RSA is overrated?
Part 3
The study by Carling et al. “is the first to investigate in detail the characteristics
of repeated high-intensity movement activity patterns in professional soccer
match-play and demands specific to positional role” (p. 332).
I am posting the abstract here, while I am
pretty sure the full paper can be downloaded HERE.
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Carling C, Le Gall F, Dupont G. Analysis of repeated
high-intensity running performance in professional soccer. J Sports Sci. 2012;30(4):325-36.
The aims of this study were twofold: (1) to
characterize repeated high-intensity movement activity profiles of a
professional soccer team in official match-play; and (2) to inform and verify
the construct validity of tests commonly used to determine repeated-sprint ability
in soccer by investigating the relationship between the results from a test
of repeated-sprint ability and repeated high-intensity performance in
competition. High-intensity running performance (movement at velocities
>19.8 km · h(-1) for a minimum of 1 s duration) was measured in 20 players
using computerized time-motion analysis. Performance in 80 French League 1
matches was analysed. In addition, 12 of the 20 players performed a
repeated-sprint test on a non-motorized treadmill consisting of six consecutive
6 s sprints separated by 20 s passive recovery intervals. In all players,
most consecutive high-intensity actions in competition were performed after
recovery durations ≥61 s, recovery activity separating these efforts was
generally active in nature with the major part of this spent walking, and
players performed 1.1 ± 1.1 repeated high-intensity bouts (a minimum of three
consecutive high-intensity bouts with a mean recovery time ≤20 s separating
efforts) per game. Players reporting lowest performance decrements in the
repeated-sprint ability test performed more high-intensity actions
interspersed by short recovery times (≤20 s, P < 0.01 and ≤30 s, P <
0.05) compared with those with higher decrements. Across positional roles,
central-midfielders performed more high-intensity actions separated by short
recovery times (≤20 s) and spent a larger proportion of time running at
higher intensities during recovery periods, while fullbacks performed the
most repeated high-intensity bouts (statistical differences across positional
roles from P < 0.05 to P < 0.001). These findings have implications for
repeated high-intensity testing and physical conditioning regimens.
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As the abstract says, the aim of this study
is two-fold: (1) to characterize repeated high-intensity movement activity
profiles of a professional soccer team in official match-play; and (2) to
inform and verify the construct validity of tests commonly used to determine
repeated-sprint ability in soccer by investigating the relationship between the
results from a test of repeated-sprint ability and repeated high-intensity
performance in competition.
Without going too much in the study detail
(you can download it for free), what the authors tried to do is to get some
insights in the frequency of both HIA and RSS during the game. Again, I am not
going into details and positional difference. PLEASE NOTE
THAT I WILL MOSTLY DO COPY-PASTE OF KEY SENTENCES AND PARAGRAPHS FROM THIS
STUDY AND FINISH WITH MY CONCLUSIONS AND
OPINIONS.
They used AMISCO system and defined HIA and
RSS the way I defined them in the part 1 of this article. The authors then
proceeded to find out distribution and quality of recovery between HIA (zones: >61sec,
31-60sec, <30sec, <20sec), maximum number of HIA during the 1 min, 3 min
and 5 min window in the game, along with finding RSS patterns.
What they found is that the most commonly observed
recovery duration between consecutive high-intensity actions was >61 s
(67.0+9.6% of the total number of actions) with the average being 139 seconds. The
analysis of activity patterns in between consecutive high-intensity actions
showed that players across all positional roles spent the major part of
recovery in walking and jogging activities.
The highest number of high-intensity
actions recorded in any single 1 min (n = 5) and 5 min (n = 11) period was
observed in a fullback, and in a 3 min period (n = 7) jointly in a fullback and
a central-midfielder.
Across
all players, an average of 1.1+1.1 exercise bouts that met the criteria for
repeated high-intensity activity (RSS) were performed per player per match with
a statistical difference observed between positional roles.
The maximum number of repeated
high-intensity bouts observed in any one match was six (in a wide midfielder) and
the peak number of individual high intensity actions reported within any one
single bout of repeated high-intensity activity was seven (in a centre-forward).
The following picture presents a
graphical representation containing quantitative and qualitative information on
this intense bout of activity. The overall duration of this bout was 111.0 s,
equating to one high-intensity action every 15.9 s. Maximum and minimum
recovery times between individual high-intensity actions within this bout were
9.5 s and 40.0 s, respectively. The mean duration and length of these
high-intensity actions was 3.1+0.8 s (range 2.1–4.7 s) and 18.4+4.8 m (range
12.1–27.4 m), respectively. The mean speed of actions was 25.0+-1.9 km /h, with
a peak speed of 28.2 km/h observed in the final effort of the bout. Of the
recovery activity between efforts, 69.1% was spent in walking, 22.3% in
jogging, and 10.8% in running activities respectively.
 |
| Taken from Carling C, Le Gall F, Dupont G. Analysis of repeated high-intensity running performance in professional soccer. J Sports Sci. 2012;30(4):325-36. |
No
significant decrements in the mean and maximum velocity of individual high-intensity actions performed during repeated
high-intensity bouts were observed irrespective of the number of consecutive efforts
(3, 4, 5, or 6) performed in each bout.
When it comes to laboratory repeated-sprint
ability, the study showed that the players ranked highest in the four scores of
non-motorized treadmill test (mean velocity, highest mean velocity, peak
velocity, performance decrement) generally
did not display better performance in any of the match activity
parameters. In contrast, a higher frequency of high-intensity actions with
recovery times <20 s and <30 s was observed in players assigned to the
group reporting the lowest percent performance decrement. Finally, no
significant correlations were observed between any of the scores obtained in
the repeated sprint ability test and measures of match-play performance.
In the discussion part of the article
authors made couple of very important statements.
The majority of consecutive high-intensity
actions (67.0%) observed in the present players were performed after a recovery
period >61 s. Although approximately one-fifth of consecutive high-intensity
actions performed were interspersed by short recovery durations (<30 s), the present results nevertheless suggest
that these players had sufficient time to completely recover
‘‘physiologically’’ from the majority of high intensity actions. A 120
s recovery period between short bouts of high-intensity activity has been shown
not to lead to a decrement in running performance. even when 15 sprints were
performed in succession (Balsom, Seger, Sjodin, & Ekblom, 1992). In addition,
the present players performed an average of 1.1 repeated high-intensity bouts
per match, with these comprising only three consecutive high-intensity actions.
This result is substantially lower than the 4.8 repeated sprint bouts per match
observed in international women’s soccer (Gabbett & Mulvey,2008). This
discrepancy may be explained by differences in respective methods employed to collect
movement data as manual coding techniques are known to lead to overestimations
in high intensity running performance. These discrepancies in definitions
across studies suggest a need for consensus to ensure standardization in the classification
of movement thresholds (according to speed and duration) for time–motion
analyses of professional soccer match-play.
Again, this is one of the limitations of
this study and all studies based on velocity-based time-motion analysis as
stated earlier since they underestimate high-power movement patterns.
Hopefully, we will soon see more and more studies based on combination of
acceleration/power and velocity.
One
of the most important conclusions of this study is 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. Alternatively, the prescription of
supplementary specific conditioning programmes to improve performance in the
present group of elit soccer players could be warranted. Analysis of the
maximum and mean running velocity of the individual efforts performed in repeated
high-intensity bouts showed in general that
players were able to maintain performance even when six high-intensity
actions were performed successively with
<20 s rest between runs. Analysis of data on mean and maximum velocity of
consecutive high-intensity actions demonstrated no significant changes between
the first and final effort across repeated high-intensity bouts. Overall, the present
results suggest that the players studied were able to reproduce performance
when called upon to perform sporadic but extreme sequences of high-intensity running in
match-play.
In the repeated-sprint ability treadmill
test, players who reported the lowest percent performance decrement reported a
greater frequency of high-intensity actions interspersed with recovery
times<20 s and <30 s in duration. This result suggests that those with a
greater resistance to fatigue in a treadmill test of repeated-sprint ability
are able to perform a greater frequency of high-intensity actions with short
rest intervals in competition. In contrast, no association was observed between
test scores and the percent of the overall distance run that was covered in
high intensity exercise or the frequency of high-intensity actions and recovery
time between efforts. On the whole,
these results might suggest a lack of empirical support for the construct
validity of the present and similar tests of repeated-sprint ability as
predictors of high-intensity match performance in professional soccer.
In summary, this study has provided an
insight into repeated high-intensity activity profiles and the extreme demands
of match-play in professional soccer. Results from this study may also cast
doubt on the relative importance of repeated high-intensity activity and
therefore the need for conditioning programmes in an attempt to improve the
general and/or position-specific ability of professional soccer players to
perform repeated high intensity work.
MY OPINIONS
I am more than thankful to the authors of
this study since it is the FIRST study to report this kind of data. I also hope
that they will not mind me doing a lot of COPY-PASTE activity.
As I have already covered in earlier
installments and I will repeat one more time, the main limitation of these kinds
of studies are velocity-based time-motion analysis. Thus the conclusions should
be taken with grain of salt until we get more data based on power and
acceleration as well. For more info on this please check THIS
and THIS
post.
Another limitation of this study is the
reporting of mean values, without any
insights how the data changes over
the season or over the duration of the game. Even the authors acknowledged this
limitation – “However, the possible occurrence of fatigue patterns in repeated
high-intensity performance as matches progressed (e.g. towards the end of
games) was not examined here and warrants inclusion in future research.” (page
333). They could also have reported how
the data correlates with the success of the team, besides doing the analysis of
the HIA in possession of the ball (attacking) or without-possession of the ball
(defending). Having some analysis of time-in-play vs. total time might also
give some data, but I doubt.
One interesting finding is that players
with lowest decrement score (better RSA – at least this indicator, see the
problems with it in Troubles
with RSA) performed higher frequency of HIA with <20sec and <30sec
recovery time. But, still we are dealing with mean data. The study might include correlation of more physical qualities (MAS,
Vmax, Agility, etc.) with game performance, along with analyzing game
performance across the short game periods to see any “fatigue” patterns.
To conclude, even if velocity-based
time-motion analysis is valid we might miss data with reporting only mean
(average) values. For example, what if the guys with better MAS showed less
decrement in HIA performance across the game, especially in the last
15-20minutes of the game? What if the teams that are ranked highest perform
lower amount of HIA (as it is showed in the research by Di Salvo et al.), but show higher HIA activity
during certain parts of the game, or show less decrement? This is the problem with mean data as I have
warned before. What we need are distributions of the data during the game, the
season, etc and the correlations of those with physical qualities and overall
performance of the team. Probably the conclusion would be along the lines of di
Salvo et al. that overall technical and tactical
effectiveness of the team rather than high levels of physical performance per
se are more important in determining success in soccer, yet they would be more informative than basic mean values.
Although I would love
to see definitive answer whether RST (repeat sprint training) is overrated,
with the studies we have up till now, even if it they pointing to the yes
answer, I am not confident in giving definitive conclusion, because we still
lack a bunch of data. One of the most important data we miss, besides all of
those I mentioned are LONGITUDINAL CHANGES . These studies should aim to answer the
following type of questions:
- If the better teams show less HIA than worse teams, will decreasing HIA improve the team performance and standing and what is the influence of tactical/strategical training on HIA during the game?
- Will changes in training programs (especially in-season) yield changes in physical qualities and will those qualities change game performance (HIA, RSS) and thus game outcomes and team standings?
This kind of questions and studies will
yield more data about the CAUSALITY.
For example, even if this study showed that players with lower decrement score
performed more HIA in the game, that doesn’t show causality and it doesn’t mean
that if you improve your decrement score you will improve HIA in the game (and
it is even questionable will this make your team better). As Mendez-Villanueva
and Martin Buchheit concluded this is “simply, more complex” (Eur J Appl Physiol. 2011
Sep;111(9):2387-9.) (I will come back to this letter to editor).
Unfortunately, things are not so linear or
mechanic as we would love them to be, or as some portrait them to be. Hell,
maybe having high MAS and/or improving it may yield no effects to your running (HIA)
in the game, but might give you better work capacity to survive long in-season
and training sessions (as we know playing one game is easy – the trick is having
the similar performance over the long season), making you injury-proof and at
high level of playing which in the end might result in better team performance.
We are forgetting about injuries and excessive need to perform crazy good year
round and survive the training loads by only concentrating on the single match
data. An article by John Orchard is fantastic read in this regard (click HERE).
The question is: are we seeing the forest for the trees (we need to see both
btw) – do we really know what KPIs (key performance indicators) are important for
long term success?
Anyway, I wanted to thank Dave Tenney on heads up for Carling
et al. paper along for the article by
John Orchard on injuries. Also, I want to thank Arthur Smith for his prompt responses in my research papers
queries. Thank you bro!
And if you think I am done, you are wrong.
We still need to cover the newest research by Martin Buchheit (hopefully he
will find time to do the interview as well), because as far as I know it is the
only one study using longitudinal design showing how the improvement of physical
qualities affect game performance (HIA, RSS, etc). I advise you to check these
two posters before I review the study (click HERE
for and HERE).
I will also cover some ideas for the training, but that wouldn’t be extensive
at all since I covered some of my thought in Troubles
with RSA and I promised Dan Baker to finish one article for JASC. Besides,
I want to talk about power testing/assessment – I don’t want to spend time on
Repeat Slow Ability as Carl Valle would say :)
Stay tuned… the rant ain’t over :)
