Junk Miles

One of the nice things about a power meter is it's very good at telling you when you are wasting time on the bike.  By wasting time, I just mean not enough adaptation for either the time or the effort.  For instance, you are wasting the limited training time you have on miles that won't make you stronger.  Even worse, you are leaving enough residual fatigue in your legs that you don't recover from the previous workout and then can't do your "hard" workout the following day either.  I first read about this from Friel a few years ago, but like most self coached cyclists I didn't truly follow my own advice.  Most published coaches, as far as I can tell, refer to tempo or Z3 as the junk miles zone.  This is where I think it's an oversimplification for the sake of the reader.  Using the definition I gave above, there is nothing wrong with a 2-3 hour tempo ride if you make it hard enough.  Some people call the upper tempo training zones as Sweet Spot Training and as long as you are going hard enough for long enough it could be an appropriate training zone.  I'm not going to talk to SST here since there is plenty of good literature on that by the FasCat guys.

http://www.fascatcoaching.com/?site_id=1060&page_id=34778&id_sub=34778
http://www.fascatcoaching.com/?site_id=1060&page_id=34129&id_sub=34129

You can define and scope the definition of junk miles even further than this, though.  Depending on the build period you are on and when your A races are happening, a lot of miles that would otherwise be appropriate training become junk miles.  For instance, doing anaerobic work in November is worthless unless you are racing cross.  That's not to say you shouldn't do any intensity, but targeted VO2 work would be wasted 4 months from your first race of the season.  Same goes for endurance riding like Z2.  If you have 10 hours a week of training, Z2, even during base season, is a complete waste of time.  A lot of people will disagree with me, but I would argue that the mainstream coaching community is coming around to this realization as well.  If you have 10 hours a week and you want to raise your endurance, right high tempo steady state SST rides as much as you can.  You simply do not get enough fatigue from riding Z2 10 hours a week to maximize your time on the bike.  It's similar to the whole "fat burning zone" argument.  Sure, if you jog slow for an hour you will burn more fat proportionally to carbohydrates, however if you run really hard for an hour you will burn so many more calories that you will actual burn more fat too!  You can get endurance based adaptation without riding Z2 is the bottom line.

The reason I'm posting about this is because I can very accurately determine how many miles a week I ride that don't contribute to my intended fitness goals.  The power meter, combined with WKO+, allows a detailed analysis of your rides throughout a build period.  I'm riding many less hours this year but my junk mile ratio has gone down significantly.  Hopefully I can carry this through the whole season, but so far so good, less TSS per week, better fitness gains, and overall less fatigue and therefore less chance of burnout.  I think my biggest contributor to burnout was all the junk miles I spent commuting, thinking that the "intervals" I was doing were helping.  This whole premise actually fits in rather nicely with my previous post "Anatomy of a Failed Interval" in which I explain my philosophy for this season (that I borrowed) of using a failed workout as a barometer for the need for rest.  I'm sure I will be adapting this as the season progresses and my legs make up my mind for me.