RSA is overrated?
Part 4
I want to finish this article so I can go
to vacation with ‘clear head’, and spend my time eating gyros, swimming and
playing beach volleyball instead of thinking about RST/RSA/RSS.
I am afraid that this article got away from
sole RST/RSA/RSS discussion. The things I warned against, besides trying to
answer whether RST/RSA is overrated, are the following
- Watch out for the mean/average values – pay more attention to variability of the data, distributions, zones and how the data evolves over time
- Watch out for the velocity based time motion analysis (especially with absolute zones without relative ones) – pay more attention to acceleration and power expression, not only movement speed.
- Watch out for the linear/mechanical logic, especially deducted from the cross-sectional studies (whose conclusions were based on mentioned flaws) – pay more attention to longitudinal studies and complex systems logic
Regarding the first bullet-point, David
Tenney from Seattle Sounders recommended me a book Flaw
of Averages by Sam Savage worth checking. When I checked the author’s website, the
following picture popped out:
I just can’t agree more.
Another feedback I received lately was by
Martin Buchheit regarding intermittent critical power (iCP) concept. He
actually did a study on it (Int J Sports
Med. 2008 Apr;29(4):307-15),
which I forgot to reference. You can check it HERE. The conclusion was
that iCP is basically hopeless.
When it comes to velocity-based time motion
analysis, I already pointed out to the two posts, but I will repeat this one
more time and stop bitching on it for the rest of the article (please check THIS
and THIS
posts). Instead I will focus on the last
bullet-point: Watch out for the linear/mechanical logic.
The mentioned linear thinking can be depicted in the following way:
Let’s deal with the first link. Will RST
improve RSA? I’ve covered this problem in my Troubles
with RSA article, but I want to give you a heads up on the
article/commentary by Martin Buchheit in
Sports Med. 2012 Feb 1;42(2):169-72 (check it HERE). Basically, Martin
concluded the same think (but with more proof). Here are some of the sentences:
When I was chatting with Håkan Andersson we
touched upon this RST à RSA issue (click HERE
to read the interview with Håkan). His opinion was to take context/athletes
into account – soccer players (with couple of exceptions) are not even close to
high level sprinters, and thus training aimed for high level sprinters might
not be needed for soccer players. This included speed work with very long rest,
etc. So, RST might kill two birds with the same rock. I am not sure if I
completely agree with this – I am more in line with Martin Buchheit that
possible the combination of the methods might be the best option. I am not sure
if I touched upon this, but I am pretty sure I warned against blindly applying
training methods and planning/programming from power/endurance sports for mixed
sports in THIS
article. To keep the long story short, in
my mind the story of improving RSA goes like this:
Of course, this logic is valid only if
improvement in RSA is related to improvement in Game Performance (and if that
actually matter for the final outcome). I will come to this ‘flawed’ logic of
mine later.
When it comes to the logic that improving
RSA or any other physical preparedness quality will improve game performance,
most of our proof is based on the cross-sectional studies and correlations. In
the letter to the editors (Eur J Appl
Physiol. 2011 Sep;111(9):2387-9),
Martin Buchheit (yes, the hero of this
article) and Alberto Mendez-Villanueva were critiquing the series of studies on
YoYo test by a group of authors (Bradley et
al.) in which the concluded that YoYo was sensitive to predict
match-related physical performance in soccer. I won’t go in much detail here
(make sure to check the article HERE) besides quoting
the title (Physical Capacity-Match
Physical Performance relationship in soccer: simply, more complex) and the
following sentence:
...Thus, the fact that players occupying different positions have
similar physical capacities (i.e., Yo-Yo IE2 test) despite the marked
differences in match physical performances suggest that the game’s tactical
requirements rather than players’ physical capacity might be more important
in determining on-field players’ activity patterns
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Speaking from my own experience, we had GK
that covered more distance in YoYo Intermittent Recovery Test Level 1 than
couple of fullback and middle fielders.
Thus, it is hard (impossible?) to conclude
that players with better physical qualities (MAS, YoYo, etc) will perform
better physically (more HIA, RSS and even ball contacts, etc) in a game (without
taking game tactical constraints of the positions played into account), and it
is even harder (more impossible?) to conclude that improving physical qualities
will improve physical game performance, especially out from cross-sectional
data.
The first longitudinal study to measure
effects of improvement/decrements in physical capacities on game performance that
is going to be published in Int J Sports
Med is Repeated High-Speed Activities
during Youth Soccer Games in Relation to Changes in Maximal Sprinting and
Aerobic Speeds by Martin Buchheit, B. Simpson and A.
Mendez-Villanueva. You can read the slides
from the presentation at 3rd World Conference on Science and Soccer, Ghent,
Belgium HERE.
The advantages of this study is that it
compared improvements/decrement in MAS (Vam-Eval) and Vmax (MSS – Maximum
Sprinting Speed) on the occurrence and nature of repeated-sprint sequences, but
assessed in two ways: absolute
(defined as at least 1sec long and above
19 km/h with maximum of 60sec recovery)
[RHSS] and relative (defined
as at least 1sec long and above 61% of
individual MSS with maximum of 60sec
recovery) [RSS].
The disadvantages were that it involved
only MAS and MSS tests (no RSA), the long delay between sprints in RSS (longer
than the other studies, which used below 20sec), 1-Hz GPS unit and it involved
junior players (14.5 year old players). Anyway, even with that ‘flaws’ this
study is unique in it’s longitudinal study.
Also, improvements/decrements in MAS and MSS
were judged as greater or lower than ½ of coefficient of variation (CV) of each
test (which they assessed previously). This is great statistical method, along
with using Effect Sizes, which they did.
I won’t go into deep analysis of this
study, but I will copy-paste some of the interesting sentences:
...It was recently
highlighted in highly-trained young soccer players that the relationship
between on-fi eld running performance and physical capacities is essentially
position-dependent [ 7 , 30 , 31 ] . In fact, for some positions, the
magnitude of the correlations between match running performance and physical
capacities is very large (e. g., strikers), while for others, very low and
non-significant (e. g., centre-backs). This is probably related to the fact
that tactical duties associated with playing as a defender limit running
activities. In contrast, attacking players have more space and opportunity to
express and use their full physical potential
... We examined, in
highly-trained young soccer players, whether substantial changes in physical
capacities (i. e., MSS and estimated MAS) can impact repeated high-speed efforts
(i. e., the occurrence and nature of repeated high-speed and sprint
sequences) during international club matches. With data limited to 1-Hz GPS
analyses, the main results are as follows:
1) a substantial increase in either MSS or V
Vam-Eval was at least likely
associated with a greater RHSS occurrence, while the magnitude of this
increase was position-dependent,
2) a substantial increase in either MSS or V
Vam-Eval was likely associated with a
lower RSS occurrence during games, but for some playing positions only,
3) despite the limited
available data, substantial reductions in either MSS or V Vam-Eval were associated with maintained
or even small-to-moderate increases in the occurrence of both RHSS and RSS,
and finally
4) the effects of
substantial changes in physical capacities on the number of high-speed
efforts and sprints per RHSS and RSS were clearly position dependent.
...Not
surprisingly, the players who became substantially faster (+4 to +7 % in MSS)
and/or fitter (+7 to +13 % in VV am-Eval ) managed to
perform a greater number of runs above 19 km.h – 1 (i. e., RHSS)
during games (+5 to +44 %). Present
results are in
accordance with previous longitudinal studies, where well-trained young
soccer players [ 23 , 26] were shown to cover a greater distance at high
intensities after a short training period leading to improved physical
capacities. Taken together, these data show that, at least until a given
fitness level is attained [ 5 ] , improving both MSS and MAS is likely beneficial
for high intensity running performance. While there is obviously no direct
link between match running performance and success in soccer [ 11 ] , a
higher match running capacity might still enable more involvements with the
ball and increase scoring opportunities[ 19 , 23] . Whether an increase in
MSS can have a greater impact on the ability to repeat high-speed efforts
than an increased V Vam-Eval is not easy to
examine with present data and limited sample sizes. It is however worth
noting that the associated changes in game activity were of similar
magnitudes. In a recent study in 61 team sport players, both MSS and peak
incremental test speed were shown to be the strongest determinants of
repeated-sprint performance [ 6] ; MSS showed however larger association with
mean repeated-sprint time than peak incremental test speed. In this regard,
both MSS and V Vam-Eval can theoretically impact high-intensity,
intermittent
running
performance, but in different ways
...In accordance with our
initial hypothesis, these results show that changes in physical fitness and
match running performance are not necessarily matched, and that playing
positions can affect these relationships.
In other words, this suggests that the observed improvements in
running performance during games may be more related to tactical and
strategic factors than physical fitness per se .
This idea is further supported by the fact that the players displaying a
substantial decrement in V Vam-Eval performed more
RHSS per games (i. e., full-backs and centre-backs) Similarly, midfielders
showing a decrement in MSS managed to maintain their number of RHSS per game.
Since a majority of the other players became fitter and performed more
high-intensity running during the second series of games, we can hypothesize that the players showing impairments in
physical capacities had to increase their work rate during games to match
those of their teammates. This suggests that fitness level was an
unlikely limiting factor to their high-intensity match running activity.
… The older players, while
being fitter, performed less sprints and less RSS than their less fi t (and
younger) counterparts. Taken together, these data confirm that in relative
terms, the faster/fitter players perform less RSS than the slower/less fi t
players[ 31 ] and that repeated-sprint activity is more likely affected by
game technical/tactical demands rather than by physical fitness itself [ 31 ]
. In support of this, we also observed in the present study an increased occurrence of RSS in players presenting impairments
in physical capacities (e. g., +20 % of RSS despite a
substantial 2 %
decrease in MSS for midfielders). Because
of their reduced locomotor speeds, these players probably had to use a
greater proportion of their maximal sprinting capacity to match the running
demands of their teammates (which translated into a greater number of
individual ‘sprints’ as defined in the present study)
... It is however worth noting that, although poor
physical fitness might not directly limit match running performance (as
discussed above), it may increase relative match running demands [ 31 ] .
This can affect decision making, passing ability [ 36 ] or fatigue
development during the end of a game.
... To summarize, the
present data shows for the first time that the changes in RSS
occurrence are independent
of those in physical capacities, and that playing positions can affect these
relationships.
... To conclude, with data
limited to 1-Hz GPS analyses, the present results show that substantial
improvements in both maximal sprinting and aerobic speeds can be beneficial
to (absolute) high-intensity match running performance. However, changes in
match running performance did not necessarily match those in physical
capacities, i. e., the magnitude of the changes in match running activity was
likely lower than that of physical capacities. Additionally, players
displaying impairments in their physical capacities managed to maintain or
even increase their high-intensity match running activities, and the changes
in match running activity in relation to those in physical capacities
were position-dependent.
These results confirm that, at least for some positions, physical fitness
might not directly limit high- intensity match running performance. Game
tactical and strategic requirements can affect on-field players’ activity
patterns independently (at least partially) of players’ physical capacities [
7 , 28 , 31 , 33 ] . These results also emphasize our lack of understanding of
how “maximal physical fitness performance” influences on-field running
performance, and off er a cautionary tale of viewing the physical fitness –
match running performance relationship in soccer in a simplistic manner [ 28
] . Further study should now examine the optimal position-specific training
strategies and determine at which extent improvements in physical capacities
are still beneficial for match running performance [ 5 ] and, in turn,
overall match performance and match outcomes [ 19 ] .
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Things are “simply, more complex”.
And I will try to explain one more factor why I think they are even MORE
complex.
This study reported that players who showed
decreases in MSS/MAS (physical capacities) were able to maintain HRSS/RSS (even
improve amount RSS, which is based on MSS) and the authors hypothesized that
those players had to increase their work rate during games to match those of
their teammates. I wonder were these players more ‘fatigue’ after the game,
more sore, demanding more easy training in practices, missed more practices,
had more minor injuries?
This brings me to one concept that is along
the lines with Stephen Covey’s Production and Capacity to Produce:
To be effective, one must find
the proper balance between actually producing and improving one's capability
to produce. Covey illustrates this point with the
fable of the goose and the golden egg.
In the fable, a poor farmer's goose began laying a
solid gold egg every day, and the farmer soon became rich. He also became
greedy and figured that the goose must have many golden eggs within her. In
order to obtain all of the eggs immediately, he killed the goose. Upon
cutting it open he discovered that it was not full of golden eggs. The lesson
is that if one attempts to maximize immediate production with no regard to
the production capability, the capability will be lost. Effectiveness is a
function of both production and the capacity to produce.
Downloaded from HERE
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Even if we forget about the flaws of most
of the studies (velocity-based time motion, cross-study design, reporting mean
values, etc) can we conclude that something is insignificant and not worth
training for if there is no statistical significance to the game performance
and the final outcome?
In the mentioned study by DiSalvo et al. they showed that higher ranked
teams perform less HIA than lower ranked teams. In the study by Carling et al. they showed that RSS does not
occur so much in a game and they concluded “that the low frequency of repeated
high-intensity bouts observed in the present team suggests that this specific
fitness component (RSA) might not play as crucial a role in elite match
performance as commonly believed “. In the study by Buchheit et al. authors showed that the players
that showed significant decrease in MSS or MAS were able to maintain HRSS and
RSS activities in the game.
All those data suggest that RSA is
over-rated.
Let’s pretend for a minute that if the
future studies show that most physical qualities have low influence on physical
game performance and that physical game performance have low influence on final
game/season outcome? Would we then conclude that physical preparation training
is insignificant for the soccer? Be it RSA, MAS, MSS, COD and training aimed at
improving them?
I think we are missing one crucial aspect
here. We are focused on production, while really forgetting about capacity of
production. We want to kill the goose and take the golden eggs.
One thing that studies report (or not even
report) and we don’t actually pay attention to are subject drop-outs. Well, in
sport studies there are a lot of drop-outs and I would really love to see
meta-analysis study of drop-outs. Most of the drop-outs were because of illness
or injury (or club transfer). I would be more than interested in characteristic
(both physical and game performance ) of those drop-outs.
Another thing I would love to see in the
(future) studies is how these drop-outs (and injuries or just unavailability)
of the players influences the season outcomes (make sure to check John Orchard
article in Br J Sports Med 2009;43:963-965; full text available HERE, along with this ARTICLE)
My point here i, that we are forgetting player availability/durability
during the long season and grueling sessions.
Even if improving physical preparedness
(which one?) doesn’t improve game performance and final outcome is not related
to game performance, what it might improve is player availability/durability
and that might affect the season outcome to the higher degree than being able
to improve RSS in the game. Yet, I need a proof for this. Anyway, I warned
about “productivity~capacity of production” complementary pair.
Preparing for a single game is pretty easy,
but preparing for 10 months long season with 1-3 games played per week, with
regular practices and travel is way different story. Having a high work
capacity is of utmost importance. The work capacity is usually defined by VO2max
level or any other aerobic ability. Although might be related, work capacity is
way more - it is the ability to perform
and recover from frequent specific work/training/playing. Smart practices and
hard recovery is very important. In my mind work capacity is capacity of
production, and great players are those with stable high level of performance
over a long period of time. Even if their VO2max is low. I think
there are huge genetic influences on work capacity, besides training. Without
expanding this discussion to talent~practice complementary pair (make sure to
check What Makes Champions? in Br J
Sports Med. 2012 Jun;46(8):555-61
HERE; along with this ARTICLE that concluded:
“Psychology plays an important role in
training, competition, tolerance of pain and motivation. However, the role of
genetic variation in determining psychological state and responses remains
poorly understood; only recently have specific genes been implicated in
motivational behaviour and maintenance of exercise. Thyroid hormone receptors
exist within the brain and influence both neurogenesis and behaviour. With the
current state of knowledge, the field of genetic influences on sports
performance remains in its infancy, despite over a decade of research.”) I might say that you could have the greatest engine in the world, but if you have
lousy breaks and chassis you cannot
do much with such an engine. Some players are just prone to injuries and some
are very robust. How can we influence this with training is beyond me. And, no
I don’t think it has to do with the newest super-functional, vibrational,
unstable corrective exercise. This rather has to do with individualizing
training loads and implementing smart player rotation and recovery strategies.
My final point is that we are forgetting capacity of production (player
availability/durability) and more studies need to take this into equation.
The thing I also noticed is that there is a
fine line between de-training and under-recovering (over-training) during the
in-season. The common pattern is that players start to feel tired after the
games. The coach thinks they might be training too much, and that wise strategy
would be to decrease training load. They feel even more tired. He decrease load
even more in hope they will re-fresh. They feel even more tired. This is the
thing that were confusing me over time, a lot. Still is.
This might be related to finding by
Buchheit et al. that even the guys
that showed decrement in MAS/MSS were able to maintain RHSS and RSS, but that
might make them work harder (that’s why we need time-motion analysis based on relative
speeds/abilities). You decrease load, they de-train even more and the game
(even if they don’t show lowered HIA/RSS – they might even increase due the bad
tactics and technique due decrease practice
time and getting out of the groove)
makes them more tired. Then the coach decide that they are de-training and he
increases the load. Guess what? They are even more tired and sore. Their work
capacity was lowered and the new workloads take time to get used to. I’ve
noticed this situation numerous times and solving it is not easy. It reminds me
about the “sharpening the saw” principle by Stephen Covey.
Stephen Covey tells the story of a man who was
walking through a forest when he came across a frustrated lumberjack.
The lumberjack was trying to cut down a tree with
and was swearing and cursing as he laboured in vain.
“What’s the problem?” The man asked.
“My saw’s blunt and won’t cut the tree
properly.” The lumberjack responded.
“Why don’t you just sharpen it?”
“Because then I would have to stop sawing.” Said the lumberjack.
“But if you sharpened your saw, you could cut more
efficiently and effectively than before.”
“But I don’t have time to stop!” The lumberjack
retorted, getting more frustrated.
The man shook his head and kept on walking, leaving
the lumberjack to his pointless frustration.
Downloaded
from HERE
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The problem might have been arisen because the
coach wanted to peak for the long
season, or because he was unable to continue sharpening the saw and
individualizing workloads. Or maybe all of this is psychological and related to
the grinding the season and routine
trainings and training sessions/locations. This is still beyond me.
Anyway, I am getting outside of the scope
of this article. I want to finish and pack for the vacation. I am going to
leave you with more complex graph I am working on and that touches on most of
the things we were discussing here. Please note that this is work in progress.
Finally, this series are over and I can go
with clear and calm mind to vacation. I hope you have enjoyed and learned
something along the way. Watch the big picture
and continue sharpening the saw!
Heading to Zakynthos!!! |
great job Mladen....greetings from Thessaloniki...
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