so
today in this short webinar i'm going to
discuss with you the research and
application of blood flow restriction
within elite sports
and my name is dr stephen patterson and
if you've got any queries
or any questions about this presentation
and you can contact me on social media
or you can get me by email on the screen
in front
so what is blood flow restriction well i
like to
split into three different applications
the first application is that of
resistance exercise with blood flow
restriction
and this involves partial restriction of
blood flow to the working muscles
with the prevention of that blood
returning back to the heart
and the pressures that are typically
used are between 40 to 80 percent of
an individual's limb occlusion pressure
with one hundred percent being the
minimum pressure that fully occludes all
blood flow
so by working between forty ninety
percent we're guaranteeing that some
blood flow is
going to the muscle
the loads that are used are generally
low approximately 20 to 30 percent of
your one repetition max
with no real added benefit of using
higher loads
secondly we can perform different forms
of endurance exercise
again with partial blood flow
restriction
the pressures used to gain are between
40 to 80 percent of them inclusive
pressure
with some movement towards the lower end
of that scale due to the longer duration
of effort
so for example we've seen some work in
the lab where
individuals aren't able to maintain
pressures of 70 to 80 percent limit
exclusive pressure
for a longer period of time and we have
to reduce those down to 40 to 60 percent
range
the intensity is often used the gain is
low so for example during walking
cycling rowing but the intensities are
below 50 percent of an individual's vo2
max
and we use that for either intervals or
continuous efforts
and this produces similar adaptations as
higher intensity exercise
and leads to import improvements within
for example performance of time trials
vo2 max and vascular adaptations
finally we can also use blood flow
restriction passively
this involves no exercise but the
pressures used are higher
and equal to about 100 percent of your
limb occlusal pressure
typically this involves short two to
five minute periods of
full restriction followed by similar
reperfusion periods
this method has been used again to
increase shoot exercise performance
and help recovery following strenuous
exercise
so how can we apply the flow restriction
to elite sport
well to date there's very little
research specifically in elite
populations
research that has been done has shown
that blood flow restriction adaptations
are similar to that of untrained or
recreational athletes so for example we
see increased strength
increased muscle mass improved sprint
performance etc
but despite the limited research in the
area we do know it is regularly applied
in lead sports settings
and with very good adaptations and
responses
so for the for the rest of this
presentation i'm going to sort of cover
a range of different applications of
blood flow restriction and
weight i think it can and know it is
currently being used within
elite sports settings
the sort of main area where it is used
and
it's being used well it's around the
idea of injury and rehabilitation
i'm not going to cover that in today's
presentation but that is being covered
in another
presentation for this series
other potential options are around the
idea of managing training load and
stress
allowing us to manage pain
allow us to acutely enhance performance
and finally allow us to improve recovery
following strenuous exercise
let's first of all think about this idea
of managing training stress and mood
blood flow restriction is most commonly
used for rehab when higher loads are not
tolerated
however there is potential to use this
mode of exercise to manage
total training load and stress and pose
following intense training periods
for example implementing blood flow
restriction during appropriate stages of
a periodized training plan
may help counter the potential negative
effects of high overall training loads
and these are normally brought about by
you know increased gym
look paste work multiple fixtures in the
wakes of fixture congestion
pitch space and conditioning etcetera
the ability improve to improve strength
and muscle
mass with minimal mechanical stress and
muscle damage
may therefore be useful for example
during extensive travel
or tournaments when equipment may also
be limited
indeed in a recent study out of denmark
has demonstrated how alternating
periods of blood flow restriction
training with heavy load training
leads to similar improvements in
strength
and in this case and maximum voluntary
contractions
and in comparison to heavy loads only
for six weeks
so in this case what we're seeing here
is a improvement in mvic
of between twelve and seven percent for
the the blood flow restriction
and heavy load combined grip as well as
the
heavy loop grip respectively
they also demonstrated that they were
able to increase
the cross-section area of type 2 fibers
in both groups also
so demonstrating that even though the
load reduced and on alternating weeks
of resistance exercise the adaptations
were exactly the same
so we can be confident that we can
reduce
training stress by reducing that
mechanical load
by um alternating between blood flow
restriction and heavy load training
whenever you feel there is a need to
deal with the deluded athlete
other opportunities include the ability
to perform periods of microdosing for
example
increasing the frequency of training for
a short period of time
due to the low load nature of blood flow
restriction and low mechanical stress it
can be applied
once or twice per day for a short period
to induce rapid gains
now the following study from nathan
demonstrated that
large changes in muscle mass following
23 sessions in just 19 days
here they demonstrated an increase in
muscle fiber cross-sectional area of up
to 38
in as little as eight days which was
maintained until the end of the study
and up to 10 days post training
this was supplemented with a 10 increase
in strength also
this work demonstrates that despite
training
lasting approximately three weeks
adaptations occurred after one week
so we know that we can apply this for a
very short period of time
to induce adaptations
thomas bjornsson and out of norway took
this premise and introduced two
one-week blocks of microdosing of blood
flow restriction training
for a group of national network
parlisters
and interestingly they find that this
led to an increase in isometric strength
in the blood flow restriction group
however front squat one repetition max
was better in the conventional strength
training group despite trends for
improvements with glutathione
restriction
the blood flow restriction group did
however increase the
cross-sectional area of the vastus
lateralis this was mainly
attributed to an increase in type 1
fiber cross-sectional area
now for elite athletes concerned with
impairing power and speed this may not
be advantageous
but it is likely due to the large muscle
mass and strength of this well-trained
population
before the study began so we have a
series of studies there which
demonstrate that we can we can microdose
we can increase frequency for short
periods of time
and induce adaptations within strength
and muscle mass so
from an athletic perspective we can
think about um certain periods of the
season
in season pre-season where we can
actually do short periods of microdesign
of potentially blood flow restriction
which will allow us to
and get those adaptations that we desire
another potential application is to
reduce either pre or
post training pain so what we do know is
that numerous athletes train and compete
with pain and niggles
and therefore managing training node and
exacerbation of pain is a complex issue
one way we can do this and currently
being employed in late sports settings
is
using blood flow restriction before or
after practice in games
so there are a number of studies which
have shown
that blood flow restriction can decrease
knee pain acutely and chronically
compared to normal heavy nodes
and more recently our group have tried
to explain the reasons why
now the following figures basically show
pressure plane threshold before five
minutes post and 24
hours after either low load exercise
blood flow restriction at both 40 and 80
percent of the limb occlusive pressure
and heavy load training
and they do this for the exercise leg in
the top left
the non exercise leg in the bottom left
and then
the biceps in the top right and the
trapezius
in the bottom right and briefly
what we demonstrated was all exercise
acutely improves pain sensitivity
in the exercise muscle as well as
remotely
in the opposing limb and the upper body
however this improvement in pain
sensitivity was only in those
and for the first five minutes post
exercise
however blood flow restriction
significantly improved pain sensitivity
for up to 24 hours
with both forty and eighty percent
emblem inclusive pressure
but the eighty percent of inclusive
pressure group had the greatest impact
so we know that we can actually get a
reduction in p in
um for at least 24 hours if we use
um blood flow restriction at 80 percent
then occlusal pressure
and the final method i will discuss with
you today
is that of passive blood flow
restriction now the schematic here in
the screen shows three different ways
that it can be useful
the first is muscle atrophy which i'm
not going to cover
but um the second two are to enhance
achieve performance
and also then for recovery
now one thing to make note of is it's
important to apply pressure
when using a device that can measure
them occlusive pressure
as seen in this figure under the
pictures on your right hand side
the body position of the individual
changes limit limitless pressure
thus this measurement should be used and
not arbitrary pressures
because a lot of the passive blood flow
restriction work
and the work of the scheming
precondition as it's also known
uses arbitrary pressures rather than
based off limitless pressure
in the next two slides i'm going to
focus mainly on this performance and
recovery aspect of training
so passive blood flow restriction is
also known as ischemic precondition or
ipc
and it's applied before or after
exercise
so in this case here you can see that
the red blocks represent five minute
periods of full occlusion
or a hundred percent limitless pressure
with five minutes of reperfusion applied
in between and this is all done before
exercise performance
now there is a multitude of research
in blood flow restriction or
passive blood flow restriction and
scheme of preconditioning research
which has shown it's a potential benefit
of this mood for
improving acute exercise performance
with the main improvements coming via
endurance or aerobic based exercise
however future research needs to
standardize pressures violent loser
pressure
as i mentioned they normally tend to use
arbitrary pressures or 220 millimeters
of mercury
and why that's a problem when we come to
working with athletes is that
we know that they tend to have much
larger
um muscle mass therefore 220
and millimeters of mercury which is
standardly used would not be enough
pressure to fully occlude every single
one
of those individuals and that probably
explains the
discrepancy that we see within the
research with regards to passive blood
flow restriction and ipc
performance research
the final mode of application is to
enhance recovery following strenuous
exercise
and the evidence points towards
application after exercise
in a similar fashion to ivc virtual for
example periods of ischemia and
reperfusion
so bev natal in the top um
figure there they were the first to
demonstrate this following strenuous
exercise which consisted of strength
training
and sprint training which is basically a
typical training session
for athletes more recently
our group has looked at this and mainly
following
muscle damage in this case we prevent we
performed 100 drop jumps
and and then applied the passive
and blood flow restriction to see if it
could enhance recovery
and essentially what we find was
there is an improvement or a faster
recovery of force production
in this case um by approximately 24
hours
and following passive blood flow
restriction as evidenced here by the
black squares
this also resulted in and much
lower and increases in creating kinase
levels
and again it started 24 hours and that
actually
never really increased in comparison to
the control group
and also um reduced pain
over the time period as well as measured
by official analog scale
so we were able to demonstrate that and
whenever we use this and this mode of
exercise
following and exercise we can actually
help reduce um
pain damage and improve recovery
overall following um the exercise itself
so in summary we can use blood flow
restriction
to manage training load and stress
potentially
um certain benefits during delude
periods
and during long distance travel when
equipment access is minimal
and during periods of things like
fixture congestion
it can also be used for short periods of
high frequency training or microdosing
to improve specific and required and
qualities
one thing to remember is that blood
restriction is whenever used and
applied we can do this relatively
quickly so
you know one exercise lasts between sort
of five and ten minutes and
that's normally enough um to give enough
of an adaptation
and depending on the exercise that's
chosen
so there's obviously some potential here
of using it frequently
and quickly we can also use it to reduce
pain
for niggles and to get players through
training and games
and again something just to consider is
that we potentially suggest that we use
higher pressure so 80 of them occlusal
pressure and this can normally last for
up to 24 hours
and there's also some evidence that we
can enhance acute performance with
passive blood flow restrictions can be
preconditioning
and and finally we also know that this
can possibly help with recovery
following strenuous exercise
so for example we may potentially be
able to use it
um immediately after training or even
letting the athletes take the cuffs home
with them or if we're in hotel rooms or
whatever
it allows us to apply in this recovery
modality while people are just sitting
at rest
finally for further guidance on how we
can apply blood flow restriction
and its safety and we've put together
the following article which is a
series of experts all over the world to
come together with some consensus of
how we can apply bfr and some of the
sort of programming guidelines with
regards to different the different
modalities that i've discussed today
thank you