Training by feel or by numbers?

I’ve spent the week without a power meter. Jittery rear braking drew my attention to some small cracks in the rear rim immediately taking it out of action. Whilst it was being repaired I had to take a step back, abandoning wattage and looking at heart rate and speed if I wanted numbers. Both were alien to me, I’ve vague notions of their relationship with power, but little concern for the details – they’ve never mattered. Over the week I became convinced I was working harder in the absence of power.

Without my Powertap I had no way to know how hard I was training, but it felt like more. Perceived exertion was higher, I might be tired or I might be training harder. Speed seemed high too, but that’s so dependent on conditions, it wasn’t a useful guide. I would never know and as I considered the potential to test the theory I realised I could never find out – were I to ride blind to power, but record it, then aware it was a test I might ride harder!

What interested me was that left to train by feel I worked harder. I’ve observed the phenomenon before; the occasions I’ve been without a power meter have felt the hardest. They’re often followed by strong riding when power is returned as I attempt to prove that I was indeed working more. This coming week in the Pyrenees is going to be interesting – I’ve already set new peak powers over the first two days!

There has recently been a lot of discussion of training by feel versus training to numbers. Many coaches and athletes expressing good arguments for both sides. Spending a week purely training to feel and noticing a difference to training with numbers made me consider my own approach.

I don’t see the need to divide into camps – those who prefer to train by feel and those who like to analyse data. I collect data, as much as I can, on the principle you can only make use of it if you have it. Whilst I collect that data I mostly train according to feel, choosing intensity and pace to suit the day. If I feel strong on the bike I’ll push, but If I feel flat I’ll abandon any plans to test myself. I’ll revisit the harder set another day when I’m better able to complete it.

But I download data from every workout, I log details and keep notes on how it felt. I plot Performance Management Charts and compare the development with previous seasons. In this respect I am analytical; everything is studied – work load and intensities assessed, compared and checked for progress. At times it may influence my plans, but mostly how I feel on a given day says a lot. Plans and performance goals are tweaked according to how I’m responding to the training so far.

Most weeks my goal is to perform certain sessions across the disciplines – long rides, threshold work, long runs, speed work in the pool. A variety of workouts focussed on differing areas of fitness. I have overall performance goals I’m working towards and I focus my attention on races as they approach, but mostly I look to the margins for improvement. When I couldn’t run I put my attention on cycling and helped to transform my abilities there.

Spending a week without power didn’t change the nature of my workouts, though it seemed to increase my effort. Each day I trained by feel and was then mildly frustrated not to be able to download data and quantify the work done. I was stuck with gross estimations based upon heart rate, but I trained and estimated and my methods remained the same.

There’s much to be gained on both sides – planning and looking at the details of how you train, but being adaptable and responsive to how you feel. The important thing is that you do train, you do put the work in – this is what makes the difference. Whether you go by feel like many or you record every second of every session doesn’t matter if the right work is being done.

Ironman Training Library

From nutrition to pacing - a collection of CoachCox blog posts focused specifically on Ironman training and racing.


  • James

    Interesting post Russ. I have been thinking about training by feel for a few weeks now, but haven’t made the leap yet. This post is especially relevant for me given that I have just purchased the Finis swimsense watch so I now have the ability to collect data on every single possible session! Have I gone too far? Like you, I prefer to collect as much data as possible, to have it available if required later on. But am I missing the opportunity to really tune into how I actually feel while training AND racing? I race by numbers and is this holding me back? This is especially so on the run where if I see I HR too high I tend to back off whether or not I feel good. While for IM races this is a good approach, I think the with my coming season of half-IM races I might have to take the leap. I guess a good compromise for training over the NZ winter could be to take the garmin/powertap etc with me but have the screen blanked out (or reading pointless metrics). I guess I am just thinking while writing, but I guess your post has inspired me to give it a go. Thanks!

  • Feel vs numbers is an interesting question. I’ve mixed both, though it always surprises me to see how I train differently if I can’t see the numbers. I may think I don’t let them dictate my pace, but the evidence suggests otherwise!

    I’ve got a FINIS Swimsense too and collect swim data along with the rest – in my opinion it’s good to collect the data and it has the potential to enhance the way I train. My aim in training is always to go with how I feel, to push according to what my body tells me. In the Pyrenees each week I approached each climb hard and didn’t worry about wattage, just go for it. I survived and set myself the odd PB in the process.

    I’m also thinking of throwing in the odd ‘blind’ session into my training. Hiding all the numbers and just seeing what happens.

    Like you I’m not sure of the benefits, if any, but I think it’ll be interesting to try.