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Sunday, August 16, 2015

Convict 100 km mountain bike race - yet another stage in my recovery

I knew that the attrition of age group sport from about 50 on was huge; but things are getting ridiculous now that I am in my 60's.  Its getting to be very lonely!  Read on....
The following is a brief pictorial of my latest venture, the gruelling Convict 100 mountain bike  (MTB) race.  The convict 100 is the NSW round of the Australian MTB marathon championships, attracting around 1500 riders, including the Australia's best open and age group riders.

I finished the 100km in 5hrs 4 min, just over an hour ahead of the next rider in my 60+ age category and over 2 hours ahead of 3rd place.  I was 63 rd overall.  To date, I have not lost an age group race in Australia.

There is also an analysis of what I did wrong and what can be done to do even better next time.  My goal is to be the 2016 60 years-plus MTB world champion.  I am back on track to achieve this lofty goal.

It was not long ago that I was lying on my back with what could have been a career-ending ankle injury.


Here's more about my ankle injury, if you are curious:

While I still have some trouble walking, things are on the improve daily and function is now about 90%.  Cycling is not a problem and I have even been riding A Grade Cyclocross races that involve some running on very rough terrain while carrying a bike and there are many unplanned dismounts!

Stripped off: Bug-Eyes is ready to get the show on the road!  I'm feeling very confident despite the distance and terrain to come.
Guess who is leading?  Old guys are supposed to be slow at getting going, so what's he doing in the lead!  I slowed shortly after, then seamlessly slotted into the peloton as it whirred past.  Off to the perfect start!

Coming into the finish, feeling really stuffed!  Missed out on breaking 5hrs for 100 km by just a couple of minutes - darn!


No, I did not fall off my bike but I worried I might once I stopped.  A few minutes of restful meditation and I was up and about.  The blood is not from falls during the race; they're from hitting saplings and bushes while hurtling along narrow, overgrown trails.

There was a 3rd placegetter but he was still out on the course, over 2 hrs behind me.  By the way, never once has it been announced by the MC that I am from New Zealand, while on the podium in Australia.  So I could not resist yelling "Go the All Blacks!"  Pity they lost.



What a nice brother Gordon is to hire a limo to chauffeur me all the way from Shellharbour to Sydney Airport.
This is one way to celebrate a victory.  Now where's the bubbly?


An analysis of how I rode the race

Here are a couple of graphs recorded during the race using my Suunto watch.

Heart rate: What you can see here is I peaked at 172 beats per minute early in the race.  I was working way too hard because I had my gearing wrong for the very steep climbs.  These peaks coincided with the first of the big hills and, later, some tricky technical and rocky climbs up sandstone terracing.  It was at about 2 1/2 hours that I began to tire and slow considerably.

Note, for later, that my average pulse for the race was 141 beats per minute for the 5 hours.
The graph above shows that my energy consumption steadily reduced as the race proceeded.
In the first half hour there was a very steep hill that had me almost at a standstill and then there was a river crossing.  Both can be seen as the "stops" on the graph above.  At about 2:40 I had to stop and take a toilet stop.  You'll note that from 3:30 through to 4:30, my pace up hills dropped right off as I struggled with the gearing set up on my bike.  The final sections of the race were pretty flat and this shows in the consistent pace.
This graphically shows even better how I tired quite steadily from about the halfway mark of the race.


Lessons from the race:

I could have gone quite a lot faster.

Take a full suspension bike

I took a light hardtail to Australia.  It is a rocket in a straight line but not suited for the very rough and rocky terrain of the Blue Mountains.  The constant pounding of the rocks wore me out and gave me a raw bum.  As much as studying Youtube videos of last year's race and writing to the organisers is helpful, it can never replace actually riding the course.  The fact is the course was much rougher than I thought it would be.  All future races will have a full suspension bike as the default pony.  I reckon the bike choice might have cost me a good ten minutes.

Be conservative with the bike gearing

I got the tyre selection perfect, along with tyre pressures - Yes!  However, I chose my gearing on the basis that the average speed was going to be a brisk 20 km per hour.  What I did not know was there were numerous short pinches, including stone terraces, that required the lowest gearing possible and I had the opposite!  This meant wasted energy, with strain on the legs and excessive heart rates, especially in the first half of the race that cost me dearly later. I lost a lot of time over the last 1/3 of the race as a result of having to work to hard up the hills earlier on.

Keep heart rate to 140 beats per minute

This means dropping back more within the field for the first half, having better gearing for hills and avoiding the temptation to keep with any over-the-top surges by others.  I think this means making about 150 beats the maximum for a race of that duration.  

In case you are wondering lack of energy intake and fluid were not factors.  I ate well and was hydrated (too hydrated actually!).

Get in more training kilometers or else choose shorter races

Gearing and bike selection aside: Its pretty obvious from the results that I am currently only fit enough to go hard for about 2-3 hours - not 5.  I think I will choose to do shorter races for the time-being.  I am too busy with other things to spend all day training.  The other factor, is the World Champs are July/August next year and I have yet to decide if I will contest the short course or marathon distances, or both.  There is little point in going hard out with big training with still a year to go.



Hey - no complaints at all really!  After all I won my category by a whopping hour-plus and this is after starting the year thinking my sporting days were well and truly over.


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