sports
Review

How Can Biomechanics Improve Physical Preparation and
Performance in Paralympic Athletes? A Narrative Review
Jared R. Fletcher 1, * , Tessa Gallinger 2 and Francois Prince 3,4
1
2
3

4

*







Citation: Fletcher, J.R.; Gallinger, T.;
Prince, F. How Can Biomechanics
Improve Physical Preparation and
Performance in Paralympic Athletes?
A Narrative Review. Sports 2021, 9, 89.
https://doi.org/10.3390/
sports9070089
Academic Editor: Luca Paolo Ardigo

Department of Health and Physical Education, Mount Royal University, Calgary, AB T3E 6K6, Canada
Canadian Sport Institute Calgary, Calgary, AB T3B 6B7, Canada; tgallinger@csicalgary.ca
Department of Surgery, Faculty of Medicine, University of Montreal, Montreal, QC H3T 1J4, Canada;
francois.prince@umontreal.ca
Institut National du Sport du Québec, Montréal, QC H1V 3N7, Canada
Correspondence: jfletcher@mtroyal.ca

Abstract: Recent research in Paralympic biomechanics has offered opportunities for coaches, athletes,
and sports practitioners to optimize training and performance, and recent systematic reviews have
served to summarize the state of the evidence connecting biomechanics to Paralympic performance.
This narrative review serves to provide a comprehensive and critical evaluation of the evidence
related to biomechanics and Paralympic performance published since 2016. The main themes within
this review focus on sport-specific body posture: the standing, sitting, and horizontal positions of
current summer Paralympic sports. For standing sports, sprint and jump mechanics were assessed
in athletes with cerebral palsy and in lower-limb amputee athletes using running-specific prostheses. Our findings suggest that running and jumping-specific prostheses should be ‘tuned’ to each
athlete depending on specific event demands to optimize performance. Standing sports were also
inclusive to athletes with visual impairments. Sitting sports comprise of athletes performing on a
bike, in a wheelchair (WC), or in a boat. WC configuration is deemed an important consideration
for injury prevention, mobility, and performance. Other sitting sports like hand-cycling, rowing, and
canoeing/kayaking should focus on specific sitting positions (e.g., arm-crank position, grip, or seat
configuration) and ways to reduce aero/hydrodynamic drag. Para-swimming practitioners should
consider athlete-specific impairments, including asymmetrical anthropometrics, on the swim-start and
free-swim velocities, with special considerations for drag factors. Taken together, we provide practitioners working in Paralympic sport with specific considerations on disability and event-specific training
modalities and equipment configurations to optimize performance from a biomechanical perspective.
Keywords: kinematics; prostheses; classification; amputee; cerebral palsy

Received: 5 May 2021
Accepted: 18 June 2021
Published: 24 June 2021

Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affiliations.

Copyright: © 2021 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
conditions of the Creative Commons
Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).

1. Introduction
In 2016, 176 countries and more than 4000 athletes competed at the Paralympic Games.
These athletes remain significantly understudied compared to Olympic athletes, especially
with regards to the role the field of biomechanics can serve in improving physical preparation and performance. Recently, Morriën et al. [1] conducted a systematic review of
biomechanical studies in Paralympic research consisting of 41 articles published before July
2016, showing that the majority of the included studies contribute to our understanding
of technical optimization, injury prevention, and evidence-based classification. Because
of the nature of the systematic review itself, a critical analysis of the 41 biomechanical
studies was not included. Here, we serve to update this review and to examine the impact that specific biomechanical interventions may have on Paralympic performance. We
construct this narrative review by considering Paralympic athletes and their specific impairment(s) and their sport’s specific body posture: standing, sitting, and horizontal positions
(Table 1). We summarize the newest biomechanical evidence related to these athletes and
their physical preparation, performance, and potential use of technological innovation. We
then offer practical suggestions for coaches, Paralympic athletes, and sports practitioners
to optimize Paralympic athlete performance.

Sports 2021, 9, 89. https://doi.org/10.3390/sports9070089

https://www.mdpi.com/journal/sports

Sports 2021, 9, 89

2 of 15

Table 1. 2020(1) Paralympic sports, sport-specific body posture, and impairment(s).
SPORT

Archery
Athletics
Badminton
Boccia
Canoe Sprint
Cycling
Equestrian
Football
5-a-side
Goalball
Judo
Powerlifting
Rowing
Shooting
Swimming
Table Tennis
Taekwondo
Triathlon
Wheelchair
Basketball
Wheelchair
Fencing
Wheelchair
Rugby
Wheelchair
Tennis

POSTURE

STANDING
SITTING
STANDING
SITTING
STANDING
SITTING
SITTING
SITTING
SITTING
SITTING

IMPAIRED

IMPAIRED

MUSCLE
POWER
x

PASSIVE
ROM
x

LIMB

LEG LENGTH

INTELLECTUAL

INVOLUNTARY

MUSCLE

UNCOORDONATED

SHORT

VISION

DEFICIENCY

DIFFERENCE

IMPAIRMENT

MOVEMENTS

TENSION

MOVEMENTS

STATURE

IMPAIRMENT

x

x

x

x

x

x

x

x

x

x

x
x
x
x
x

x
x
x
x
x

x
x
x
x
x

x

x
x

x
x

x
x

x

x
x

x
x

x
x

x
x

x
x

x

x

x

x
x

STANDING

x

STANDING
STANDING
SUPINE
SITTING
STANDING
SITTING
SUPINE
STANDING
SITTING
STANDING
STANDING
SITTING

x
x
x
x
x

x
x
x

x
x
x

x

x
x

x
x

x
x

x
x

x
x

x

x

x

x

x

x

SITTING

x

x

x

SITTING

x

x

SITTING

x

SITTING

x

x

x
x
x

x
x
x

x
x
x

x

x
x

x
x

x
x

x
x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x
x
x

x

Sports 2021, 9, 89

3 of 15

2. Standing
Standing postures are part of many Paralympic events (Table 1). We focus our narrative
on the main themes of biomechanics research published since 2016: sprinting and jumping
with prostheses, sprinters with cerebral palsy, and considerations for athletes with a visual
impairment. We recognize that other standing postures may be omitted here given the lack
of biomechanics-related research published since 2016.
2.1. Sprinting Biomechanics: The Basics
Running speed is the product of step length and step frequency. These changes in
kinematics are produced as the result of changes in kinetic quantities. Step length increases
by applying greater horizontal and vertical ground reaction forces during ground contact,
which increases a runner’s horizontal and vertical takeoff velocities and thus increases the
aerial time and the horizontal distance covered by the runner’s centre of mass [2,3]. Step
frequency increases are achieved by reducing foot–ground contact time and/or the time
taken to reposition the swinging limb for the next step.
2.2. Amputee Mechanics
Unilateral and bilateral lower limb amputee runners use running-specific prostheses
made of carbon-fibre sockets and blades attached in-series with the residual limb(s). The
blade works as a leaf spring to store and release elastic energy during running [4], returning
up to 95% of the mechanical energy stored in them [5]. Unlike running-specific prostheses,
lower limbs ‘return’ greater than 100% mechanical energy since active muscle contraction
contributes to positive joint work [6]; thus, compared to an intact lower limb, runningspecific prostheses are disadvantaged with regard to energy storage and return. The storage
and return of the mechanical work in intact human limbs require metabolic energy through
active muscle contraction [7], which is not the case with running-specific prostheses.
Running-specific prostheses also do not allow any neural adjustments (from active muscle
contraction) in stiffness during running. Thus, stark differences in lower limb kinematics
between able-bodied and lower-limb amputee runners have been reported [8–13]. Runningspecific prostheses are also available in different models with different geometries [14]
and mechanical properties [5], and they can be modified for running-specific prostheticsocket alignment and prosthetic height [15], the latter of which is to respect the maximum
allowable standing height as regulated by the International Paralympic Committee.
The running kinematics and kinetics of elite Paralympians using running-specific
prostheses and whether these devices incur an advantage to the Paralympians has been
contentious [16,17]. Unilateral transtibial lower-limb amputees achieve top speeds by
eliciting different spatiotemporal and vertical GRF characteristics compared to bilateral
lower-limb amputees or able-bodied sprinters [9]. Specifically, sprinting with runningspecific prostheses results in longer step lengths compared to a biological limb as well as
lower and longer vertical GRF compared to the sound leg [9,10]. Thus, similar vertical
impulses can be produced with lower peak vertical GRF forces with running-specific
prostheses; the total resultant force application does not need to be as high nor the lower
limb strength as great in sprinters using running-specific prostheses.
Running-specific prosthetic height and stiffness, the latter of which is influenced by
running speed, can be modified. Taboga et al. [15] found, however, no effect of height or
stiffness on maximum sprint speed (over a relatively narrow range of stiffnesses (±1 stiffness category) or heights (±2 cm)). This does not imply that changes in stiffness and/or
height beyond those that were tested would not infer a performance advantage. Indeed, a
recent ruling by the Court of Arbitration for Sport ruled a Paralympic Champion ineligible
to compete at the Olympics largely as a result of his running-specific prosthetic height [18].
Running-specific prosthetic alignment in the sagittal plane relative to the intact limb
has only recently been investigated. Migliore et al. [19] examined the impact of increasing
the sagittal tilt from 5◦ to 12◦ relative to the line of gravity in a gold medal Paralympian.
With this change in alignment, the athlete was able to increase step frequency and reduce

Sports 2021, 9, 89

4 of 15

step length with the sound side. With a higher sagittal tilt, the propulsive impulse was
higher, and the braking impulse decreased. Importantly, the athlete perceived the increased
tilt as the best running-specific prosthetic alignment, and shortly after implementing the
tilt alignment, she improved upon her personal best in the T42 100 m, narrowly missing
the world record.
Importantly, athletes looking to change their running-specific prosthetic model, alignment, and/or height must be aware that these changes likely alter the stiffness profile of
the running-specific prosthetic [5]. Specifically, the running-specific prosthetic stiffness
increases with the magnitude of the peak resultant GRF but decreases when the angle
between the running-specific prosthetic and resultant GRF is increased. This inverse relationship between GRFs and angle may explain previous reports that running-specific
prosthetic stiffness does not change during running [10,11].
The maximum resultant force an athlete can produce limits the maximal sprint speed
around a curve [2,20]. Running around a curve requires athletes to apply an additional
centripetal force to change direction in addition to the horizontal and vertical propulsive
forces. In sprint events of 200 m and 400 m, an athlete must negotiate either one or
two curves, respectively, with the inside leg relative to the curve always being the left
leg (since all races are run in the counterclockwise direction). This may disadvantage
left legged single lower-limb amputee sprinters since both the compliance and passive
nature of running-specific prostheses reduce the application of the maximal forces on the
ground [10]. Indeed, lower-limb amputee sprinters were 4% slower with the affected leg
on the inside of the curve compared to sprinting with the affected leg on the outside of the
curve due to their inability to generate large forces with their affected leg [21]. Single-leg
strength and speed training may be required in order to improve the affected limb’s ability
to generate large vertical and centripetal forces during sprint running, and/or athletes
should consider a better prosthetic design to help improve curve running in single and
double-leg amputee sprinters.
2.3. Mechanics of Sprinters with Cerebral Palsy
Cerebral palsy is associated with a series of permanent movement disorders resulting
from an upper motor neuron lesion in the brain. This impairment is not progressive
in nature, but it likely causes secondary adaptations to the muscle structure, function,
and composition [22]. Athletes with cerebral palsy will experience muscle weakness [23],
increased antagonist coactivation [24], spasticity [25], reduced muscle and joint power, and
limited range of motion [26].
Sprinters with cerebral palsy show lower force production compared to their ablebodied counterparts, which is likely a result of the reduced lower-limb strength in cerebral
palsy. For example, over a 10 m sprint, a Paralympic sprint medalist with cerebral palsy
(T36) showed lower average horizontal power compared to able-bodied sprinters, attributable to both higher horizontal braking and lower propulsive forces resulting in a
lower net propulsive impulse [27]. The larger horizontal braking forces in the athlete with
cerebral palsy, along with a stiffer ankle joint, were attributed to the increased muscle
co-contractions commonly observed in cerebral palsy [28–30]. Increased passive and active
(from antagonist co-activation) joint stiffness contribute to the reduced joint angular velocities, external joint power, and reductions in step length during the initial acceleration
phase of sprinting.
In summary, training interventions should focus on strategies to increase lower limb
joint angular velocities and positive joint powers. Increases in the strength and power
of the muscles that cross the hip and knee extensors is recommended to improve sprint
performance, primarily because the powerful hip joint performs negative work in cerebral
palsy yet performs net positive work in able-bodied athletes [27].

Sports 2021, 9, x FOR PEER REVIEW

Sports 2021, 9, 89

7 of 18

the muscles that cross the hip and knee extensors is recommended to improve sprint5 perof 15
formance, primarily because the powerful hip joint performs negative work in cerebral
palsy yet performs net positive work in able-bodied athletes [27].
2.4. Biomechanics
Biomechanics of
of Jumping
Jumping
2.4.
The performance
performance gap
gap between
between the
the Olympic
Olympic and
and unilateral
unilateral lower-limb
lower-limb amputee
amputee ParParThe
alympic winning
winning jumps
jumps is
is reducing
reducing (Figure 1). In the past, Paralympic champions have
alympic
been permitted
permitted to
to compete
compete at
at the
the Olympics
Olympics on
on the
the track
track [13], and it may soon be the case
been
that
Paralympic
long
jumpers
will
compete
at
the
Olympics
as well.
well.
that Paralympic long jumpers will compete at the Olympics as

Figure 1.
1. Men′s
Men’sgold
goldmedal
medalwinning
winninglong
longjumps
jumps for
forthe
theOlympics
Olympics and
and Paralympic
Paralympic Games
Games from
from 1992
Figure
to
to 2016.
2016. Olympic-winning
Olympic-winning jumps
jumps are
are shown
shown in filled circles. Paralympic-winning
Paralympic-winning F44
F44 jumps
jumps are
shown
shown in
in open
open circles.
circles. Filled
Filled bars
bars indicate
indicate the
the percent
percent difference
difference between
between Olympic
Olympic and
and Paralympic
Paralympic
winning
jumps.
winning jumps.

Biomechanically,
thethe
horizontal
distance
of
Biomechanically, the
the goal
goalof
ofthe
thelong
longjump
jumpisistotomaximize
maximize
horizontal
distance
the
jump.
This
is
accomplished
by
generating
as
much
vertical
velocity
at
take-off
while
of the jump. This is accomplished by generating as much vertical velocity at take-off
minimizing
the lossthe
in horizontal
velocity velocity
gained on
the approach
run-up. To
do so, Olymwhile minimizing
loss in horizontal
gained
on the approach
run-up.
To do
pic
and unilateral
lower-limb
amputeeamputee
long jumpers
lower their
centre
massofonmass
the
so, Olympic
and unilateral
lower-limb
long jumpers
lower
theirofcentre
approach
to the board
generate
as muchas
vertical
thus(and
vertical
on the approach
to thetoboard
to generate
much impulse
vertical (and
impulse
thusvelocity)
vertical
during
take-off
possible.
Compared
to non-amputee
jumpers,jumpers,
elite unilateral
lowervelocity)
duringas
take-off
as possible.
Compared
to non-amputee
elite unilateral
lower-limb
amputees
approach
theslower
board but
slower
but achieve
similar vertical
velocities
limb
amputees
approach
the board
achieve
similar vertical
velocities
at takeat take-off
[31].
The horizontal
slower horizontal
wouldaimply
a disadvantage
to unilateral
off
[31]. The
slower
velocityvelocity
would imply
disadvantage
to unilateral
lowerlower-limb
amputees
compared
to Olympic
jumpers
as a result
ofrunning-specific
their running-specific
limb
amputees
compared
to Olympic
jumpers
as a result
of their
prosprostheses.
However,
energy
is stored
portion
whichisisreturned)
returned)in
in running-specific
running-specific
theses.
However,
energy
is stored
(a (a
portion
ofof
which
prostheses that
that may
may exceed
exceed that
that of a biological limb. In
In support,
support, Funken
Funken et
et al. [32] have
prostheses
shown that
amputees
have
a longer
compression
phase phase
and a greater
shown
that unilateral
unilaterallower-limb
lower-limb
amputees
have
a longer
compression
and a
downward
motion motion
of the centre
mass,ofwhich
effective
in generating
vertical
greater
downward
of theofcentre
mass,would
whichbe
would
be effective
in generating
impulseimpulse
and storing
and returning
energyenergy
withinwithin
the running-specific
prostheses.
An
vertical
and storing
and returning
the running-specific
prostheses.
optimal
running-specific
prosthetic
stiffness,
one
that
maximizes
the
storage
and
return
of
An optimal running-specific prosthetic stiffness, one that maximizes the storage and reenergy
while also
maximizing
the pivot
that
translates
a portion
of the horizontal
velocity
turn
of energy
while
also maximizing
the
pivot
that translates
a portion
of the horizontal
to vertical
velocityvelocity
at take-off
[31] should
be investigated.
This optimal
stiffness
may
velocity
to vertical
at take-off
[31] should
be investigated.
This optimal
stiffness
be
different
than
the
optimal
running-specific
prosthetic
stiffness
for
straight
sprinting.
may be different than the optimal running-specific prosthetic stiffness for straight sprintFurthermore,
unilateral
lower-limb
amputee
long
jumpers
specific
ing.
Furthermore,
unilateral
lower-limb
amputee
long
jumperscould
couldbenefit
benefit from
from specific
eccentric strengthening of the hip and knee extensors to increase leg stiffness during the
pivot and horizontal velocities.

Sports 2021, 9, 89

6 of 15

2.5. Athletes with Visual Impairments
Reduced or absent visual input in athletes with a visual impairment results in a greater
reliance on the somatosensory and vestibular systems for postural control and orientation.
Compared to sighted horizontal jumpers, athletes with a visual impairment have a shorter
approach run, maintain or increase their speed in the last few strides of the approach,
and have an increased board contact time [33] in an attempt to generate as much vertical
impulse as possible, which is easier given their slower horizontal velocities compared to
sighted jumpers [33].
Changes to postural stability and proprioception with altered vision or a sensory
deficit may result in abnormal gait patterns in athletes with a visual impairment. The lack
of visual input during sprinting can reduce horizontal sprint speed. By incorporating kinesthetic training (exercises with unstable supports), improvements to neuromuscular control
of lower limbs and trunk stability may be an important factor in improving kinesthetic
awareness [34] and subsequent sprint speed. Therefore, practitioners working with athletes
with a visual impairment should incorporate physical assessments of postural and gait
imbalances, incorporate stability and proprioceptive training in sport-specific positions,
and implement strength programs focused on maximizing horizontal sprinting velocity.
In summary, practitioners and coaches working with Paralympic athletes competing
in a standing posture should consider potential limitations to generating the horizontal
and vertical impulses during their respective events in order to maximize horizontal sprint
speed (in the case of sprinting and jumping) and to improve take-off mechanics in the
horizontal jumps.
3. Sitting
In many summer Paralympic sports, athletes perform in a sitting position on a bike,
in a wheelchair (WC), in a boat, or on a horse. Here, we discuss the recent development of
mobility and performance tests used for different WC configurations associated with WC
rugby, tennis, and basketball.
3.1. Development of Mobility Performance Tests
For field-based WC sports, the ability to evaluate sport-specific mobility performance
will provide an indication to an athlete’s relative weaknesses and strengths, monitor overall
progress, or examine recovery from an injury. Since 2016, most of the research focused
on the development of different mobility tests and the evaluation of their associated validity and reliability. WC Basketball mobility scores were able to discriminate between
male/female and between the national and international levels with excellent test–retest
reliability [35], but they were unable to differentiate between low and high levels of disability. In WC Tennis, sprint ability and maneuverability capacity showed high inter-trial
reliability, while construct validity was achieved with successful discrimination between
junior and international player levels [36]. To improve classification objectivity in boccia,
dos Santos et al. [37] proposed a spasticity test with rapid passive movements to improve
objective classification across para-athletes with cerebral palsy. These tests allow practitioners to objectively quantify and monitor an athlete’s capacity, relative strengths and
weaknesses, progress, assess recovery from injury, or improve classification objectivity.
3.2. Classification Level, WC Configuration and Mobility Performance
Mobility performance is associated with eight key parameters, including classification
level, athlete experience, maximal isometric force, and WC configurations [38]. In WC Basketball, adding a mass to the WC creates a reduction in acceleration, and when distributed,
the mass reduces the angular kinematics [39]. These changes were not implemented, but
seat elevation enhances sprinting/turning performance while increasing rim grip has a
detrimental effect on sprint/turning performance. In WC Rugby, an athlete-specific seat
configuration has also been associated with improved sprint performance [40]. As such,
differences in propulsion kinematics should be considered for individualized WC configu-

Sports 2021, 9, 89

7 of 15

rations and training programs. Since optimum configuration is not always perceived [40],
an adequate adaptation period might be needed.
Haydon et al. [41] compared different classification categories in three-stroke acceleration. Sprint performance is reduced in high-disability players from a stationary compared
to a sport-specific active start. Surprisingly, this was not seen in the higher-point groups.
These results highlight the athlete-specific nature in test design and analyses with these
athletes and the need to consider testing modifications across disability groups. Throwing
boccia balls, discuses, shot puts, and javelins may require specific WC configurations to
enhance performance. Hyde et al. [42] showed that an assistive pole is associated with a
higher hand speed in WC throwing. Grip, trunk-flexion strength, and push/pull synergy
were also correlated with throwing distance. The use of an assistive pole should definitely
be considered in all WC throwing events.
For athletes who are lower-limb amputees, changing the seated configuration will
change the body centre of mass position, and the use of prostheses may improve the
leverage that the limb(s) can provide. For example, in para kayak, Ellis et al. [43] found
that when the prosthetic limb was removed, decrements in stroke rate, stroke speed, stroke
length, and overall power output were observed. Coaches should ensure the residual limb
is well supported in the boat to provide the maximum leverage for optimal propulsive
strength. Adjusting the mass distribution in both the frontal and sagittal planes will
also favor buoyancy and reduce hydrodynamic drag. In the case of bilateral lower-limb
amputees using a canoe or kayak, we recommend using both lower limb prostheses to
distribute the mass evenly and to provide adequate leverage to apply forces from the trunk
and upper limbs for efficient paddling.
3.3. Aerodynamic Improvements and Performance Enhancement
In addition to optimizing the performance factors of the athlete through physical training, improving the equipment can play a decisive role in enhancing performance in many
parasports. Propulsion of a WC, bike, or boat is limited by different sources of resistance including air/water, rolling, gravity, and mechanical friction. Paralympic athletes performing
on a bike/WC experience important resistance from aerodynamic drag while Paralympic
sports performed in a boat encounter mainly hydrodynamic drag. The air resistance is the
most important WC resistive force, especially at higher speeds. Aero/hydrodynamic resistance as well as the energy expenditure can be reduced by adopting a body/bike/boat/WC
configuration with minimal frontal area, more aero/hydrodynamic shape, and less surface
friction [44]. Using computational fluid dynamics, a lighter prosthetic design with 1 kg
reduction and a special body position were associated with a performance improvement
of 23 s over a 16.1 km time trial in individual [45,46] and tandem para-cycling [46]. This
lower drag and energy cost in amputee cyclists compared to able-bodied cyclists is not
present when the model removed one arm or one leg [46]. In para-athletes using hand
cycles, Mannion et al. [46] tested different arm-crank positions with computational fluid
dynamics and showed that the 9 o’clock arm-crank (relative to top-dead centre) produced
less aerodynamic drag compared to the 6 o’clock position. In WC sprinting, different
postures during the catch, release, and recovery phases have also been assessed using
computational fluid dynamics. After wind tunnel validation [47], higher drag during the
catch phase and minimal drag during the recovery phase were reported [44]. Adjusting
body configuration and equipment will contribute to reduced drag and improved WC and
para-cycling performance.

Sports 2021, 9, 89

8 of 15

3.4. Specific Training/Physical Preparation Modalities and Risk of Injury
In para-cyclists with or without a unilateral lower-limb amputation, Dyer [48] showed
no difference in 1 km time trial performance between groups, suggesting that the sound
limb of lower-limb amputee athletes has to further compensate for the contralateral loss to
achieve similar cycling performances. This may predispose para-cyclists with unilateral
lower-limb amputation to musculoskeletal injuries; the athletes may compensate for the
lack of contralateral pushing by increasing rectus/biceps femoris and medial gastrocnemius
muscle activity during the pulling phase [49]. Childers et al. [50] compared both the
prosthetic and sound sides and found gastrocnemius/rectus femoris compensations for
controlling the prosthetic socket. They also reported asymmetrical muscular and moment
contributions in para-cyclists. Goosey-Tolfrey et al. [51] tested the kinematics of WC Rugby
players during a 15 s sprint. Lower disability players reached greater peak speed and
peak power output compared to higher disability players. Propulsion asymmetries were
observed more often in lower disability players showing a greater demand for the arms
during WC propulsion.
WC Fencing athletes are classified into three categories (A, B, C) with respect to
their movement capacity. A shorter lunge time between Category A and Category B
fencers [52] supports the role of the external abdominal oblique and latissimus dorsi
muscles as effective postural muscles during fencing attacks. In WC Rugby, a 3 vs. 3
training modality is associated with moderate improvements in WC speed and on the
number of high-speed events compared to regular game simulation drills [53]. Thus,
reducing the number of players on the court should be considered to improve WC speed.
Both the kinetic and kinematic variables can affect Paralympic paddling performance,
including the ability to move the trunk, pelvis, and legs. Leg/trunk/arms para-kayakers
show less rotation/flexion of the trunk/pelvis and less hip, knee, and ankle flexion during
paddling, contributing to lower power outputs in comparison to able-bodied kayakers [54].
These studies support the importance of specific physical preparation programs for
injury prevention and performance enhancement in Paralympic athletes. Physical preparation should take these asymmetries into account. Athletes with minimal contribution
from the lower limbs may benefit from the use of functional electrical stimulation protocols
during training to assist with knee flexion/extension movements and improve cardiovascular function [55]. However, the current amplitude, duration, and frequency are among
the many parameters to consider when using functional electrical stimulation [56] and
may not be sufficient to elicit meaningful changes in muscle force or sport performance. It
is also important to consider athletes with asymmetric profiles (cerebral palsy, unilateral
amputation), as they are likely to achieve different force applications/joint movements
between sides. Therefore, we suggest that coaches focus on improving sport-specific joint
ROM and (near) symmetrical force application to improve power outputs in kayak performance. Importantly, the physical preparation of all Paralympic athletes should be category
(and thus disability) specific to reduce the incidence of injury and optimize performance.
4. Horizontal
Two Paralympic sports utilize a horizontal body position, Paralympic Powerlifting and
Paralympic Swimming. Paralympic Powerlifting consists of the adapted bench press, with
minimal research available outside recommendations for grip width improving muscle
recruitment and activation [57], and potentially reducing risk of injury [58]. This is contrary
to the Para-swimming literature, which has accumulated a number of timely and relevant
articles published since 2016 to evaluate.

Sports 2021, 9, 89

9 of 15

4.1. Swimming
Muscular strength and power are key determinants of improved propulsion during
start and free-swimming [59]. Para-swimmers may experience a loss in muscle mass,
rate of force development, stability, or coordination affecting swim-start performances.
Differences in the anthropometric profile of para-swimmers can also affect their ability to
produce symmetrical forces between limbs and may alter drag. Coaches working with
para-swimmers need to identify individual characteristics influencing propulsion and drag,
acknowledging that the swim-start in para-swimmers is influenced by the severity and
type of disability [60].
4.2. Effect of Impairment on Swim-Start and Free-Swim Velocities
Assessment of four specific measures of the swim-start highlight distinctive priorities
for coaches working with para-swimmers: time, distance, velocity, and force. We suggest
that the fastest swim start maximizes horizontal range, resulting from high impulse (and
thus high velocity) with low block contact time. Not surprisingly, para-swimmers with
greater function are capable of producing a better start and faster free swim speeds [38].
In comparison to able-bodied swimmers, para-swimmers exhibit a greater variability
in the start execution, with some adopting compensational mechanisms to help deliver
a stable performance. Athletes with neurological impairments tend to show a lower
consistency in start performance [61], needing intensive and repetitive practice to develop
well-coordinated muscular patterns and increase maximal voluntary activation [62].
Free swim speed is critical to overall performance regardless of disability, as it accounts
for 67–75% of the variation in 50 m swim performance [60]. This proportion becomes greater
the longer the race. Lower velocities during block and underwater phases are associated
with a slower time to 15 m, specifically affecting swimmers with lower body or highseverity disabilities who spend a smaller percentage of time in the underwater phase [60].
Swimmers with a visual impairment may lose their orientation or ability to define their
position in the water, resulting in significantly slower free-swim speeds [63].
4.3. Asymmetries in Para-Swimming
In able-bodied freestyle swimming, 90% of the propulsion is from the upper limbs [64].
It is also a significant contributor to the propulsion in para-swimmers. Hand and forearm
length are the most important factors in 100 m freestyle performance in para-swimmers [65].
Bilateral mean hand force and swimming velocity are highly correlated across paraswimming classifications, where para-swimmers exhibiting an asymmetrical anthropometric profile or more severe physical impairment typically generate lower forces and
velocities [66,67]. For a unilateral arm-amputee swimmer, the reduced limb length and surface area will affect the ability to generate propulsive forces and reduce stroke length [66].
In addition, the lag time between the propulsive forces will require an increase in the stroke
frequency to increase free swim velocity, increasing the swimmer’s overall mechanical
work and energy cost to overcome the hydrodynamic drag [68]. Therefore, coaches should
identify different technical skills to offset the asymmetric propulsive forces and asymmetric
roll amplitude between the affected and unaffected sides [69].
4.4. Drag Factors
A physical impairment may affect the ability to generate propulsive forces to overcome
the drag and inertial parameters in swimming. Payton et al. [70] found higher active
and passive drag in para-swimmers with central motor and neuromuscular impairments
when compared to able-bodied swimmers. Impairments in motor coordination or ROM
predispose athletes to increased form drag, with para-swimmers exhibiting significantly
reduced ROM compared to their able-bodied peers [71]. Unique head positions and
postures may also affect the streamline position and thus increase form drag. Interestingly,
para-swimmers with anthropometric impairments (limb deficiency, short stature, impaired
ROM) show similar active and passive drag to non-disabled swimmers and swimmers

Sports 2021, 9, 89

10 of 15

from different sport classes [70]. This suggests that para-swimmers with anthropometric
impairments are primarily limited by their ability to produce power rather than overcoming
high active or passive drag. It is possible that these swimmers create less disturbance in
the water with the increasing severity of impairment due to partial or full absence of a
leg-kick or arm stroke during freestyle swimming. Although the lower limbs contribute
less to propulsion than the upper body, the legs may still contribute to generating lift forces,
thereby decreasing trunk inclination and form drag [72]. Para-swimmers with impairments
to the lower limbs may need a greater emphasis on hip and leg strength, especially those
in lower sport classes where drag plays a greater role on performance [73]. In response
to understanding the importance of drag on athletes with varying impairments, World
Para-Swimming has recently announced that drag will be one of the factors considered as
part of the Functional Classification system process [70].
5. Conclusions and Future Directions
This narrative review critically evaluated the relevant biomechanical research published since 2016 and has expanded on the systematic review by Morriën [1] in two impactful ways to the Paralympic sport practitioner: we have summarized and critically evaluated
the relevant Paralympic biomechanical literature from a practitioner-specific perspective.
This review further highlights the athlete-specific biomechanical considerations required
to optimize performance (Table 2). These specific considerations include disability-and
event-specific training modalities and equipment configurations to optimize performance
and reduce the incidence of injury. Future directions include the use of Paralympic sport
biomechanics to contribute to the objective classification of Paralympic athletes and the examination of longitudinal changes in Paralympic biomechanics as a result of the systematic
and well-documented training studies aimed at optimizing Paralympic performance.

Sports 2021, 9, 89

11 of 15

Table 2. Practical and special consideration for supporting Paralympic athletes.
Key Intervention
RSP alignment relative to sagittal plane

Potential Impact of Intervention

Considerations, Benefits, Knowledge Gaps

 Increased step frequency

 Higher top and average running speed over 100 m.

 Higher propulsive impulse

RSP height

 Longer stride length

 Maximal allowable standing height regulated by IPC

 Lower stride frequency

 CAS disallowed Blake Leeper to compete in 2020(1) Olympics based on RSP height
 Moment of inertia of RSP dictates changes in stride frequency, which may be different than

RSP stiffness

Higher energy return compared to compliant blade

Intensive and repetitive practice for those athletes with
neurological impairments (reduced motor control)

 Improved consistency in movement execution, reduced

Use of stability and proprioceptive training for VI
athletes

 Improved kinesthetic awareness, neuromuscular control,

Strength Training for injury prevention in athletes with
upper body predominant propulsion (WC sports,
swimmers with LLA, etc.)
Athlete-specific equipment configurations (wheelchair,
boat, prosthesis, etc)

 Symmetrical force application between sides will increase
power output.

movement variability and compensational movements.

and orientation.

 May reduce the chances of overuse injury
 Improvements to force application, propulsion efficiency,

drag, range of motion and possibly injury prevention.
 Quantify and monitor an athlete’s relative weaknesses and

Evaluate sport-specific mobility in wheelchair athletes

strengths, overall progress, recovery from injury, or improve
classification objectivity.

Hip and knee extensor muscle strengthening in
Paralympic sprinters, long jumpers, and
para-swimmers with lower limb impairments

 Increased joint angular velocities, external joint powers

and step length during the initial acceleration phase of
sprinting.
 Improvements to horizontal take-off velocities during the
long jump
 Improvements in hip and leg strength may contribute to

generating lift forces, and thereby decreasing trunk
inclination and form drag in Para-swimmers

intact limb(s)
 Energy “return” is always <100%, and less than intact limbs since RSPs cannot generate
positive mechanical power
 Energy storage and return does not incur a metabolic cost, like in intact limbs
 Intensive practice may improve muscle coordination and maximal voluntary activation in
these individuals. Eg. Higher impulses over short time periods during the block phase will
improve swim start performance
 VI Athletes may have subconscious fears to movement disruption or fear of injury during
training and competition. Methods to help overcome these fears may lead to increased running
speeds.
 Athletes with a greater demand on particular limb(s) may show greater propulsion
asymmetries and develop compensations for control. Coaches should identify different
technical skills, strength trainers should identify strength imbalances to offset the asymmetric
force application.
 Athlete-specific body configurations and equipment choices can be made from objective
biomechanical inputs and lead to performance enhancement.
 The tests need to be valid and reliable; discriminate between athletes of different sex,

competition level, and level of impairment

 In CP, hip joint performs negative work due to increased passive and active joint stiffness.
 In unilateral LLA long jumpers, specific eccentric strengthening of hip and knee extensors can

help increase leg stiffness during the pivot.
 Drag can differ appreciably between athletes of different sport classes. An improved

streamline position will reduce drag and improve performance.

Abbreviations: Court of Arbitration for Sport (CAS); Cerebral Palsy (CP); Lower leg amputee (LLA); Running-specific prosthetic (RSP); Visual impairment (VI).

Sports 2021, 9, 89

12 of 15

Author Contributions: Conceptualization, J.R.F., T.G. and F.P.; writing—original draft preparation,
J.R.F., T.G. and F.P.; writing—review and editing, J.R.F., T.G. and F.P. All authors have read and agreed
to the published version of the manuscript.
Funding: The authors have not declared a specific grant for this research from any funding agency
in the public, commercial, or not-for-profit sectors.
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: Data sharing not applicable. No new data were created or analyzed in
this study. Data sharing is not applicable to this article.
Acknowledgments: We thank Christopher R. West, Trent Stellingwerff, Melissa A. La Croix, and
Lindsay Musalem for their constructive feedback during the review of this manuscript. We also
thank the members of the Own the Podium Paralympic Professional Development Working Group
for their support during the conception, design, and writing of the initial draft of the manuscript.
Conflicts of Interest: The authors declare that they have no conflict of interest.

References
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.

20.

Morriën, F.; Taylor, M.J.D.; Hettinga, F.J. Biomechanics in Paralympics: Implications for Performance. Int. J. Sports Physiol. Perform.
2017, 12, 578–589. [CrossRef]
Weyand, P.G.; Sandell, R.F.; Prime, D.N.L.; Bundle, M.W. The biological limits to running speed are imposed from the ground up.
J. Appl. Physiol. 2010, 108, 950–961. [CrossRef]
Weyand, P.G.; Sternlight, D.B.; Bellizzi, M.J.; Wright, S. Faster top running speeds are achieved with greater ground forces not
more rapid leg movements. J. Appl. Physiol. 2000, 89, 1991–1999. [CrossRef] [PubMed]
Prince, F.; Allard, P.; McFadyen, B.J.; Aissaoui, R. Comparison of gait between young adults fitted with the space foot and
nondisabled persons. Arch. Phys. Med. Rehabil. 1993, 74, 1369–1376. [CrossRef]
Beck, O.N.; Taboga, P.; Grabowski, A. Characterizing the Mechanical Properties of Running-Specific Prostheses. PLoS ONE 2016,
11, e0168298. [CrossRef] [PubMed]
Czerniecki, J.M.; Gitter, A.; Munro, C. Joint moment and muscle power output characteristics of below knee amputees during
running: The influence of energy storing prosthetic feet. J. Biomech. 1991, 24, 63–75. [CrossRef]
Fletcher, J.R.; MacIntosh, B.R. Achilles tendon strain energy in distance running: Consider the muscle energy cost. J. Appl. Physiol.
2015, 118, 193–199. [CrossRef]
Beck, O.N.; Grabowski, A. Athletes With Versus Without Leg Amputations: Different Biomechanics, Similar Running Economy.
Exerc. Sport Sci. Rev. 2019, 47, 15–21. [CrossRef]
Beck, O.N.; Grabowski, A. The biomechanics of the fastest sprinter with a unilateral transtibial amputation. J. Appl. Physiol. 2018,
124, 641–645. [CrossRef]
Grabowski, A.M.; McGowan, C.P.; McDermott, W.J.; Beale, M.T.; Kram, R.; Herr, H.M. Running-specific prostheses limit
ground-force during sprinting. Biol. Lett. 2009, 6, 201–204. [CrossRef]
McGowan, C.P.; Grabowski, A.; McDermott, W.J.; Herr, H.M.; Kram, R. Leg stiffness of sprinters using running-specific prostheses.
J. R. Soc. Interface 2012, 9, 1975–1982. [CrossRef]
Mengelkoch, L.J.; Kahle, J.T.; Highsmith, M.J. Energy costs and performance of transfemoral amputees and non-amputees during
walking and running. Prosthet. Orthot. Int. 2017, 41, 484–491. [CrossRef] [PubMed]
Weyand, P.G.; Bundle, M.W.; McGowan, C.P.; Grabowski, A.; Brown, M.B.; Kram, R.; Herr, H. The fastest runner on artificial legs:
Different limbs, similar function? J. Appl. Physiol. 2009, 107, 903–911. [CrossRef] [PubMed]
Nolan, L. Carbon fibre prostheses and running in amputees: A review. Foot Ankle Surg. 2008, 14, 125–129. [CrossRef]
Taboga, P.; Beck, O.N.; Grabowski, A.M. Prosthetic shape, but not stiffness or height, affects the maximum speed of sprinters with
bilateral transtibial amputations. PLoS ONE 2020, 15, e0229035. [CrossRef] [PubMed]
Kram, R.; Grabowski, A.M.; McGowan, C.P.; Brown, M.B.; Herr, H.M. Counterpoint: Artificial legs do not make artificially fast
running speeds possible. J. Appl. Physiol. 2010, 108, 1012–1014. [CrossRef] [PubMed]
Weyand, P.G.; Bundle, M.W. Point: Counterpoint: Artificial limbs do/do not make artificially fast running speeds possible. J.
Appl. Physiol. 2010. [CrossRef]
Drake, J.Q.; Leeper, B.; Jeffrey Kessler, R.L.; Feher, D.; Stepek, M.J.; Lefranc-Barthe, M. CAS 2020/A/6807 Blake Leeper v. International
Association of Athletics Federations; Court of Arbitration for Sport: Lausanne, Switzerland, 2020.
Migliore, G.L.; Petrone, N.; Hobara, H.; Nagahara, R.; Miyashiro, K.; Costa, G.F.; Gri, A.; Cutti, A.G. Innovative alignment of
sprinting prostheses for persons with transfemoral amputation: Exploratory study on a gold medal Paralympic athlete. Prosthetics
Orthot. Int. 2021, 45, 46–53. [CrossRef]
Greene, P.R. Running on Flat Turns: Experiments, Theory, and Applications. J. Biomech. Eng. 1985, 107, 96–103. [CrossRef]

Sports 2021, 9, 89

21.
22.
23.
24.

25.
26.

27.

28.
29.
30.
31.

32.

33.
34.

35.

36.

37.

38.
39.

40.
41.
42.
43.
44.

13 of 15

Taboga, P.; Kram, R.; Grabowski, A. Maximum-speed curve-running biomechanics of sprinters with and without unilateral leg
amputations. J. Exp. Biol. 2016, 219, 851–858. [CrossRef]
Pingel, J.; Bartels, E.M.; Nielsen, J.B. New perspectives on the development of muscle contractures following central motor lesions.
J. Physiol. 2016, 595, 1027–1038. [CrossRef]
Wiley, M.E.; Damiano, D.L. Lower-extremity strength profiles in spastic cerebral palsy. Dev. Med. Child Neurol. 1998, 40, 100–107.
[CrossRef] [PubMed]
Smith, L.R.; Lee, K.S.; Ward, S.R.; Chambers, H.G.; Lieber, R.L. Hamstring contractures in children with spastic cerebral palsy
result from a stiffer extracellular matrix and increased in vivo sarcomere length. J. Physiol. 2011, 589, 2625–2639. [CrossRef]
[PubMed]
Condliffe, E.; Jeffery, D.T.; Emery, D.J.; Gorassini, M.A. Spinal inhibition and motor function in adults with spastic cerebral palsy.
J. Physiol. 2016, 594, 2691–2705. [CrossRef] [PubMed]
Geertsen, S.S.; Kirk, H.; Lorentzen, J.; Jorsal, M.; Johansson, C.B.; Nielsen, J.B. Impaired gait function in adults with cerebral
palsy is associated with reduced rapid force generation and increased passive stiffness. Clin. Neurophysiol. 2015, 126, 2320–2329.
[CrossRef] [PubMed]
Bezodis, I.N.; Cowburn, J.; Brazil, A.; Richardson, R.; Wilson, C.; Exell, T.A.; Irwin, G. A biomechanical comparison of initial
sprint acceleration performance and technique in an elite athlete with cerebral palsy and able-bodied sprinters. Sports Biomech.
2018, 19, 189–200. [CrossRef] [PubMed]
Damiano, D.L.; Martellotta, T.L.; Sullivan, D.J.; Granata, K.P.; Abel, M.F. Muscle force production and functional performance in
spastic cerebral palsy: Relationship of cocontraction. Arch. Phys. Med. Rehabil. 2000, 81, 895–900. [CrossRef]
Gross, R.; Leboeuf, F.; Hardouin, J.-B.; Lempereur, M.; Perrouin-Verbe, B.; Remy-Neris, O.; Brochard, S. The influence of gait
speed on co-activation in unilateral spastic cerebral palsy children. Clin. Biomech. 2013, 28, 312–317. [CrossRef]
Ikeda, A.J.; Abel, M.F.; Granata, K.P.; Damiano, D.L. Quantification of cocontraction in spastic cerebral palsy. Electromyogr. Clin.
Neurophysiol. 1998, 38, 497–504. [CrossRef]
Willwacher, S.; Funken, J.; Heinrich, K.; Müller, R.; Hobara, H.; Grabowski, A.M.; Brüggemann, G.-P.; Potthast, W. Elite long
jumpers with below the knee prostheses approach the board slower, but take-off more effectively than non-amputee athletes. Sci.
Rep. 2017, 7, 16058. [CrossRef] [PubMed]
Funken, J.; Willwacher, S.; Heinrich, K.; Müller, R.; Hobara, H.; Grabowski, A.M.; Potthast, W. Long jumpers with and without a
transtibial amputation have different three-dimensional centre of mass and joint take-off step kinematics. R. Soc. Open Sci. 2019,
6, 190107. [CrossRef]
Torralba, M.A.; Padullés, J.M.; Losada, J.L.; López, J.L. Spatiotemporal characteristics of motor actions by blind long jump athletes.
BMJ Open Sport Exerc. Med. 2017, 3, e000252. [CrossRef]
Kozina, Z.; Chaika, O.; Prokopenko, I.; Zdanyuk, V.; Kniaz, H.; Proskurnia, O.; Chernozub, A.; Shkrebtii, Y.; Romantsova, Y.
Change in the biomechanical characteristics of running as a result of an individual 1-year program for training an elite athlete
with visual impairment for Paralympic Games. Physiother. Q. 2020, 28, 21–31. [CrossRef]
de Witte, A.M.H.; Hoozemans, M.J.M.; Berger, M.A.M.; van der Slikke, R.M.A.; van der Woude, L.H.V.; Veeger, D. Development,
construct validity and test–retest reliability of a field-based wheelchair mobility performance test for wheelchair basketball. J.
Sports Sci. 2018, 36, 23–32. [CrossRef]
Rietveld, T.; Vegter, R.J.K.; van der Slikke, R.M.A.; Hoekstra, A.E.; van der Woude, L.H.V.; de Groot, S. Wheelchair mobility
performance of elite wheelchair tennis players during four field tests: Inter-trial reliability and construct validity. PLoS ONE 2019,
14, e0217514. [CrossRef]
dos Santos, E.D.L.; Vara, M.D.F.F.; Ranciaro, M.; Zelaga, G.T.; Gomes, A.M.P.; Bini, I.C.; Neto, G.N.N.; Krueger, E.; Nohama, P.
Mechanomyography Spasticity Assessment of Flexor and Extensor Wrist Muscles for the Classification of Boccia Athletes in Para
Sports: A Pilot Study. IFMBE Proc. 2020, 75, 1184–1190. [CrossRef]
Veeger, T.T.; De Witte, A.M.; Berger, M.A.; van der Slikke, R.M.; Veeger, D.H.; Hoozemans, M.J. Improving mobility performance
in wheelchair basketball. J. Sport Rehabil 2019, 28, 59–66. [CrossRef] [PubMed]
Van Der Slikke, R.M.A.; De Witte, A.M.H.; Berger, M.A.M.; Bregman, D.J.J.; Veeger, D.J.H.E.J. Wheelchair mobility performance
enhancement by changing wheelchair properties: What is the effect of grip, seat height, and mass? Int. J. Sports Physiol. Perform.
2018, 13, 1050–1058. [CrossRef] [PubMed]
Haydon, D.S.; Pinder, R.A.; Grimshaw, P.N.; Robertson, W.S.P. Wheelchair Rugby chair configurations: An individual, Robust
design approach. Sport Biomech. 2019, 1–16. [CrossRef]
Haydon, D.S.; Pinder, R.A.; Grimshaw, P.N.; Robertson, W.S. Test design and individual analysis in wheelchair rugby. J. Sci. Med.
Sport 2018, 21, 1262–1267. [CrossRef] [PubMed]
Hyde, A.; Hogarth, L.; Sayers, M.; Beckman, E.; Connick, M.J.; Tweedy, S.; Burkett, B. The impact of an assistive pole, seat
configuration, and strength in paralympic seated throwing. Int. J. Sports Physiol. Perform. 2017, 12, 977–983. [CrossRef]
Ellis, S.; Callaway, A.; Dyer, B. The influence of lower-limb prostheses technology on Paracanoeing time-trial performance. Disabil.
Rehabil. Assist. Technol. 2018, 13, 568–574. [CrossRef]
Forte, P.; Marinho, D.A.; Morais, J.E.; Morouço, P.G.; Barbosa, T.M. The variations on the aerodynamics of a world-ranked
wheelchair sprinter in the key-moments of the stroke cycle: A numerical simulation analysis. PLoS ONE 2018, 13, e0193658.
[CrossRef]

Sports 2021, 9, 89

45.
46.
47.
48.
49.

50.
51.

52.
53.
54.
55.
56.
57.

58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.

14 of 15

Dyer, B.T.; Deans, S.A. Swimming with limb absence: A systematic review. J. Rehabil. Assist. Technol. Eng. 2017, 4. [CrossRef]
[PubMed]
Dyer, B.; Disley, B.X. The aerodynamic impact of a range of prostheses designs when cycling with a trans-tibial amputation.
Disabil. Rehabil. Assist. Technol. 2020, 15, 577–581. [CrossRef] [PubMed]
Mannion, P.; Toparlar, Y.; Blocken, B.; Hajdukiewicz, M.; Andrianne, T.; Clifford, E. Impact of pilot and stoker torso angles in
tandem para-cycling aerodynamics. Sport Eng. 2019, 22, 1–10. [CrossRef]
Dyer, B. The impact of lower-limb prosthetic limb use in international C4 track para-cycling. Disabil. Rehabil. Assist. Technol. 2018,
13, 798–802. [CrossRef] [PubMed]
Watanabe, K.; Yamaguchi, Y.; Fukuda, W.; Nakazawa, S.; Kenjo, T.; Nishiyama, T. Neuromuscular activation pattern of lower
extremity muscles during pedaling in cyclists with single amputation of leg and with two legs: A case study. BMC Res. Notes
2020, 13, 299. [CrossRef]
Childers, W.L.; Gallagher, T.P.; Duncan, J.C.; Taylor, D.K. Modeling the effect of a prosthetic limb on 4-km pursuit performance.
Int. J. Sports Physiol. Perform. 2015, 10, 3–10. [CrossRef] [PubMed]
Goosey-Tolfrey, V.L.; Vegter, R.J.K.; Mason, B.S.; Paulson, T.A.; Lenton, J.P.; Van Der Scheer, J.W.; van der Woude, L.H. Sprint
performance and propulsion asymmetries on an ergometer in trained high- and low-point wheelchair rugby players. Scand. J.
Med. Sci. Sports 2018, 28, 1586–1593. [CrossRef]
Borysiuk, Z.; Nowicki, T.; Piechota, K.; Błaszczyszyn, M. Neuromuscular, Perceptual, and Temporal Determinants of Movement
Patterns in Wheelchair Fencing: Preliminary Study. Biomed. Res. Int. 2020. [CrossRef]
Rhodes, J.M.; Mason, B.S.; Paulson, T.A.W.; Goosey-Tolfrey, V.L. Altering the speed profiles of wheelchair rugby players with
game-simulation drill design. Int. J. Sports Physiol. Perform. 2018, 13, 37–43. [CrossRef]
Bjerkefors, A.; Rosén, J.S.; Tarassova, O.; Arndt, A. Three-dimensional kinematics and power output in elite para-kayakers and
elite able-bodied flat-water kayakers. J. Appl. Biomech. 2019, 35, 93–100. [CrossRef]
Andrews, B.; Gibbons, R.; Wheeler, G. Development of Functional Electrical Stimulation Rowing: The Rowstim Series. Artif.
Organs. 2017, 41, E203–E212. [CrossRef] [PubMed]
Lake, D.A. Neuromuscular Electrical Stimulation: An Overview and its Application in the Treatment of Sports Injuries. Sports
Med. 1992, 13, 320–336. [CrossRef]
dos Santos, M.D.M.; Aidar, F.J.; de Souza, R.F.; dos Santos, J.L.; da Silva de Mello, A.; Neiva, H.P.; Marinho, D.A.; Marques, M.C.
Does the Grip Width Affect the Bench Press Performance of Paralympic Powerlifters? Int. J. Sports Physiol. Perform. 2020, 15,
1252–1259. [CrossRef]
Green, C.M.; Comfort, P. The affect of grip width on bench press performance and risk of injury. Strength Cond. J. 2007, 29, 10–14.
[CrossRef]
Sharp, R.L.; Troup, J.P.; Costill, D.L. Relationship between power and sprint freestyle swimming. Med. Sci. Sport Exerc. 1982, 14,
53–56. [CrossRef] [PubMed]
Dingley, A.A.; Pyne, D.; Burkett, B. Phases of the Swim-start in Paralympic Swimmers Are Influenced by Severity and Type of
Disability. J. Appl. Biomech. 2014, 30, 643–648. [CrossRef] [PubMed]
Van Caekenberghe, I.; Payton, C. Kinetics and Kinematics of the Block Phase of Elite Para Swimming Starts. In Proceedings of the
35th Conference of the International Society of Biomechanics in Sports, Cologne, Germany, 14–18 June 2017; pp. 855–858.
Nakazawa, K.; Obata, H.; Nozaki, D.; Uehara, S.; Celnik, P. “Paralympic Brain”. Compensation and Reorganization of a Damaged
Human Brain with Intensive Physical Training. Sports 2020, 8, 46. [CrossRef] [PubMed]
Malone, L.A.; Sanders, R.H.; Schiltz, J.H.; Steadward, R.D. Effects of visual impairment on stroke parameters in Paralympic
swimmers. Med. Sci. Sports Exerc. 2001, 33, 2098–2103. [CrossRef]
Deschodt, J.V.; Arsac, L.M.; Rouard, A.H. Relative contribution of arms and legs in humans to propulsion in 25-m sprint
front-crawl swimming. Eur. J. Appl. Physiol. Occup. Physiol. 1999, 80, 192–199. [CrossRef] [PubMed]
Hogarth, L.; Payton, C.; Van De Vliet, P.; Connick, M.; Burkett, B. A novel method to guide classification of para swimmers with
limb deficiency. Scand. J. Med. Sci. Sports 2018, 28, 2397–2406. [CrossRef] [PubMed]
Hogarth, L.; Burkett, B.; Van De Vliet, P.; Payton, C. Maximal Fully Tethered Swim Performance in Para Swimmers with Physical
Impairment. Int. J. Sports Physiol. Perform. 2020, 15, 816–824. [CrossRef] [PubMed]
Dingley, A.A.; Pyne, D.; Burkett, B. Dry-land bilateral hand-force production and swimming performance in paralympic
swimmers. Int. J. Sports Med. 2014, 35, 949–953.
Figueiredo, P.; Willig, R.; Alves, F.; Vilas-Boas, J.P.; Fernandes, R.J. Biophysical Characterization of a Swimmer with a Unilateral
Arm Amputation: A Case Study. Int. J. Sports Physiol. Perform. 2014, 9, 1050–1053. [CrossRef]
Gonjo, T.; Kishimoto, T.; Sanders, R.; Saito, M.; Takagi, H. Front crawl body roll characteristics in a Paralympic medallist and
national level swimmers with unilateral arm amputation. Sports Biomech. 2019, 1–17. [CrossRef]
Payton, C.; Hogarth, L.; Burkett, B.; van de Vliet, P.; Lewis, S.; Oh, Y.-T. Active Drag as a Criterion for Evidence-based Classification
in Para Swimming. Med. Sci. Sports Exerc. 2020, 52, 1576–1584. [CrossRef]
Nicholson, V.P.; Spathis, J.; Hogarth, L.W.; Connick, M.J.; Beckman, E.M.; Tweedy, S.M.; Payton, C.J.; Burkett, B.J. Establishing the
reliability of a novel battery of range of motion tests to enable evidence-based classification in Para Swimming. Phys. Ther. Sport
2018, 32, 34–41. [CrossRef]

Sports 2021, 9, 89

72.
73.

15 of 15

Gourgoulis, V.; Boli, A.; Aggeloussis, N.; Toubekis, A.; Antoniou, P.; Kasimatis, P.; Vezos, N.; Michalopoulou, M.; Kambas, A.;
Mavromatis, G. The effect of leg kick on sprint front crawl swimming. J. Sports Sci. 2013, 32, 278–289. [CrossRef]
Oh, Y.-T.; Burkett, B.; Osborough, C.; Formosa, D.; Payton, C. London 2012 Paralympic swimming: Passive drag and the
classification system. Br. J. Sports Med. 2013, 47, 838–843. [CrossRef] [PubMed]