Sunday club run - hardest day yet

Did the club run down to Thruxton yesterday. Weather wettish and windy plus a few hills. Ended up doing 80km or so. Run in took us up to Wash Common so peeled off just before home and did 5 runs up the lane that runs parallel to the Andover road. This is a 1 mile run that goes uphill at around 1-2% pretty much all the way. 5 intervals averaged from 266W to 324W each one increasing from the last. Pretty happy with this.

All in all ride set a new high for this season of 284TSS points.

MAP comparison - November to Han

I took a bit more of a detailed look at the 2 MAP tests I have done so far. The chart above shows the power and HR curves for the two tests (power curve is a rolling average of past 20 seconds power to keep curve smooth)

The power curves are pretty much identical up to around 270W, then they start to diverge with the November test being about 10W higher. The reason for this is I adjusted the power readout to average over 30secs for training and forgot to reduce.

More interestingly the HR curves are separate right through the test, with the January curve being consistently less than the November curve, consistent with my being able to keep going for longer. Conditions were pretty much the same in terms of temperature, so I put at least part of this down to my training.

That said very aware I need some more data before I can make any firm conclusions. Will continue to focus work on the zone 240W-280W over the next 4 weeks and retest again after then. Will be interesting to see if HR in this zone maintains its gap (or hopefully widens).

One variable I know I will change for the next test is not to display HR. I know my "max" is around 185 and think this may be a limiter as when I see the HR getting above 180 I think I must be near the end. (One other benefit I get from having a power meter. Getting power up is a motivator for me but seeing HR touch unknown zones makes me worried.)

Going for Gold?

Just taken a look at the Tour of Wessed details http://209.132.24.3/downloads/Information_manual1.pdf

The standards are pretty tough, which is probably as it should be. For me gold means
Day 1 148km 5:00 (avs 29.6kmh)
Day 2 166km 5:30 (avs 30.1kmh)
Day 3 171km 6:00 (avs 28.5 kmh)

The times are doable, I averaged 30.2 on the TOW day1 and 28.7 for the 188km Tour of the Black Mountains, but will leave little margin for error. The weather+riding single speed meant I only did 26kmh on TOW day 2 this year and this combination left me pooped for the final day when I averaged the same speed. Still I have more experience now and hopefully will be fitter this year than last. So overall glad the standards are so tough and prefer this to situation where I can get a gold when not even trying.

January MAP test

Did first MAP test of 2008. Felt a bit rough past couple of days, due I think to slightly overdoing the diet. So had a day off yesterday and did MAP this morning.

Felt pretty good and result very pleasing. Kept going for a minute more than Nov test and broke 400W with MAP of 401. Gives me a power/mass of 22.63 which is still "Good". Training zones in line with my training plan. Given I have not been doing any specific training in the higher zone 6 end hope that I can improve further. Time will tell...

Russel Brand - fails the exercise bike test

Slightly off topic, but not entirely. Started cycling as way to get fit and lose weight and remains key goal. Helped in this by having an indoor exercise bike + a small DVD/TV. So I often pedal along while watching a film/TV series.

One by product of this is that how good or otherwise the DVD is can be judged by how hard I am exercising. The better it the easier it is to pedal (e.g. now watching the Sopranos and for some episodes have been chugging along at a good tempo pace without even noticing.)

On the other hand if the show is rubbish I find pedalling harder. To date the worst thing I have seen was the film Alexander. However this was beaten yesterday when (at sons insistance because apparently I am the only person in the universe who does not find him funny) I watched a DVD of Russel Brand's live show. This was real hard work, despite choosing a very easy exercise program it was hard to keep concentrating. Fortunately the DVD skipped a bit which gave me the excuse to fast forward through long sections where all he did was moan about how he had been treated at some awards or other or read out bits of the Daily Star to his audience.

Opinion isnt changed. Don't like or dislike Russel Brand, he just isnt funny.

Marmotte - expanded

As result of earlier enquiry into multi day sportives (see earlier post) I found that there are a few more events taking place in Oisans at the time of the Marmotte.

These are
Vaujany Sportive (173km)
Grande Rousse (40km but 1600m climbing)
Grimpe Alpe (TT up Huez day after the Marmotte)


I have decided to do these as well. The Vaujany I will used as a f peak training ride plus it will be useful to get some experience of riding a mass sportive prior to the Marmotte.

The Rousse looks the sort of distance to do a final event week ride to keep me sharp and the final Grimpe should hopefully be just a bit of fun to round off the whole trip.

Result of all this is that I should be spending a couple of weeks in the Alps end June. Looking forward to it already..

Cereal Day

Despite my exploits on the bike over the weekend I still managed to put on a couple of pounds. This is a not unfamiliar situation, all of my long rides away have resulted in me coming back heavier than when I left.

Reason is that having slogged your guts out it feels only fair to fill them up again. At home my tendancy is to gaze longingly into the fridge with what Mrs M refers to as an "anteater" look, hoping to find some delicacy or other, usually involving cheese.

I have come to the conclusion I have little self control. So what I have started to do is have the occasional "cereal" day. This is pretty simple, on said days I will only eat bowls of cereal (the "good" ones like shredded wheat, weetabix etc.). I reckon these are about 200 cals a go with a reasonable balance of carbohdyrates/protein/fat/fibre, I allow myself one every couple of hours or so which I reckon ends up with me eating 2000cal or so on a day when I will just do some light recovery work.

Hopefully this will result in my shedding a few pounds before May.

Base vs Club ride

My two rides over the weekend showed what I think is the difference between a focussed base ride and a club ride. My base ride is below (smoothed to 5:00). The lines on the power graph show the start of my Endurance (157) Tempo (213) and Threshold(255) zones. Apart from the false start (my mudguards were playing up) and end warm down almost the whole ride is above the lowest endurance zone. (Even more would have been had I not needed a few map stops and avoided falling over in a ford..)

By contrast my Sunday club run shows a quite different picture. Here most of the effort is in the active recovery zone, with just a few spikes for climbs and the likes. While I felt tired at the end of the ride this was more of a rollover from the previous day than due to the ride itself and on Monday morning felt less tired than Sunday morning.

Hard old weekend

Had a hard old weekend of training. As an entre Friday evening did a max strength session, getting to target in terms of main exercise (single leg step ups 67kg). Then finished watching (and hugely enjoying) the last couple of episodes of the first Sopranos series.

Weather forecast for the weekend was constantly changing. So when I got up Saturday to see the sun shining I decided to have a ride out to Pewsey to recce the next club run I was due to lead. I did not go out with any special training plan in mind but feeling good aimed for an average 200W over the ride. Managed this comfortably averaging 210W(24oNP) for 3:45. Only downer (literally) was me falling over on a flooded road. My own fault, tryed to coast through to avoid getting too wet and ran out of momentum half way through.....

Sunday was forecast to be rain and wind. So I got well togged up for the club run, even to extent of using shower cap over helmet. This worked perfectly in making sure it did not rain at all. It was a bit windy and had to work a bit harder coming back than going out.

All in all did 9 hours over the weekend covering some 166km with 450TSS points. This resulted in my PMC CTL taking quite a hike upwards so will steady down a bit in week to come.

Multiday sportives/interesting tours.

Doing the Tour of Wessex again this year and also the Tour of Ireland. These are both multi-day sportives and thought it would be interesting to see if there are other multi-day events out there. After all if you take the trouble to go somewhere to ride a sportive why not do it for several days rather than just ride and come back.

So put a post up on Bike Radar and got some interesting replies.

Here is list to date. I have made a guess as to whether event is a sportive or tour (former meaning lots of riders, timed). All look very interesting and already thinking about 2009 and possible change of 2008 plans to do the Oisans event in July.

Sportives

UK 3 days Tour of Wessex - tourofwessex

UK 2 days Cycle Cairngorns cyclecairngorms

Ireland 4 days Tour of Ireland tourofireland

Italy 6 days Giro delle Dolomiti girodolomiti

Sardinia 7 days Giro Sardinia Giro Sardinia

France 4* days Trophee de L'Oisans bike-oisans (* 4 events spread over 7 days including the Marmotte)

France 2 days Cleremont-Aurillac ctmontferrand

Italy ? days ????? two events start August on this site but no details bicimilano

Tours

USA 7 days Ride the Rockies ridetherockies

USA 7 days Bike tour Colorado bicycletourcolorado

France 4 days Raid Pyreneen bikepyrenees

Italy Tour of Italy 33(!) days bike-dreams

Cardiac Drift - some more...

Found a useful secret in WKO (thanks to Joe Friel blog

http://www2.trainingbible.com/joesblog/2007/08/ironman-uk-power-graph.html

(see comments for instructions)

on how to get WKO to show a measure of cardiac drift. I went back to the cardiac drift test I did a bit earlier and is showed for 30 minutes at 200W my drift is 2.8%.

In other tests 30 mins at 230W showed a drift of 4.6% and 90 mins of varying 160-185W actually showed a negative 2.6% drift.

Interested in this new measure I went back to my time trials last year these showed

H10/3 10mile flat TT (first ever) 325W (NP 328) drift -1.39%

H10/3 10mile flat TT (second ever) 328W (NP331) drift 9.2%

These show in figures what happened in practice. First time out I took things conservatively going out then put power on coming back but still had a bit to spare.

Second time out I pushed too hard in the first half, averaging 337W(NP345) but got knackered. This shows in a drift of 13%. So had to peg back on return averaging only 317W.

H10/3A (rolling with headwind) 10 mile TT 324W(NP 331) drift 10.2% - again got pacing wrong as first ride on the course and did not leave enough for headwind coming back.

HC248 (hilly 24km TT) 304W(NP313) drift 4.6% - first time on an unfamiliar course, so took things conservatively

HCC247 (flattish 25mile TT) 280W(NP 284) drift 3.7% - first (so far only) 25 mile ride which I did at last minute. So again rode conservatively.

So overall interesting how drift measure ties up with how I rode. I guess one measure of fitness is being able to push up your power while keeping drift stable. Will be interesting to see what rides in 2008 will show.

Wi

Powertap flat battery frustration

NRC turbo session last night. Still doing 4 minute intervals on big ring from 7th rear cog down to smallest. Down to 2 and a half minutes rest.

Was planning to try doing these at 290-320W but my Powertap again refused to read the rear hub. Bizarre as was working fine Saturday.

Replacing the batteries sorted the problem out but could only do this once I returned home so no power data for session which is a smidge frustrating...

Training smorgasbord

Responded to a forum question yesterday asking how people dealt with training plans, where planned workout could not happen for one reason or other.

This was something I learned from last years experience. I found that trying to plan a given workout on a given day was both time consuming and pointless. More often than not I did not do the workout and sometimes even when I did some of the fun was taken out because it felt like going back to school.

So this year have adopted a smorgasbord approach. I have a range of workouts suited to the training phase I am in and pick and choose from that according to time, conditions and how I feel. I use WKO and its performance management chart to take care of ensuring my overall training load is on plan.

Today was good example. I had a day off so had planned a middle distance fixed "E3" ride. I got up to find that weather was combination of wind and rain and prospect of slogging round for a few hours outside had little appeal. So instead I stayed indoors and did a highish (for base) M1 session where I ramped up from 230W to 300W over 60 mins. The whole session including warm up/down came in at TSS 115 IF 0.847 (This compares to my last fixed ride that was 2:40 long, with a TSS of 106 and IF 0.647, showing loads comparable, albeit at different intensity )

I felt really good and strong doing the workout and overall am sure it did me more good than slavishly following a rigid plan.

Beware black ice

Bit of a downer on Sunday in more ways than one. Volunteered to share the load and lead some club runs. First was last Sunday and I did a recce ride of the route just before Xmas. (as here:
Ride

Snow was forecast for the week, but never materialised, so went to bed Saturday hoping it would not be wet. Woke up Sunday to lovely blue sky, so rode off with a happy heart to the club run start point, resplendent in purple stegasaurus helmet cover (Xmas pres, see SPAM photos).

Very good turnout, something like 15 or so. However a number of stories re icy roads with some saying they had already had a spill. I did not pay this too much heed until we started out. We had gone no more than 400m or so and a call came up someone had crashed. I was at the front so stopped, then turned to go back and see what had happened.

Or to be more accurate tried to turn, my front wheel went at a 90 degree angle to where it was meant to and I hit the road. This turned out to have a sheet of sheer ice right along it.

I was very surprised as I had cycled along said road earlier and noticed nothing. Think this is a case of ignorance being bliss as not expecting ice I had not noticed it.

Anyway unfortunately we had to change route plans and go via main roads. Nonetheless passed 2 accidents during the ride, in both of which cars had gone off the road. Strangely both were 4x4s.

So bit disappointed plans went awry. Still the route is in the bag ready for another try later, when hopefully weathe will be a bit kinder...

SPAM 2008 - what a difference a year or two makes

(Me above sporting fancy new headgear, a Xmas pressie from Ms Miff, that serves a useful purposed of ensuring I can find my piccies in admist all the others (PS bought the piccies above so will scan in once they arrive))

Well another year has passed. And it ended on a real high when I did the SPAM winter challenge yesterday. This is my bellwether event, despite it being ridden in the UK winter in the wet/cold on a mountain bike, while my preferred choice of ride is on a racing bike in the French summer when it is warm and hot.

The reason for this event's significance lies in history. As mentioned in my previous blog entry I took a new year resolution at the start of 2005 simply to lose weight. I nearly bought a Concept 2 to help with this, realising only just in time that it would be too big to fit into the room intended for it. So I got a Lifecycle instead and never looked back. I lost 2 stone in 2005, getting a whole lot fitter in the process. So as 2005 progressed I started cycling for real, and, as mentioned previously in this blog, came up with the idea of doing the TDF 2006. Come the winter of 2005, I had a goal but that was all.

Starting SPAM - 2006

It was around then I made my first (very naive) visits to Banjo Cycles where a leaflet caught my eye. It was promoting the "SPAM Winter Solstice Challenge" (always just called the SPAM by me). This was to be held in January 2006, with course options of 30 or 50km. As it happened I had been doing some training on (an ancient Decatholon from France) MTB so I thought I would enter as a spur to training and compare myself with other cyclists. I chose the 50km option as it did not seem very far compared to the 150-200km I would have to do in France.

The day of the event came around. I still recall feeling nervous at the start. There were 500 entrants for the 50k and some looked quite fit. However I was quietly confident, after all I had been training all year and was getting quite good on my Lifecycle. I had dreams of coming in ahead of the more experienced riders as I had seen previous year's results with many in the 3-4 hour range. I could do 16kph on a mountain bike easily. So a sub 3 hour time was a possibility. In my more giddy moments I even had visions of coming in first...(well it was just after Xmas when the spirit (well wine and beer at least) had been flowing).

Well they say pride comes before a fall. In my case this was literal. In fact pride came before a number of falls, each leaving me more muddy and dispirited than the last. The weather for the 2006 SPAM was not bad but it was cold with a light drizzle that bound mud to my bike in an icy slushball. I was cold/wet and not going very fast at all. Far from being at the front I was very much near the back, I can recall long periods of riding alone being ever so slightly worried that everyone else may have finished. My old bike did not stand up to the conditions, it became clogged with mud and after a while the shifters stuck so I was effectively in a single gear. Much of the time it took so much effort to pedal it was quicker to get off and walk. I can honestly say it was the hardest event I have ever ridden in.

Still there was a moment of epiphany that I still look back to when I need some cycling strength. At some point in the ride, after what already felt like an age, I reached some marshals who was separating the sheep (following those on the "short" 30km ride) from the 50km mountain biking goats. By this time I was already pretty much at the back of the field. I was asked which route I was following and I said (very wearily I think) 50km. The marshals pointed left, up (another) muddy hill but their faces softened and I was asked very solicitously if I was sure I wanted to go that way. I could instead turn right and downhill to the finish, warmth, hot soup and bananas.

I have to admit I faltered. I thought I was already near the finish. Instead I was only just over half way. I was freezing, my bike was knackered and I was in an even worse state. I could give it all up and head for the finish. No-one would know. I wasnt a member of a club or anything and didn't have anything to prove. That was a crucial test. If I had given up and headed downhill for the finish I dont know if I would ever had started let alone finish my TDF. But I didn't give up, I headed uphill into another 2 1/2 hours of muddy hell.

So I finished SPAM 2006 but only just. I was not in fact last. I finished 466 out of 476 taking 5 1/2 hours. So 10 poor souls were even worse than me! I think they must have finished in the dark. It was all a chastening experience, I realised I had much to do in terms of training. But it also showed me I had the will to persevere if needed and that helped a lot, both in training and events since.

I also had another goal. Finishing the TDF was one thing but the SPAM was unfinished business. It had humilated and almost cracked me. I was not going to let it rest, in Arnie's immortal words "I will be back". (But with a new bike I ditched the Decatholon for a cheap Giant XTC, subsequently upgraded with SRAM gears as the one thing I did not EVER want to happen again was lose the ability to gear change in some muddy field far from home.)

SPAM 2007 - Return and some revenge

So I entered SPAM 2007, which took place almost a year ago. My goals for this event were a bit more modest. To finish better than 2006 (and fall off less). I managed both despite a muddy bath in the first km. I pushed hard all the way round and finished just above halfway down the field in 172nd place out of the 383 who finished. My time of 3:26 was a bit academic as the course was shortened due to bad weather and was more like 40km than 50km. The result left me pretty satisfied and I felt I could hold my head up.

SPAM 2008 - SPAM Surprise

With honour being upheld at the 2007 SPAM I didn't give any thought to the 2008 event. In fact my MTB bike and shoes remained unused and unwashed throughout 2007 as I concentrated on the road, club runs and sportives replacing my MTB rides. I sort of assumed I may do the event but only started to think about it this month, which turned out to be nearly to late as when I checked the SPAM site:

http://www.spambiking.co.uk/index.asp

I found that SPAM 2008 was to be held on 30 December 2007. This was good and bad news. Good news is plenty of time to recover afterwards. Bad is that it meant almost no pretraining and coming right at the end of Xmas week when pud = pounds gained...

I did think if it would be worth entering but then I remembered 2006. If I didn't enter did it mean I was scared? Didn't want to entertain that thought so washed off MTB and shoes and had one run down the canal tow path, pre Xmas. I must say this reminded me of why I liked MTBing so much. Its hard work but fun buzzing around the countryside and maps take on a whole new dimension when you can look for off road shortcuts.

Not being too concerned about doing well I did not let the upcoming SPAM spoil Xmas excess and I ate drank and was merry. Bike and stuff were stuck into the car Saturday night ready for a prompt start and I headed along the now familiar road to Erlestoke. I parked nearby and opened my boot only to find my front tyre was flat and Zen Stone (MP3 player) battery dead. I did an emergency tyre change then headed off to register. I found that the start was not for another 30 mins so whizzed back to the car to charge up my Stone a bit. Made it back to start where I met a couple of guys from Banjo. (One of them was Adam who had taken me out on my first training run back in this mist of time.)

We started off, thankfully not into a muddy field (as happened in January). So no early falls, but there was a steep old hill that I remembered from 2006. Happily I made it up a lot easier and set off. I had no real targets, I had thought about treating the event as an endurance training ride but found my HR following the first climb was much higher so I thought I would just push on. Unbeknown'st to me the course turned out to my liking. After some country sections there was a long road section where I just hunkered down and pedalled. I found that I got overtaken on the country but then overtook back on the road. Anyway I had a great time always just staying on the right side of the red line. I got off and pushed on a couple of hills (simply because it was as fast as riding) but otherwise had a great ride. I didn't fall once, despite some slightly hairy moments. In fact the worse thing that happened was my Stone finally running flat which affected my rhythm a bit. But I made it to the end which came a lot quicker than I expected.

I finished in 2:47, an incredible time and not one I would have thought I was capable of. This left me 102nd out of 336, so now in the top third. Better still its pretty much half the time I did the 2006 event in, put another way I was reaching the real finish of the SPAM 2008 in round about the same time as I met the marshals separating sheep from goats in 2006.

I was pretty elated by this. Especially because though I had pushed quite hard I had never felt on the edge and though a bit tired at the end I felt a lot better (and today feel fine).

PS: My time was good. For me. But the winner did the course in under 2 hours. Respect.

12 months on - 2007 v 2008

It was interesting for me to compare my performances in Jan (SPAM 2007) and Dec (SPAM 2008). Subjectively January was tougher, I trained for the event and gave it my all. However the stats told a different story, as the graphics below show.

In both the yellow section shows HR from 150-170, which is top of my aerobic to sub threshold zone.

2007:

This shows a pretty even split. Overall average is 149bpm, 45% is below 150bpm, 55% above with just a couple of minutes above 170bpm.

2008:

Everything has moved up by 10 bpm. Average is 159 bpm: just 11% is under 150, 79% is in the 150-170 range and 10% (17:15 mins) over 170. The hills at the start kicked my heart into life I kept that going through the road sections. The decline at the end is expected but its only relative to the early portion. Partly its accounted for by me having to slow to fish out food and drink. I also definitely miss my trance music when it stops.

Overall the most surprising thing about the ride, even more than the time, was that with no preparation I set a PB in terms of HR. 163bpm from 1.10 to 157 bpm at 2:56 beat my previous effort on my eyes out Lambourn triangle ride end August. Its some regret that I do not have a Powertap on my mountain bike as I am pretty sure I would have set some power PBs. Maybe next year.....

Weight of my body (and mind)

It being this time of year it seems appropriate to reflect on the progress of my diet. Weight, the mission to shed some, was the route that got me into cycling, kicked off by a New Year 2005 resolution. Back then I was a portly 14 stone plus, I bought myself a top notch exercise bike and some digital scales in Jan 2005 and started pedalling. Progress since then has been pretty good:

(Graph weight in lbs since May 2005 to end Dec 2007, blue line = weight at start of day, red = rolling 3 week average)

Graph above shows how my weight came down steadily through 2005/first half 2006, then stabilising after my TDF.

The graph below shows weight during 2007 remained pretty consistent though with a few ups and downs. The ups came naturally enough around holidays and a business trip to the US. Bizarrely I also came back from my two cycling trips weighing more than when I left. This was not too much of a surprise actually, since the same happened on my TDF, after a hard days riding the temptation to tuck into a good meal is just too much.
My scales also give the option to record a fat%. This can be a bit inconsistent as varies according to the time of day you measure and also if you have just exercise/eaten. I take at the end of each day. Notwithstanding the variances there is quite a clear trend down mirroring my weight loss. The recent trend upwards is puzzling. Not planning to do anything it but will keep an eye on it and see how start of harder training affects it.

Cardiac Drift Test

I decided to try carrying out a cardiac drift test yesterday, to complement the MAPs I have been doing.

Logic is that these should provide an indication of how my aerobic capacity is faring. Given that's the most important for the events I ride makes sense to see if I can check it.

So did a relatively simple test. Set my Lifecycle to Watts, 200W for 40 mins, put on an episode of the Sopranos and pedalled until the credits came up (50mins or so later so got a warm down in as well.). Reason I chose 200W is that it is towards the higher end of my endurance zone of 157W-212W calculated a la Coggan from an FTP of 280W.

Then looked at the HR curve, treating the first 10 mins as a warm up then looking at the next half hour breaking it down into 2 chunks of 15 mins.

Result below (Y axis 110-140bpm):

Shows that in fact took me about 25 mins to get me warmed up then flattened out around 137 bpm (about 75% of my MHR c. 182) So will take out from this:

• My 157W-212W estimate of my endurance zone is in the right area but maybe a little low.
• I should plan to redo the test watching a couple of episodes and see how much my HR changes once I have fully warmed up
• I will try again but in my tempo (213W-254W) zone.

LEL 2009: I am in...

Received an acknowledgement for my LEL 2009 entry. So I'm in, now, as the web site tells me, just another 585 days, 14 hours, 48 minutes and 56 seconds to prepare

HAC4 vs Powertap

Finally sorting out a fixed bike is good news but gives rise to the question of how I log rides in WKO, since natch it has not got any power meter.

However I do have a HAC4 computer, which gives a measure of estimated power based on riders speed, weight and ascent. The manual that comes with the HAC says that this is accurate to +- 20W on climbs and +-40W on the flat.

I thought I would carry out a test to check this out. So yesterday I made two rides along the same 18km course, one with my fixed bike+HAC4 and the other with my Giant winter bike+Powertap.

Both bikes had the same tyres (newly fitted Schwalbe Marathon pluses) and both+me weighed pretty much the same 85kg (which was the weight I entered into the HAC)

The weather was cold but very still, with no wind to speak of.

I chose a course that took me out and back to Kingsclere, the next village. It consists of a short climb just after the start and again just before the finish. (see below). There are no junctions or other reasons to stop on the road so I could make the rides pretty similar. I did the first on the fixed then repeated on the Giant. For the second ride I used a constant gear with the same ration as the 42x18 on my fixed. I used HR to pace, trying to keep second ride same as second, taking both rides easy. The only issue I encountered was that I accidently switched my light on during the first couple of minutes on the fixed, which messed about with the HR until I switched it off.

(Course profile above showing 2 climbs and the rolling middle section.

Once done I downloaded the Powertap file into WKO and exported into a csv file so I could use Excel to compare. The HAC file was loaded into Hactronic, then I used Snagit to save the raw data into a txt file, again to be used in Excel (pain having to do this but don't know of way to save raw data with power).

Results were quite instructive. I managed pretty well in terms of HR as the graph below shows.
(HR comparison, Powertap is red HAC is green) The funny HAC data at the start of the ride can be seen but afterwards the two graphs pretty much track each other, being slightly offset due to differences in ride speeds)

The power readings make interesting viewing:

Here the green HAC line seems to track the red Powertap one quite well through the two climbs but in the middle, rolling, section is much smoother and consistently less than the Powertap. (The smoothing is probably due to the HAC sampling every 20secs rather than 1sec, but this does not account for the difference in outputs.)

In terms of numbers a comparison of the WKO evaluation of the two rides is below:

This confirms I did pretty well in keeping HR constant and also shows how the power measures (Work, TSS, NP and Power) are all 11>25% up when measured by Powertap.

Breaking the ride into sectors explains the difference a bit more:

The climbs show much better correalation between HAC and Powertap in terms of average. (Maxes will always be a problem for the HAC given its sample rate). However the rolling mid section shows the average power is significantly different, in fact pretty much by the 40W HAC say will happen.

I used this to play around with the HAC file. After a bit of trial and error I found that adding an arbitrary 20W on each HAC4 record with a gradient of between 1 and -4% yielded a TSS and average power prettty much the same as the Powertap and the graphs between the two were more alike. Most of my rides will be similar in terms of terrain so will use this as a frig factor for purposes of upload to WKO in future.

Riding Fixed

I finally got around to converting my Langster to a fixed wheel yesterday. This was a bit more complicated than expected, due to me also fitting Schwalbe Marathon Plus 28s so as to do all I could to guarantee that I would not get any punctures. These tyres were just a bit too big for the brakes and so I ditched the latter, since they are (I am told) redundant if you are riding fixed.

I did a cautious first run down the road to Kingsclere and back. After a while I got used to the fixed sensation and found everything bar going down hill good fun. I did a follow up ride on my winter Giant next and noticed I was a lot more aware of the pedalling action. So will continue with a few fixed excursions