Saris PowerTap Disc Brake wheel

This year, Saris were able to help out with a few pieces of equipment through Paligap – the most interesting piece being the new PowerTap SL 2.4 Disc built by Cycleways onto a Stans NoTubes Olympic Rim with Sapim Race spokes which just so happens to talk wirelessly with my Garmin Edge 705. I have used power on the road bike for over a year now and have found it a great training tool – sometimes, I do admit to riding t o a number (which is good sometimes) but the advantages for training specificity, pacing and training/performance recording has been immeasurable. With all that in mind, I was always intrigued to see what the difference would be off-road versus on the road. With a few weeks of training and an offroad time trial on the wheel I can start making some initial observations.

Full built wheel including brake rotor and rim tape is 1,250 grams

Firstly, mountain bikings power profile is dramatically different from the road. Looking at a road power file, you see power rise and fall a lot, this is nothing in comparison to what you find on a mountain bike. The amount of time that you spend at Anaerobic power levels is astonishing with the time spent around Threshold power levels being dramatically lower (unless of course there are long steady climbs in the ride/race). My observation is that you are basically coasting (steep or technical descending), riding at endurance pace (fireroad descending) or are at VO2max/Anaerobic Power Zones (all climbs).

A muddy one

Throughout the winter I spent a great amount of time training for increased power at Threshold/Tempo and increasing the time I can spend at it – it works well for the road but the power requirements for off-road are quiet different and something that I will be altering my training for.

For instance, if you take two rides, one on the road and one off-road that you would consider equally hard on your body, the MTB ride would have a much lower average power, but with a lot higher peaks. Also, generating the same power off road is much more difficult than on a nice smooth road.

Secondly, the cadences at which the power is output is dramatically different. Road riding, unless very steep (and not enough gears available) you can basically decide the cadence you wish to ride at, again, it is so steady. In mountain biking, the cadences vary dramatically, with a large chunk of the high powered efforts at low cadences (50-70). I guess this is a lot of the out of the saddle steep climbs, but again, a thing that my road riding had not prepared myself for properly. On the road, I do train at the slower cadences, but not at that power level – my Anaerobic, VO2Max efforts tend to be at the 80-90 range.

So what am I changing, without going into too much detail, more high powered steep climbs (not necessarily technical, I seem to handle those well), more 3-5 minute climbs and, if you read anything about my Cyprus racing, more training in relation to fast starts – clearing lactate etc…

Race Winning Moves Drill...

Was out yesterday doing a new VO2Max type drill called the "Race winning move" from the Coggan/Hunter power training book.

Basically it is - hammer for 30 seconds (attack the group), settle into 3 minutes at threshold and then sprint the last 15 seconds. I was taking the initial 30 seconds and final 15 seconds a little easier then required but still makes an interesting drill.


In other news - Garmin and Saris (the makers of PowerTap) will be working together to allow the Edge 705 'listen' to the wireless powertap. Finally, I'll be able to unclutter my road handlebars. I'm also still waiting to pick up the disc brake compatible PowerTap for off road use. That should be really interesting - I would love to see my power files from an XC race. Currently with the Garmin and Ascent software I can break down my race and check my times on various sections of a race, descents/climbs see where I tire. With the power, it would be another dimension.

Hopefully I will get the report up for the Marathon race from last weekend tonight - this weekend it is Mountain Mayhem :) Busy busy busy...

Christmas 2007

So Christmas has come and gone – what did I get up to in the last two weeks. Firstly, just before Christmas I got my new training toy. A PowerTap SL – it's basically a powermeter that is built into the rear hub of your bicycles wheel and tells you how much power you are putting out. I've put in 9 rides on it so far and I'm fascinated with the resultant information. With my technical background and love for sports physiology in general, I had a nice few hours around Christmas figuring out what things meant. I now know what it's like to put out 380 Watts for 20 minutes (mostly pain) and to do a 1000Watt+ sprint (again, mostly pain). All very interesting but the thing that got me most was how variable the power you put out is... A little of puff of wind and you cruising at 250Watts has you up at 350Watts! Stand up out of the pedals and your putting out 500Watts. I guess it will teach me a lot about pacing myself. My handle bars are getting a bit cluttered though with my Garmin Edge and the PowerTap readout...

The readout from one of my Spins with 3 * 30 minute tempo sessions

The Gizmo itself

Busy handlebars

For 9 days around Christmas I decided to stay in Monaghan – it was great having the whole family around and there was never really a dull moment. It also made a cycling change as riding around Monaghan (undulating terrain – mostly flat though) is very different from the spins I usually do around the Wicklow Mountains. Mel and I then had a very quiet New Years Eve, followed by our now traditional hike on New Years Day somewhere in the Wicklow Mountains. This time we walked around Lough Bray in pretty crap (wet/muddy) conditions. Hot Chocolate in Enniskerry made up for the cold weather though :)

Eva and Orla on Christmas morning

Conditions looked good at the start of the hike

But they got pretty crappy by the end

There are a couple of pictures from Christmas here.