot-shoe-ground interaction model. The impact force resulting from the collision between the sports shoe and the ground is partially dissipated, but the remaining portion transfers to the human body via the lower extremity. However, since the landing impact force is strongly influenced by the sports ground material we consider four different sports grounds, asphalt, urethane, clay and wood. We use a fully coupled 3-D foot-shoe-ground interaction model and we construct the multi-layered composite ground models. Through the numerical simulation, the landing impact characteristics such as the ground reaction force (GRF), the acceleration transfer and the frequency response characteristics are investigated for four different sports grounds. It was found that the risk of injury, associated with the landing impact, was reduced as the ground material changes from asphalt to wood, from the fact that both the peak vertical acceleration and the central frequency monotonically decrease from asphalt to wood. As well, it was found that most of the impact acceleration and frequency was dissipated at the heel, then not much changed from the ankle to the knee.