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Mt. Diablo Challenge - October 5th, 2008
10.8m Race to the Summit, 3249 feet

October '08

The Mt. Diablo Challenge is a great Bay Area cycling event, and which takes place the first week of October.  The race starts at the base of the 3249 foot mountain which dominates the Bay Area skyline.  The views are spectacular.  Trivia note: only Mt. Kilimanjaro provides a longer distance viewing perspective than Mt. Diablo.

The park road is closed to traffic and after a bumpy initial couple of ups & downs, tilts upwards on smooth asphalt to the summit.  There is one brief downhill reprieve about halfway up the mountain, but which is countered with a cruel last 200 yards at a nasty 15% grade.  About a thousand riders participate each year and whose abilities and cycles run the gamut, ranging all the way to tandems, unicycles, and parents towing up their little ones.

The 2008 edition was my 3rd participation, but the first time that I was in reasonably good shape and I was thus looking forward to giving it a good go.
I used my tried and tested warm-up method where the drive to the race adrenaline rush that comes with wondering if you will miss the start jumps the heart rate and gets the blood flowing.  Unlike my previous participation, I arrived with about 4 minutes to spare - a perfect start.

A one-hour uphill time-trial is of course a great opportunity to get Power-tap data as to one's fitness, so I was pretty excited about the data collection opportunities.  I figured that a steady hard effort would yield between 310 and 320 watts and bring me up the mountain safely under one hour - it can be quite chilly at the mountaintop so the sub-1hr T-Shirt award had added incentive.

Equipment saw my tri-bike, a custom Guru with an 80 degree seat tube that most would consider a handicap, but which I am fine with.  I didn't bother with race wheels or such.  Clothing was short-sleeve jersey and shorts, carried a vest in the pocket for the descent.

I was in the 4th and final wave having signed up for the event on the last day - no big deal but it would mean a solo ride as the stronger riders started in the earlier waves.  I decided to run real-time power and not obsess with an average.

Ride Data Analysis

It is extremely useful to have objective, quantitative data to evaluate a ride performance.  Such data provides keen insight into the nature of your ride and how you might train and race more effectively.
Ride Duration : 56min17sec

Average Power (AP) : 308 watts
Normalized Power (NP) : 314 watts
Average Cadence : 88rpm (compact cranks - 50/34, 12-25)

Normalized Power/Average Power
NP/AP 1st 15min : 328/318 watts
NP/AP 2nd 15min : 307/303 watts
NP/AP 3rd 15min : 306/305 watts
NP/AP 11min – finish : 314/311 watts

Where I estimate my FT to be in the vicinity of 315-320watts, a 314watt effort for nearly an hour represents a hard effort.  On this day, I could not have gone much harder, but I was pleased to see that I could have continued at this pace for some time more, though I was quite happy not to.

Looking at the graph and data, the first 7 min show higher power - I knew that other riders would go out hard before settling in, so I did similar in the hope of latching onto a strong group.  As it turned out, there were only 5 guys in front of me and I decided that their pace was too fast.  Three of them would continue on, one croaked at about 15min, and another faded near the top.

Overall the pacing looks pretty good and which is important for a good time-trial performance. As I explained, I intentionally pushed the first 10min of the race, then settled into a very steady and even rhythm, pacing myself such that I could slightly increase the pace over the last 11 minutes of the climb.

As folks will have heard me say countless times in class, it always feels better to evenly or slightly build the pace than it does to hammer too hard in the beginning and then struggle the rest of the way to hang on.

In my experience, not having trained with a power-meter makes it almost impossible to evenly pace a time-trial effort for optimal performance.  Riders who first take to the roads with a power-meter are typically in for quite a surprise when it comes to pacing and how difficult it is to avoid pushing too hard in the beginning of a ride or interval effort.

Race Conclusions

• Training with the power-tap, both indoors and outdoors gives me keen and accurate insight as to my fitness and appropriate pace.
• Using the Power-tap to race helped me to pace well for optimal performance.
• The data download from the Power-tap is the most relevant performance testing – pretty silly the amount of money that people spend on laboratory testing that more often than not provides little insight into your fitness and ability to perform.
• The data provides me with a quantitative analysis of my fitness, and as such provides motivation to improve.

How to Go Faster next year

• I think the most improvement would come from starting in an earlier wave where I could benefit from both the company and draft of stronger riders.  As it was, my effort was a solo ride.
• I was pretty pleased with my fitness (FT 315-320watts) but I imagine that I can get another 10-15 watts improvement.
• Lose a couple of pounds.  Wattage/weight ratio especially important when climbing.
• Use lighter race wheels.

Power Training Terminology

FT – Functional Threshold
FT represents a rider’s maximum sustainable 1hr wattage average. For M2 Revolution riders, this would be about 95% of the benchmark we use in class.  M2 uses 315 watts as FT.

AP – Average Power
Average Power is self-explanatory – average watts for the entire ride duration, but given the often irregular effort in a cycling/tri event, AP often does not accurately reflect how hard the ride was in terms of its physiological cost.

NP – Normalized Power
Normalized power (NP) is a feature of a power analysis software program where an algorithm takes into account the variability of a rider’s efforts, and calculates a Power number that more accurately reflects the physical effort of a particular ride.

As an example of how AP and NP relate to each other and work effort, consider the example of a one hour uphill time-trial, and a criterium style race. In the TT, it is clear to see that the ride effort would be uninterrupted and largely even. In this example, you would get a clear idea of your best one hour watts - FT. Such an even effort would see NP and AP as very similar.

However, ride an intense one hour criterium and you will see that despite a maximum effort and feeling of such, your average power will be lower than your best 1hr watts (FT). This will be due to coasting through turns, dropping into the draft zone, etc. Thus, in this example, average power will not be as accurate a reflection of your work effort.

However, enter normalized power and its algorithm, and you see a wattage number very similar to your physical sense of effort – best 1hr watts – FT.

With the inherent variability of outdoor riding (downhills, turns, stop-signs, draft zones, etc.) Normalized Power and its relation to Functional Threshold (your best 1hr watts) becomes a very useful analysis tool because it gives you a better sense of the physical cost of the ride.