Cycling Peaks
Software recently added an exciting new feature to their
latest
WKO+ build called the
Performance Manager Chart (PMC). So what is it all
about, why is it so exciting and why should you be paying
attention? ‘Cause if you want to get faster you should be paying
attention.
Training with a power meter gives you a
clear picture of what went on during a single ride or race. The
downloadable data, when analyzed with CyclingPeaks creates a
huge amount of information - average power, normalized power (Pn),
intensity factor (IF) and more. Andrew Coggan, Ph.D designed a
metric called Training Stress Score (TSS). CyclingPeaks will
calculate a TSS for individual workouts using ride data and your
current Functional Threshold (FT). TSS is a numeric measure of
training stress which is determined by how hard and how long you
were pedaling.
TSS = IF x IF x duration in hours x 100
IF = Pn/FT
A single ride TSS is like looking at a
single tree in a forest. You get a nice picture of that tree but
don’t know where it sits in the forest. The beauty of the PMC is
it tallies up TSS over time to give a bird’s eye view of the
forest – or your entire season. The PMC tallies up TSS data in
two categories, Chronic Training Load (CTL) and Acute Training
Load (ATL). CTL is an exponentially weighted average of TSS per
day with a 42 day time constant. Or in other words it takes into
account the last six weeks of training. ATL is the same but it
has a time constant of seven days, so considers only very recent
training.
CTL is a measure of fitness. A lot of
training over a long time gives a high CTL or high fitness
level. ATL is a measure of freshness. Following a big training
week ATL will be high and you will be tired. Conversely a low
volume week will produce a low ATL and you will be fresh or have
zippy legs.
The final key metric the PMC tracks is
Training Stress Balance (TSB)
TSB = CTL – ATL
TSB can be thought of as “form”. When you
are really fit (high CTL) and really fresh (low ATL), TSB will
be high. This is peak form and the type of scores you want to
have on your “A” race day.
The PMC can be used retroactively to look
at CTL, ATL and TSB scores during times you had personal best
performances and during times you thought you should have but
didn’t. It can be used for forward planning to target a specific
CTL, ATL and TSB known to put you in peak form and to time it to
land smack bang on race day. The PMC takes much of the guess
work out of training and peaking.
