About the author
Alan Couzens, MSc (Sports Science) is the team exercise physiologist & coach for Endurance Corner in Boulder, Colorado. He works
with a wide range of clientele from recreational to professional triathletes. His personal blog can be found at www.alancouzens.com
For further information on Alan’s services, or to contact Alan, please see www.endurancecorner.com
Volume vs Intensity
CTL (TSS/d) vs FTP (w/kg)
Each data point in the charts
below contains the average of all
session data for a given athlete
over a 4 week block of training
(i.e. ~90 sessions worth of data per
data point). These charts (and the
regression equations) are linked
to my database and will continue
to update real time as more files
are added (i.e. more & more blue
dots will keep popping up until the
chart becomes a sea of blue :-) so
check back to see how the model
changes as more data is added. But
what’s the data’s current stance on
the perennial volume vs intensity
debate? Let’s first look at the relationship between average training
intensity (I.F.) over the course of
a block and aerobic fitness (as
measured by Functional Threshold
Power)
Perhaps contrary to popular belief,
the mean Intensity Factor of the
training actually has a very weak
correlation with aerobic fitness
(FTP). You can see this in the very
round scatterplot and the low R2
number. Providing a certain I.F. is
reached (~0.6), we see high fitness
occurring at a range of intensities.
We see athletes with very high FTP
numbers training at relatively low
average I.F. numbers - athletes with
FTPs of 5w/kg accumulating training blocks in the 0.6-0.65 region.
Similarly we also see relatively
unfit athletes - folks with FTPs of
3w/kg accumulating blocks of very
intense training at or above an I.F.
of 0.8. While there may be a hint
of a positive relationship between
intensity and FTP it is certainly not
a strong one. Put another way, if
we were putting together a model
Intensity: I.F. vs FTP (w/kg)
”In this data set,
the vast majority
of athletes with
an FTP north of
4w/kg (i.e. 300W
for a 75kg athlete) were training
more than 60hrs
per month.”
that predicts an athlete’s FTP, the
mean intensity of their training
would only represent a very small
part. Bottom line: The data suggest
that ramping up the intensity is not
a reliable way to improve fitness,
especially if it results in a loss of
volume....
The relationship between the
simplest number of all - pure
volume (training hours per
month) and aerobic fitness
(FTP) is actually more reliable.
Most people who train a lot
tend to be very fit. Not an
earth shattering revelation
but a useful reminder in a
world full of ‘time-crunched’
training plans. If you really
want to have a high FTP, plain
old monthly volume isn’t a
bad place to start. In this
Volume: Monthly hours vs FTP (w/kg)
position than the athlete
who, while having the same
long term average load is the
proverbial ‘February rock star’
who achieves his peak load a
long way out from the ‘test’
date.
data set, the vast majority of
athletes with an FTP north
of 4w/kg (i.e. 300W for a
75kg athlete) were training
more than 60hrs per month.
This relationship between
increased monthly volume
and increased FTP, while still
only moderate, is significantly
stronger that the relationship
between fitness and training
intensity.
1. Consistency – CTL incorporates a longer time frame than
one month of training. Using
default constants, it represents training load over an
~5 month time frame. Unsurprisingly, this data suggests
than an athlete who strings
together ~5 months of solid
load is going to be fitter than
an athlete who puts in one
month of impressive volume.
However, the strongest, most
reliable correlate of FTP
comes in the form of Chronic
Training Load - with a near
linear relationship between
CTL & FTP at least up to a
CTL of ~150: CTL of 50 ~= FTP
of 3.5w/kg, 100 ~= 4.0, 150
~=4.5.
2. Season ‘pacing’ - CTL
exponentially weights the
load closest to the report
date. Therefore, it rewards
athletes who ‘pace’ their
season correctly & put down
their greatest training loads
close to their event. In other
words, not only does the data
suggest that an athlete with
3-5 months of solid training
is going to be fit but also
that the athlete who adopts a
progressive approach and has
his highest load in the month
preceding the FTP assessment
is going to be in a better
This builds on top of that
moderate relationship between monthly volume and
fitness that we saw above in
that it br ings in 2 additional
factors…
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MARCH 2016 · RACEMAKERS
So, there you have it, the data
suggests the surest route
to a higher level of aerobic
fitness is to raise that CTL.
Now you can sleep soundly,
both from the extra training
load that you’re doing :-) and
in the knowledge that all of
the small stuff really is small
stuff. There really are no
shortcuts or substitutes for a
well thought-out, long term
progression of your training
load.
#######
”There really are
no shortcuts or
substitutes for a
well thought-out,
long term progression of your
training load.”
Hopefully this data provides
some good real world context
to put some of the ‘methodology hype’ in perspective. Furthermore, I hope it
prompts you to begin ‘mining’
your own data for patterns
that add to our collective
understanding and enable
us to make better, objective,
evidence-based decisions as
coaches and athletes.
Train Smart,
AC
RACEMAKERS · MARCH 2016
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