Is FTP the only metric worth chasing?

In a world of power meters and metric chasing, is FTP the only thing worth chasing?

With racing reduced, or not on the cards at the moment many of us are completing strong training sessions with a view to improving our FTP, but should we be doing this, or are there other areas of physiology we need to be looking at too?

In this blog we’ll be looking at the different metrics, why they’re important, and the next steps you can take to improve them.

What is FTP?
Functional threshold power (to give it its full name) is defined as the highest maximal power that can be produced in a quasi steady-state for a long time without fatigue. I know that’s a bit of a mouthful, but essentially this translates to the highest maximal power that can be sustained for about an hour, with a range of about 40 to 70-minutes depending upon a variety of factors.

Is FTP Important?
Yes, it accounts for the majority of the difference between riders, and as most cycling events are longer than about 90-seconds, much of the difference in ability between riders is due to differences in FTP.

What Other Metrics are There?
There are a variety of metrics that are similar to FTP (such as critical power), which are worked out slightly differently, and perhaps the differences here are beyond the scope of this blog. However, there are other metrics, which are of interest to us.

These include sprint power (sometimes termed Pmax, or neuromuscular power), anaerobic power (generally termed either W’ - pronounced double ewe prime, or FRC - functional reserve capacity), Maximal Aerobic Power (MAP), and Time to Exhaustion (TTE). There are others as well, but these are probably the main ones.

Power Duration Curve (PDC)
Most people intuitively know that you can go ‘all out’ and smash out a 5-second sprint, whereas if you’re completing a 200 mile ride you have to pace the ride at a much lower power output. This is summed up by the expression, ‘power is inversely related to duration’. Between those two extremes the power you can (maximally) maintain for any duration is defined by your power duration curve.

You can see an example PDC below (it’s mine!). What you may be able to ascertain is that on the left side of the graph, the red line which denotes my power, starts high and then drops away rapidly (to about 1-minute in), it then flattens out (to just under one hour - my FTP), and then drops away again (although, this is in part due to the fact that I don’t make any truly maximal efforts over a couple of hours duration.

Although the shape of the PDC is very similar amongst riders, the time durations where power drops off is dependent upon each rider’s own personal physiology.

Sprint Power (PMax, Neuromuscular Power)
This is the maximal power you can smash out in a sprint effort over a few seconds. Increasing this power is likely going to lead to you doing better in a finishing sprint of a road race, or, for example sprinting for the summit of a hill and beating someone (providing you’ve been able to stay with them up the hill).

FRC/W’
This is the amount of work (measured in Joules or Kjoules) that you can do above your FTP. It functions like a spare battery, where you draw down the energy you have stored there, either slowly if you say ride 5W above FTP, or very rapidly if you say sprint all out for 30-seconds. FRC/W’ recharges rapidly as you ease up but can still recharge even if you’re at FTP. Although it’s anaerobic energy it’s aerobic metabolism that recharges it. Have to put in a 30-second max effort to get to the top of a hill first — that’s your FRC/W’. Have to go absolutely flat out for 90-secs to cross to the leading break in a road race, that too is your FRC/W’

MAP
MAP is defined as the best 60-second power of an ever increasing ramp test. In a laboratory setting it’s used to measure VO2max (the maximal amount of oxygen you can utilise). However, if you just measure power, you’ll get an indication of FTP from your MAP, and also an estimate of your FRC/W’. This makes MAP very useful. Your MAP is an estimate of your VO2max power and if you’re say gunning for a 5-minute climb this will be a reasonable test of your MAP (and also your W’/FRC)

TTE
Time to exhaustion is the maximum amount of time you can sustain your FTP. Some riders can maintain their FTP for ~40ish minutes, while others can go as long as 70-minutes. Does this matter? Most likely yes, the longer you can sustain your FTP, the longer you should be able to sustain hard efforts that are longer than FTP. In effect, it’s a measure of your endurance. If your power drops off rapidly (i.e., your TTE is small) then most likely you’ll fatigue more rapidly than another rider with the same FTP as you whose TTE is greater than yours.

Improving all of these metrics (as opposed to just FTP) will help increase your ability at cycling. It’ll help make you a more rounded athlete and make you better at various types of cycling. In the next blog, I’ll go through some training sessions you can do that focus on improving the various metrics.

Our coaching and training plans take into account your individual physiology - your strengths, weaknesses, and areas for improvement in relation to what your ultimate goal(s) is. Your training will be different to others, and our coaching is as individual as you are, so that you become the best you possible.