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The Open Sports Medicine Journal, 2011, 5, 1-11 1
1874-3870/11 2011 Bentham Open
Open Access
Strength and Conditioning Considerations for Elite Snowboard Half Pipe
Jonathon Turnbull*,1,2, Justin W.L. Keogh2 and Andrew E. Kilding2
1New Zealand Academy of Sport – Winter Performance Programme, P.O. Box 395, Wanaka, New Zealand
2Sports Performance Research Institute New Zealand, School of Sport and Recreation, AUT University, Private Bag
92006, Auckland, 1142, New Zealand
Abstract: Snowboarding Halfpipe (HP) is a winter action sport which has progressed from being a recreational snow
activity to a high performance snow sport such as traditional downhill or Nordic skiing. Like figure skating, gymnastics
and diving, performance in the snowboard HP is subjectively assessed by a number of judges. The marking criteria focus
on jump height (amplitude) and trick difficulty as the primary technical aspects. However, overall style and the
appearance of effortless motion are also essential components of a well scored run. While HP performance is very
technical in nature, considerable physical capabilities are required in order to maximize jump amplitude and remain injury
free. This paper examines the scientific basis of the HP to highlight the role that sports scientists and strength and
conditioners can play in this sport. Challenges that these practitioners may experience with these athletes are also
discussed. Further research is required to characterize the physical capacities of elite HP snowboarders and how these
compare to the stresses that training and competing may place on the human body. Such information may allow strength
and conditioning coaches and sports scientists to develop more specific conditioning programs and to have a clearer
understanding of the volume, intensity and mode of training athletes require and can tolerate in order to optimize their HP
performance.
Keywords: Amplitude, eccentric, halfpipe, landing, snowboarding, takeoff.
AN EMERGING PERFORMANCE SPORT
Modern competitive snowboarding was born in the US in
the 1960’s. Since this time snowboarding as a culture and
recreational pursuit has developed exponentially and is today
one of the fastest growing sports internationally.
Snowboarding’s place as a performance sport was
highlighted by its inclusion in the 1998 Nagano Winter
Olympics. In relation to traditional winter sports of Alpine or
Nordic skiing, the standard of performance in snowboarding
may improve at a faster rate due to its infancy as an Olympic
sport and the exposure it is getting as a competitive sport.
While this expected improvement will likely be multi-
factorial in nature, this paper postulates that strength and
conditioning coaches and sports scientists can contribute
substantially to this improvement.
Current practices of elite snowboarders appear varied in
nature and there is often stark contrast between the practices
of different teams. In saying this there appears to be a
transitioning from very high volume but low specificity
training (for example freeriding and skateboarding) to more
purposeful strength and conditioning practices born in many
instances initially out of ski racing programmes The purpose
of this paper is to describe the biomechanical requirements
of an elite snowboard Halfpipe (HP) rider that sports
scientists and strength and conditioners may need to consider
when working with these individuals.
*Address correspondence to this author at the New Zealand Academy of
Sport – Winter Performance Programme, P.O. Box 395, Wanaka, New
Zealand; Tel: +64 21 2227246; E-mail: Jon_T@xtra.co.nz
WHAT IS SNOWBOARD HALFPIPE?
Snowboard HP is one of two sub-disciplines of
snowboarding (the other being Snowboarder-Cross) which
have gained Winter Olympic status. A HP is a trough-type
feature made either entirely of snow or with a base of shaped
earth (Fig. 1). Competitive “runs” take around 20-30 seconds
and involve 6-8 “hits” where tricks are performed. While a
substantial anaerobic component likely contributes to each
individual run, long repetitive days of hiking up the pipe in
alpine environments and over long seasons also requires
significant aerobic fitness [1, 2].
A typical HP run starts on the entry ramp several meters
upslope of the pipe. The rider “drops in” from either side
after leaving the entry ramp. The rider will drop into the
eccentric transition (ET) just below the vertical (where the
pipe wall is vertical), crossing the flat before entering the
concentric transition (CT). The rider sets up for a trick as
they enter the CT, aiming to initiate the trick as close to the
lip as possible. Once the rider is in the air, utilising the
angular momentum gained by setting up in the CT, they will
rotate through several axes about their centre of mass (CoM),
depending on the trick. Tricks can be on or off axes (off axis
tricks are termed ‘corked tricks’), inverted, and on front side
(toeside), or backside (heelside) during take-off or landing,
depending on how the rider enters the pipe. Fig. (2) shows a
typical takeoff, inversion, rotation and landing of a
backcountry jump – similar to the positions of a halfpipe.
Snowboard HP contains areas of interest for many
individuals in the sports science and medicine fraternities.
Biomechanically, and from a motor learning perspective, HP
2 The Open Sports Medicine Journal, 2011, Volume 5 Turnbull et al.
is a skill-based event requiring significant kinaesthetic
awareness and the absorportion and generation of force in a
variety of “uncommon” anatomical positions. Riding
positions incorporate significant knee internal rotation and
adduction and ankle pronation. From an injury and
conditioning perspective, landings occur from large heights
and are often characterised by twisted and flexed spinal
postures, factors that significantly increase spinal load [3].
The alpine conditions of HP and the length of the training
day and season required to develop and refine technical
skills would also make HP interesting to exercise
physiologists.
Fig. (1). Photographic and Diagrammatic Representation of a Snowboard Halfpipe. Halfpipe usually have a fall line gradient of 15-200. For
the purposes of this review the Transition will be split in to the Eccentric Transition, where the rider drops into the pipe and sustains forces,
and the Concentric Transition where the rider prepares to takeoff from the pipe sustaining isometric and/or concentric forces.
Fig. (2). Front 5’ Melon trick off a backcountry jump. Melon Grab (front hand grabbing the heel-side edge behind the front foot and spinning
540deg counter clockwise.
Strength and Co nditioning Considerations for Elite Snowboard Half Pipe The Open Sports Medicine Journal, 2011, Volume 5 3
Judging Criteria for Snowboard Halfpipe
Similar to figure skating, diving and gymnastics,
performance in snowboard HP lacks specific objective
measurement. While each trick is judged based upon its
place and difficulty in the run, tricks of significant
amplitude, large rotation and fluid natural movement which
are off the normal vertical axis (normal forces are those
acting with gravity towards the horizontal), will generally be
judged highly [4, 5]. The judging criteria of the Federation
International de’ Ski (FIS) have also developed over the last
5 years to incorporate as much “rider expression” as
possible. The most recent judging criteria is outlined in Fig.
(3) [6].
Direction and Quality of Literature: Previous Methods vs
Current Trends
Despite its rapid rise in recreational and competitive arenas,
snowboarding HP has received very little attention in the
scientific literatur e. Ex cep t for a very recent pro liferation of
injury reports, several computer game simulation discussions,
and a small number of studies investigating HP physiology,
little performance focussed research is evident [2, 3, 7]. It is
possible that continued Winter Olympic participation will
prompt further research into the performance aspect of the sport.
KINEMATICS AND KINETICS OF THE HALFPIPE
For the purposes of this paper, three key components of
HP performance criteria are considered. Each component
may determine a riders’ scoring on the judging criteria
outlined above:
1. Rider amplitude - based on how far above the lip the
rider’s CoM travels,
2. Trick difficulty - depending on the number of
rotations and the addition of board grabs and other
aspects which will assist “Overall Impression”,
3. Successful landing - required for setting up
subsequent tricks and preventing injury [4, 8].
Fig. (4) provides a simplified breakdown of the
interaction of factors influencing trick success.
Rider Amplitude – “Boosting and Maximising Air Time”
Amplitude is important in itself as a judging criterion, but
also for th e ability to set up and execute tricks. Specifically,
for a rider to have time to perform multiple rotations with
control, their CoM must gain as much height above the lip as
possible. Air time can also be gained by travelling
horizontally down the pipe, however this sacrifices pipe
space and may reduce the number of hits the rider can
perform during a run. Several factors interact to assist and
create amplitude.
Board Control
Efficient board control from the moment of landing
determin es the rider’s ability to ride a line that optimises
velocity across the pipe into the CT maximising takeoff
velocity. Edge control and board trajectory are coordinated
by unique movements outside the body’s anatomical norm,
including: forceful ankle pronation and large valgus knee
angles for pressure and torsion on the board as well as
significant lumbar and thoracic spine flexion and rotation in
preparation for spins. The upper body provides gross
movement for trajectory changes and trick initiation.
The magnitude of the various upper and lower body joint
torques can differ considerably depending on where on the
wall (i.e. low or high on the ET) the athlete lands and their
position over the board on landing (i.e. toe side or heelside).
These differences may be particularly large when comparing
successfully completed tricks to ones that are missed,
particularly if such a trick results in a crash.
Amplitude
Measures the height of the maneuvers. Amplitude is the distance measured from the lip of the pipe to the rider’s center of
mass. The amplitude score is derived from the sum of all hits, divided by the number of hits taken.
Standard Airs (SA)
These include all airs or tricks that are less than 360 degrees. The basic kinds of standard airs all grouped into one of the
following: straight airs, air to fakie/fakie to forward, alley oop airs, straight switchstance airs, 180 handplants and liptricks
less than 360 degrees.
Rotations - Flat Spins (FS)
These are all maneuvers that include a rotation of 360 degrees or more in a horizontal rotational plane (flat spins) including
the rotations (360, 540, 720, 900, 1080,1260 and 1440).
Rotations – Inverts (IN)
These are all maneuvers that include rotation of 360 degrees or more in a horizontal plane and over 180 degrees in the
vertical plane in which the board breaks the vertical axis.
Overall Impression
The OI judges evaluate all phases of all the tricks. The judges will score the run by evaluating the run’s overall precision,
which includes the execution of the run, and the routine attempted no matter how the run is setup in its formation.
Fig. (3). Judging Criteria for Snowboard Halfpipe [6].
4 The Open Sports Medicine Journal, 2011, Volume 5 Turnbull et al.
Fig. (4). Diagrammatic Representation of factors influencing performance in Snowboard Halfpipe.
Timing: Point of
Take off, Point of
Boost
Waxing and board
dynamics
Joint Stiffness
Antero- Lateral Hip
Boost
Board Control to
ensure optimal line
across Flat
Take off Velocity
Maximal Amplitude Trick Difficulty
Trick Succes
Successful Landing
Position on
Eccentric Transition
of Landing
Number of
Rotations
angular Moment at
Moment of Take off
Rotational Inertia
Axis and Plane of
Rotation
Joint Stiffness
Rotational Inertia
on Landing
Maintenance of
Ground Peaction
Forces
Strength and Co nditioning Considerations for Elite Snowboard Half Pipe The Open Sports Medicine Journal, 2011, Volume 5 5
Resisting Centripetal Force: Maintaining and Creating
Horizontal Velocity
Like other jumping sport, HP rider amplitude (i.e. jump
height) is determined by the vertical velocity of the CoM at
take off, which dependant on the horizontal in-run velocity,
which in turn is affected by an efficient landing [8-11]. To
maximize horizon tal in-run velocity, riders aim to “stomp”
their landings. “Stomping” entails minimising the absorption
forces on landing by remaining stiff and immediately
pushing down into the snow upon impact in order to increase
the velocity on impact. To increase propulsive forces into
and out of the ET the rider will “pump” the snow similar to a
BMX rider [4, 12]. “Pumping” involves forceful lower limb
extension when ground reaction forces (GRF) increase as the
rider exits the ET onto the flat, thus applying pressure into
the snow, allowing the force normal to the snow to cause
more horizontal velocity.
“Boost” and Take Off – Supplementing Horizontal
Velocity
To assist vertical velocity of the CoM at takeoff, rather
than the vertical thrust of skaters, and other jumping sports
such as basketball or volleyball, HP riders rotate their hips
and knees forward towards the front of the board [4, 7].
From this position, anterior-lateral hip “boost” (a high
impulse rear leg and hip extension toward the front of the
board) and simultaneous lateral-vertical arm thrust (upwards
and toward the front of the board) assist horizontal velocity
(Note: horizon tal v elocity relates to velocity in the sagital or
“cartwheel” anatomical plane) [8, 13]. At the moment of
takeoff, hip and arm movement is quickly ceased to combine
the momentum of these segments with that of the rest of the
rider and board [8]. This “boost” also allows the rider to
align their CoM over the centre of the board which
maximises the vertical component of their velocity, provides
an axis to assist rotation and h elps prepare the rider for
landing [7]. If the rider extends vertically they risk
propelling themselves too far into the pipe away from the
ET, resulting in significantly greater GRF and increased
injury risk. Impact force and landing position is discussed
below.
Trick Difficulty – Optimising Angular Momentum
Successful high scoring tricks must be set up, executed
and landed with control. Furthermore as part of the judging
criteria relating to “Overall Impression”, tricks must be
original and seen to be clean and effortless without obvious
precursory movement [6].
While overt biomechanical wind up and expression of
effort is shunned by the culture and judging criteria, there
needs to be some precursory movement to assist rotation [6].
Across the transitions and flat, the arms may be kept wide,
increasing the moment of inertia to assist balance. To initiate
spins, the rider will reduce their rotational inertia through a
“wind up”, as they enter the CT, forcefully rotating the arms
from the wide position toward the CoM and the direction of
desired rotation [8].
Once the athlete is in the air, their trajectory is pre-
determined as their angular momentum is conserved
considering the only external forces on the system act at the
CoM, resulting in no external torques. The athlete therefore
must alter the distribution of their body mass around the
CoM to initiate specific rotational tricks. Rotational inertia
may be reduced: by retracting arms toward the CoM for
spinning (pirouette movement plane); by tucking the legs up,
or crunching head and shoulders down for backward and
forward flips (somersault movement plane), respectively.
Combinations of spin and flip producing movements will
produce high scoring off-axis tricks, but still involve the
same biomechanical principles.
Approaching landing, the rider may increase their
rotational inertia by “checking-out” or spreading the arms
outward from the axis of rotation in order to maintain a
linear path just as a gymnast does when dismounting [8]. As
well as checking-out, upon landing a rider may increase the
GRF and horizontal velocity by thrusting their arms
downwards through the transition. This has a similar effect
as pumping, or stomping in that it increases effective
horizontal velocity.
Successful Landing - Sticking it
In HP, as with many grav ity assisted sports, the
significance of error and the risk of injury is most severe on
landing [7]. Considering potential energy equals the product
of mass, gravity and height, the greater the height of a
previous trick the greater the PE which in turn will be
converted to KE (mass x velocity2) on landing [14-16].
Maximising impact is not desirable for the rider per se, but is
required to ensure maximal kinetic energy and resultant
velocity when landing on sloped surfaces [15].
Considering the presence of the slope reduces the normal
forces on landing, the impact the rider experiences is the
force it takes to change the slope of their flight path to that o f
the HP ET wall and fall line [11, 15]. These forces are
dependent on: the amount of absorption in the legs on
landing; how compact the snow is; angle of the ET wall and
fall line (which is dependent on the position on landing); and
horizontal velocity (relative to gravity and the fall line) of
the rider prior to impact [11, 15, 17].
The velocity vectors of landing on a sloped surface are
outlined in Fig. (5). Considering the rider will generally be
falling relatively vertically, the rider must land as high up on
the ET, towards the vertical as possible with high joint
stiffness. Reducing the stiffness of the landing [from high
(vector 1) to low (vector 3)] will reduce the velocity at
landing and hence increase the difference in Velocity vector
Vc-b. The smallest reduction in velocity (and consequently
the least amount of impact felt by the rider) will occur where
the rider’s trajectory is as close as possible to that of the
slope (as shown in vector 1, Fig. 5) when contact with the
ET is made. In this situation the rider aims to “stomp” their
landing increasing the impact velocity. Since the impact
velocity trajectory and the slope angle are similar the stomp
acts like a pump, increasing the rider’s kinetic energy and
hence speed in to the next trick.
Optimal Landing Positions – Maxima l Kinetic Energy but
Minimal Mechanical Stress
Ideally, landing patterns for snowboard should closely
resemble those observed during gymnastics “spiking” where
the absorption of impact through large joint flexion must be
constrained through well-timed joint stiffening to allow soft
6 The Open Sports Medicine Journal, 2011, Volume 5 Turnbull et al.
tissue dissipation of forces [18]. An optimal landing will be
high on the ET wall and involve high degrees of muscle
stiffness to ensure maximum gravitational potential energy is
converted to kinetic energy (velocity) of the rider.
Currently, there appears to be no peer-reviewed research
which has reported the GRF inherent to landing from the HP.
However, investigation into skateboard kinetics identifies a
load of 4-5 times body weight (BW) from a skateboard Ollie
height of less than 0.5m [7]. Although the impact and
absorption of snow and the angles and surface of the fall line
and ET differ from the hard, flat concrete of skateboarding,
HP riders often attain amplitudes of more than several
metres above the lip, so that if landing some distance from
the lip, they may fall a distance in excess of 3 metres. This
may suggest that at least in landings that aren’t high on the
ET, HP riders may need the ability to tolerate very large
GRF if they are to perform well and remain injury-free.
According to the impulse-momentum relationship,
impulse needs to be created to change the momentum of the
system. As the athlete has very high momentum on landing
and has little time to dissipate GRFs, the athlete must
produce high degrees of force very rapidly. The short
contraction times required for a stiff landing will require a
significant proportion of the rider’s maximum voluntary
contraction (MVC) force [9, 19, 20]. Further the stiffness of
the system and the ability of the r ider to tolerate the loading
and landing positions are dependent on the skeletal posture
and biomechanical alignment on landing. If the rider is
aligned correctly over the board and hip, knee and ankle
angles are at optimum force generating positions the rider
will be able to withstand much greater forces and also
produce much greater pump in order to gain speed through
the ET.
Considering th ese factors, incorporating awareness of
correct biomechanical position within specific strength
training for HP athletes would appear essential to
performance and injury prevention.
To assist in achieving substantial levels of muscle
activity and isometric force which are required for gaining
joint stiffness, HP riders, like skateboarders, should aim to
pre-activate the lower limb musculature prior to ground
contact [7]. Further increases in GRF can be developed by
the athlete pumping their arm downwards and forward as
they ride through the ET in order to transfer remote
momentum from their limbs to that of their total body
momentum and add to their horizontal linear velocity.
Body Position, Joint Angles and Velocities and Muscle
Activity
Snowboarding and skiing are commonly mistakenly
identified as “explosive” sports, which explains why
coaches/trainers have put much time into training fast
concentric movements in the past [21, 22]. However, in
order to prescribe more specific training to these athletes,
strength and conditioners need to have a good understanding
of factors such as the body posture, joint angles and
velocities, muscle activation patterns etc inherent to the HP.
Berg et al. [23] and Berg and Eiken [24] have investigated
how such characteristics may differ between the four ski
disciplines. They found eccentric action was the prevalent
muscle contractive force during ski racing [23, 24]. A
number of these variables are summarized in Table 1.
Much of what is currently known regarding the
biomechanics of skiing may be applied to snowboarding
considering they are both gravity assisted and share similar
snow surface and carving/turning mechanics. From initial
observation, the joint angles and angular velocities
associated with HP during the landing and trick initiation
may be more in the range found for freestyle mogul skiing.
However the duty cycle (time between turns/tricks) may be
more in the range of Super Giant-Slalom skiing, considering
the time to cross from ET to CT [24, 25]. Thus, we have a
Fig. (5). Diagrammatical representation of Halfpipe landing. Point B is the riders’ landing point while Line A-B is the flight path of the
incoming rider, and Point C is the distance from the lip into the pipe. Angle is the angle of the rider’s approach relative to the slope. The
resultant reduction in velocity (identified by Line Vc-b) is the difference between the rider’s trajecto ry velocity and their velocity relative to
the slope angle. Vector 1 represents an optimal high slope angle landing where impact forces will be minimal and may need to be assisted
through “stomping” (forceful lower limb extension). Vector 2 and 3 represents progressively poor, flat landings and progressively near the
end of the ET and the beginning of the HP floor.
(1) (2) (3)
AC
Va-c
Va-b Vc-b
B
Vc-b
Vc-b
Va-c
AC
B
q
C
B
Vc-b
Vc-b
Va-c
q
q
Strength and Co nditioning Considerations for Elite Snowboard Half Pipe The Open Sports Medicine Journal, 2011, Volume 5 7
scenario where HP riders experience greater maximal force
and impulse on landing which are being held for a longer
time, relative to competitive ski racing. Clearly, both of these
factors need to be considered carefully when prescribing
physical conditioning programmes.
Considering the magnitude of impact loads that are
imposed on the HP rider (especially if the rider lands low on
the HP wall and experiences a flat landing), the rider needs
to distribute these forces across the musculoskeletal system
if the injury r isk to any particular anatomical structure is to
be minimized [16]. Upon landing from a skateboard Ollie,
electromyography studies reveal an oscillation in the activity
of many muscles used to counteract vertical ground reaction
forces, due to the rider adjusting their CoM vertically,
sagitally, and laterally over the board. Similar oscillations
are likely to occur in HP as the rider adjusts their CoM on
landing in response to board position, fall line and snow
surface features (such as holes, or bumps of hardened snow).
Minimizing the range of oscillation however, will allow
greater kinetic energy to be available to assist horizontal
velocity, but will require specific sequencing and intensity of
muscle activation in order to avoid significant shock loading
[14, 26].
CURRENT HALFPIPE TRAINING PRACTICES AND
THE ROLE OF SPORTS SCIENCE AND STRENGTH
AND CONDITIONING
The following section of this paper focuses on the
potential to improve performance and reduce injury risk in
the HP, as well as some of the challenges that may arise
when working with these athletes.
Citius, Altius, Fortius – The Need for Sports Science
Some coaches and many young riders are of the opinion
that the only way of becoming a better snowboarder is to
snowboard more [8]. While it may be argued that skill based
competition is best trained by actually doing the activity, the
need for “training to train” should be understood with
respect to the speed of skill development. For example,
while the high repetition work performed on snow may
eventually develop sufficient strength and neural control
required to successfully complete highly technical
maneuvers (e.g. 10’s and 12’s and inverted maneuvers),
spending the off-season building this strength through
progressive resistance training, the ability to spin via
trampolining and diving may allow more rapid developments
from the time spent on the slopes. Furthermore ensuring a
quality environment for learning must be taken into account.
If sufficient fitness is lacking to remain mentally and
neurally alert, decision making, reaction time and/or muscle
activation patterns may be compromised resulting in poor
adaptation and learning and potentially increased falls an d
injury risk.
Coaches and athletes must appreciate the physiological
stresses that the riders are under during normal performance,
and under injury precipitating mistakes [27, 28]. When they
do, they may more easily accept the proven training
methodologies of specificity, overload, and recovery. Using
knowledge of the forces and energy systems characterizing
HP, the sport scientist or strength and conditioning coach
will be better able to develop injury prevention strategies
and, develop talent identification programs and sport specific
fitness and technique assessments [27-31].
The Sporting Context
The technical nature of HP does mean that on-snow time
is paramount to trick development [28]. Northern
Hemisphere competition starts mid October, not ending until
mid April the next year. The Southern Hemisphere training
season may extend from June until October. Thus, limited
time exists for dedicated ‘off-snow’ physical training for
snowboarding. Consequently, training interventions must be
short and intensive to fit between on-snow seasons/camps
[30, 32]. More importantly during the competitive season,
training programs must be at a level that does not induce
significant fatigue but still allows physiological development
and does not impair the riders on-snow performance or
increase their risk of injury, both of which will ultimately
limit skill development and competitive performance [5].
The Riders…. Athletes (?)
As with any high level training method, a base level of
conditioning is needed for injury prevention and in order for
movement- and velocity-specific training to be effective [5,
19, 33]. Snowboarding and more specifically HP is currently
the realm of the young athlete, with many of the top riders in
their teens or early 20’s. As a result the athletes (and
coaches) we are dealing with often have limited physical
training history and training age. As a consequence of the
sporting culture and self expression ethos of board sports, the
athletes commonly have little inclination to do off-snow
training, and even less understanding of the performance
enhancing potential traditional training methodologies like
strength and conditioning and sports science in general may
have for their sport. Thus, an understanding and empathy of
the culture of snowboarding and typical HP rider age is
essential for sports scientists and conditioners who wish to
work with these athletes. Without this trust and
Table 1. (L-R = Time Period from the Start of the Left Footed Turn (where the Left Ski is the Downhill Ski) to the Start of the
Right Footed Turn. MVC = Maximum Voluntary Contraction, SL = Slalom, GS = Giant Slalom, SG = Super Giant
Slalom, FM = Freestyle Mogul)
Outside Load Bearing Knee Angles (o) Knee Angular Velocity (o.s-1) Movement (Duty) Cycle L-R (s) Lower Body %MVC
SL 98-111 69±11 1.6±0.2 74±33
GS 86-114 34±2 3.5±0.6 73±21
SG 83-96 ~17 ~4.1 -
FM 62-133 ~300 ~0.8 -
8 The Open Sports Medicine Journal, 2011, Volume 5 Turnbull et al.
understanding, much time and resources may be wasted by
both parties.
Critical Considerations for the Strength and Conditioner
in a skill Based sport
Performance Interventions
Due to its importance in performance and injury
prevention, the landing appears to be the component of
snowboarding which strength and conditioners may most
easily influence. However, to be of most use strength and
conditioners must eventually consider the sport from start
(drop-in) to finish (last trick). Interventions must direct
training methods to facilitate optimal landings which, from a
performance aspect, will allow the rider maximum chance of
setting up their next trick, but also from an injury prevention
perspective, will ensure the rider is robust enough to cope
with the eccentric ground reaction forces and joint torques
encountered during less than optimal landings [18].
Maximising Amplitude
On landing the rider aims to land on the uphill edge and
sustain a position which will allow them to carve across and
down the pipe to gain speed while maintaining balance.
Strength and conditioning for creating joint stiffness and
minimising braking forces and range of motion at the knee,
hip and trunk in HP must also align with developing high-
intensity muscular endurance, balance and stability in low
sustained and rotated postures. Berg and Eiken [24] found
slalom skiers endured 75% MVC for duty cycle times of
around 2 seconds during racing (Table 1). It is not
unreasonable to suggest that HP riders would exhibit a
greater range of maximum and minimum intensities over a
longer duty cycle, given the GRF of the transitions, and the
unloading which may occur through the Flat. Like figure
skating and skateboarding, riders may ride, takeoff and/or
land nose or tail first, and from either side (heelside or
toeside). All four movement directions must therefore be
considered by conditioners [4].
Using the impulse-momentum relationship, strength and
conditioning for increasing horizontal velocity after landing
should focus on the production of high levels of total body
impulse (force multiplied by time). The overall impulse
produced will reflect the angular and linear momentum of
the trunk as well as the remote segmental momentum of the
limbs, particularly the hip, knee and ankle joint moments
that are produced in rotated and adducted femoral positions.
Core strength is also needed to ensure that the transfer of
remote momentum from the limbs is not dissipated through
the trunk.
Trick Difficulty – Spins, and Inverts
Strength and conditioning for spins and inverts should
focus on similar aspects used for arm drive to assist
“boosting” from the pipe. As with arm movements, phasic
core strength muscles must be adept at high impulse trunk
rotation and extension to assist wind-up and connection on
takeoff. Connection refers to when the torso muscles stiffen
allowing the upper body and the lower body segments to
combine their momentum. This allows a smooth coordinated
body movement providing a clean form which can be easily
seen and judged. These muscles must provide high impulse
movements in all 3 planes of movement to account for
natural, switch, front-side and backside spins.
Tonic paraspinal core muscles must be sufficiently strong
to ensure the body segment positions required for
minimising rotational inertia can be sustained, while also
providing stability for board grabs which will gain higher
scores for basic tricks. Tonic control of paraspinal muscles is
also critical on landing where maximal leg stiffness must not
be compromised by trunk collapse, and to ensure the forces
induced by joint stiffness are distributed evenly throughout
the active joints and not just the spine and pelvis.
Sticking It - Landing Safely and Conserving Momentum
Power and impulse are important variables in HP
performance as most actions must be fast and require high
forces over relatively short periods of time in order to
maintain momentum [34]. Unique to snow-sports which are
some of the few gravity assisted sports, is the dominance of
high load eccentric power associated with landing [24].
From a conditioning perspective the landing can be
likened to a stop jump or drop jump task; where horizontal
and vertical motion is rapidly reduced in order to change the
direction of movement [31]. Joint and ligament risk during
these tasks increases if muscle activation strategies (timing,
activation pattern and coordination of agonist, antagonist and
synergist) are not optimal and optimal biomechanical
alignment is not achieved [35]. This is especially relevant
when one considers the valgus and internally rotated
postures of the lower limb found in HP (as depicted in Fig.
6), and the potential for landing too low on the ET where the
magnitude of the GRF will be much greater.
In order to create the degree of stiffness required in high
force landing, the rider must recruit as many motor units as
possible from as many muscle groups as possible at the
correct time [36]. Maximal strength training provides a
means of recruiting as many fibres simultaneously as
possible, while eccentric power and drop jump training
(outlined below) could play a significant role in training
correct muscle activation timing and joint range patterns,
although more research is needed on the specific angles and
firing patterns found in HP riding.
Body Position, Joint Angles and Velocities
As discussed previously, in order to maximise GRF and
GPE conversion to kinetic energy and effective velocity on
landing, joint stiffness must be high and absorption through
knee bend and hip-spine flexion limited if landing high on
the ET. If a rider lands low however, they may need to
absorb more force through a greater range of motion in order
to reduce injury risk and regain balance. While the stance
depth may not alter the GRF's during concentric or eccentric
loading, the range and velocity of joint motion has a
significant effect on the forces under which the knee is
placed [31]. Joint stiffness incurs large angular velocity rates
over small ranges of motion. Smaller knee angles (i.e. lower
landing postures) do, however, relate to increased risk of
anterior cruciate ligament (ACL) injury through reduced
hamstring capacity, regardless of angular velocity. Thus
while landing with too much knee extension may result in
excessive compression forces, landing with too much knee
Strength and Co nditioning Considerations for Elite Snowboard Half Pipe The Open Sports Medicine Journal, 2011, Volume 5 9
flexion may increase the risk of non-contact ACL injuries
through ineffective hamstring contraction [31].
Conditioning exercises must therefore provide for a large
repertoire of joint angles, loads and velocities to ensure
riders are equipped to land safely in as many scenarios as
possible. Identifying the range of joint angles, velocities,
forces and torques involved in both poor and optimal
landings is important in developing plyometric exercises
which effectively simulate these landings.
Injury Prevention Interventions
Crash Robustness
Snowboarding has similar reported injury rates as skiing,
with 4 injuries per 1000 rider days [37]. Most snowboarding
injuries however, occur during jumping and landing impact,
rather than when falling and experiencing hip and knee
torsion during skiing [3, 22]. Snowboarding exhibits
significan tly more ankle than knee injuries, specifically,
anterior tibiofubular ligament strain and lateral talus
(snowboarders ankle) fracture, compared to skiing or
jumping sports such as volleyball or basketball [16, 37-39].
These ankle injury rates are greater in advanced relative to
novice riders due to the fact that when more advanced riders
fall, they typically do so from a greater amplitude. It has
been proposed that one reason for such a predominance of
ankle and impact injury in HP is due to the use of soft boots.
Because these boots are built for a high degree of
manoeuvrability in the HP, they provide limited support
from impact and twisting [38]. The development of new
boots that retain high levels of manoeuvrability but at the
same time provide greater support appears important in this
sport.
Shoulder dislocation and acromio-clavicular joint
separation appears to occur across all levels of rider [37, 39],
and are likely to be caused by blunt force trauma to this
region resulting from a fall. Associated with these types of
falls are wrist sprains and fractures, with novice rider s
tending to have a greater rate of wrist injuries than their
more advanced peers.
It is the author’s observation that snowboarders
commonly exhibit high degrees of flexibility around the
ankle joint in all planes of motion, with the ankle joint
tending to be everted. Such characteristics may assist them in
maintaining a feel for the snow and finding the internally
rotated and adducted hip positions required of turning and
take-off in the HP, however these postures are
biomechanically inefficient for withstanding large forces.
Strength and conditioning must focus on general robustness
to endure crashes, with specific focus on shoulder and ankle
joint strength. The rider must also retain the flexibility and
feel of the ankle and hip joint to create the ankle and hip
rotation required of fine board movements and trick
initiation and landing.
Joint strength entails both good soft tissue support
including muscle strength, ligament stability and muscle
activation patterns [17]. Deep abdominal core strength and
paraspinal muscle co-contraction is essential to tolerate the
spinal lo ads inherent to landing and in transferring forces
through the kinetic chain when preparing to perform a trick
[40]. While retaining sport specific movements, to ensure
biomechanical health the rider must be able to find and
maintain neutral spinal positions when required.
Seasonal Stamina
While a synopsis of the physiology of HP is beyond the
scope of this paper, the physiological load and the fatigue
developed through regular training through a season is a
critical consideration for conditioners. For example an
average training day may consist of 10-20 runs down and
hikes up the pipe taking place over 2-4 hours. This level of
riding may often be sustained for around 4-5 months during
the Northern Hemisphere competitions period.
Further, although the physiological load of an individual
HP run may not be great compared with other sports of
similar duration (30-60 seconds), sports scientists must
consider the temperature and altitude at which riders
compete and live. Riders should be able to sustain numerous
runs over several days, over months of competition, training
Fig. (6). Snowboard rider showing landing pattern typical of the ideal performance stance. Note the significant knee and ankle flexion and
internally rotated back knee.
10 The Open Sports Medicine Journal, 2011, Volume 5 Turnbull et al.
and travel. All this takes its toll physiologically and
psychologically, and as such must be considered in relation
to aerobic development maintenance and recovery
prescription to ensure that quality training occurs on snow.
Specific Considerations of the Sporting Environment
Off-Snow Resistance Training
With the exception of underweight athletes needing
increased gravitational potential energy, resistance training
protocols for HP riders must limit the hypertrophy response.
This is due to the potential for increased body mass to reduce
the vertical amplitude of the jumps and the ability to perform
air-borne rotations due to an increase in rotational inertia.
Furthermore, hypertrophy may speed the transition to slower
myosin heavy chain isoforms, reducing the power potential
of fast twitch fibres [10]. Increased body mass may also
disrupt the riders kinaesthetic awareness while
simultaneously placing greater stress on joints during
landings [20, 29]. Instead, resistance training methodologies
should focus more on neural adaptation such as motor unit
recruitment, synchronization of agonist and synergist
muscles, as well as eccentric modalities as discussed above
[19, 41, 42].
Skill aspects of riding, such as edge control, carving and
speed awareness, and the “gymnastic” proprioception in the
air requires many hours of practice to master. Trampoline,
springboard diving and mini-trampoline to airbed/foam-pit
are common training methods for trick development both in-
season and during off-season dry land training. These
methods are the closest riders can get to actual on-snow
training and offer a safer environment for developing new
and potentially dangerous tricks.
Combining sport specific movements with high load
resistance training, may assist in ter- and intra-muscular
coordination. This has been shown to allow the smoothness
and fluidity required of the skill activity to develop alongside
strength and power qualities [41]. The optimal timing of
these sport specific stimuli, post-activation potentiation or
“tuning” activities is yet to be determined. However so long
as loading (set/rep/rest) parameters excite but not excessively
fatigue the neuromuscular system they should not interfere
with the skill developing task [14]. These aspects should be
considered when incorporating strength and trick
development strategies such as trampoline and gymnastics
training within the same training phase and/or training
session.
When a given task is repeatedly performed, the central
nervous system learns to create a pattern from the afferent-
efferent transformations The conditioner therefore needs to
be mindful of negative transfer or the development of non-
specific and poor motor pattern in highly technical sports
like the HP and regularly obtain feedback from the athletes
and coaches to ensure that disruption of on-snow skills does
not occur. In highly skill based sports such as the HP, it has
been proposed that developing appropriate muscle activation
patterns, timing, proprioception and balance may be more
important than merely making the athlete stronger and more
powerful [12, 19, 34]. As a consequence, whilst being sport
specific is essential, athlete buy-in and understanding of the
rationale behind prescription is important to make use of
such specificity.
FUTURE RESEARCH DIRECTION
While there appears to be some literature on the HP
relating to kinetics and kinematics in the sagittal plane, there
is limited research into the frontal/lateral plane joint forces
and muscle activation patterns, or with respect to intentional
varus/valgus knee angles, and internal and external rotation
of the hip and trunk, found in HP [18, 31]. However, there is
even less data on the effectiveness or fatigue effects of
common HP cross-training approaches such as trampoline,
springboard diving, or mini-tramp training. Without specific
and comprehensive data on HP performance and potential
training strategies, developing and prescribing specific
exercises for improving HP performance and reducing injury
risk is severely limited.
The specific anthropometric, physiological, biomechanical
and motor control profile of the ‘ideal HP athlete’ also
requires quantitative investigation in order to assist
conditioning practice, talent identification, appropriate
fitness testing, and team selection criteria. As the sport
progresses and more nations conduct testing and training
interventions, more data will be available to create such
performance profiles.
SUMMARY AND CONCLUSIONS
Snowboard HP is a rapidly developing performance sport
for which very little scientific research has been performed
to date. HP is judged through the quality of tricks performed
during a run and the amplitude these tricks are performed at.
Trick success depends largely on amplitude - the higher an
athlete goes, the more time they will have for a trick to b e
executed. Amplitude is in turn dependant on the velocity of
the in-run, which is effected by the efficiency of the landing
of the previous trick.
Riders aim to minimize the potential for excessive impact
forces by attempting to land high on the pipe wall, whilst
ensuring significant joint stiffness to allow the potential
energy of the high landing to be transferred as much as
possible to horizontal velocity, rather than vertical impact
force. If in the undesirable circumstance of a flat landing low
in the transition, riders will need to use a large range of joint
motion and a significant proportion of their MVC force to
absorb the vertical ground reaction force which could lead to
injury and or a fall.
Sports scientists and conditioners could play an important
role in an injury prevention and performance enhancement
capacity within this sport through more thorough investi-
gation of kinetics and kinematics of HP riding. While the
sport scientist and conditioner needs to understand the injury
prevention and performance needs of snowboarding, they
should also be aware of age and sport cultural issues
regarding training motivation and history, and the physio-
logical and time demands of on-snow training commitments.
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Received: May 11, 2010 Revised: July 14, 2010 Accepted: November 22, 2010
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