Post 13 - Bike science

And so another week passes on the physical, mental and emotional rollercoaster that is Ironman training. Towards the end of last week I could barely walk, never mind put on a pair of running shoes, as my back had seized up so badly for no obvious reason. At the end of this week, my back has improved, there have been two consecutive days with temperatures pushing 20 degrees Celsius, and I have had another solid, if somewhat tentative week of training. It takes a long time to build confidence again after an injury, and that confidence can be shattered in a matter of moments. I’m hoping that my back problems are now over, but I know that I’ll need to be very careful.

Training this week was as follows:

Monday 10^th March 2014: Rest
Tuesday 11^th March 2014: 1:10 turbo (1 hour hard)
Wed 12^th March 2014: 30 minute fartlek run
Thursday 13^th March 2014: 2 hour turbo (pyramid session), 20 minute run
Friday 14^th March 2014: 2.5km swim (10 x 200m in 1:30, 10 second recovery), 1 hour turbo (single leg drills)
Saturday 15^th March 2014: 3 hour turbo (harder every 15 minutes), 30 minute run
Sunday 16^th March 2014: 4.25km swim (sets of 250m, normal/with paddles), 75 minute run

 

Totals: Swim 6.75km, Cycle 140 miles, Run 24 miles


I am very tired after this week. My cycling mileage continues to increase, my swim sessions are getting tougher, and my long run distance is increasing. I need to get back to doing my weights and squats as I have been holding off doing them, because of my lack of confidence in my back. All things considered however, this has not been a bad week.

I currently own four bikes, or rather I own three and am still paying one off. One is in Northern Ireland, and was my first Ironman bike. I still ride it when I go home. One is a cheap hybrid run-around, one is my triathlon/time-trial bike, and one is a nice road bike I bought off a colleague for a good price. When I did my first Ironman, it was on a fairly cheap, entry-level road bike, that wasn’t properly fitted. This meant my riding position was very inefficient, and not only does this have an impact on overall bike performance, it is also detrimental to running performance. A triathlon bike can, and indeed should, be optimally set up to make the transition from biking to running as easy as possible. This transition is a bit of a shock the first few times it is practiced, because after hours spent on a bike, legs do not work properly when subsequently trying to run. Many a first-time triathlete has jumped off their bike to try to start running, and fallen flat on their face.

 

The images below show my attempts to properly set up my first Ironman bike:

Furthermore, this entry-level bike was about as aerodynamic as a barn door, and I was subsequently told by a bike shop that its wheels were “junk”. Its set-up was a baseless, botched job, and I now look at pictures of myself on it, and I wince and cringe. Up until a couple of weeks before Ironman UK 2011, I was still messing around with seat position and handlebar height. Nonetheless, I made the most of the resources I had available, as I couldn’t afford a “good” bike, and I still rode this bike to a top 12% time at Ironman UK in 2011. I then followed this with a 2000 mile cycle from Land’s End to John O’Groats and on to Orkney and Shetland. So it’s not that the bike was “bad”, it was just inadequate for competing at a fairly high level in an Ironman.

It was versatile if nothing else, it made it to John O'Groats,
and Orkney and Shetland, carrying luggage too

When I decided to do another Ironman, I knew that I’d have to get a better bike and have it professionally fitted, to optimise both my cycling performance and my running performance. This involved accepting that significant sums of money would have to be spent. So, I bought a nice triathlon bike, with nice wheels, and nice bits and pieces, and paid a significant sum of money to have it insured. Being able to ride this bike meant that a basic, entry level bike with junk wheels would no longer be an excuse.

 

I’m uncomfortable with the idea of “buying speed”, and that the playing field in triathlon is not “level”, in the same way it is for a sport like running. After all, anyone who wants to spend £50 on a pair of running shoes can do so, after that, success comes with hard work. In triathlon, hard work is of course essential, but there’s no denying that it’s not a cheap sport, especially at high level. Without the equipment, it's difficult to fathom competing at high level in an Ironman.

 

I had my triathlon bike Retul-fitted at FreeSpeed in Chiswick in London, by a former Ironman World Championship qualifier. It was excellent. A “Retul” bike fit is a 3-hour marathon session, where I paid a significant sum of money to first of all have my feet and shoes analysed, cleats optimally placed, insoles customised, and then have electronic sensors placed all over me. With wires hanging off me like I had just been created in a lab as a scientific experiment, I jumped on my bike, got wired into a computer, and got told to pedal.

 

While I was pedalling, these sensors were feeding data into a computer, which was automatically working out all sorts of parameters, distances and angles, including knee ankle flexion, knee angle extension, knee forward of foot, knee lateral travel, hip angle closed, hip angle open, hip to wrist vertical, hip to wrist horizontal, hip foot lateral offset, elbow angle, thigh length, shin length, maximum ankle angle, minimum ankle angle, ankle range, knee travel tilt, hip vertical travel, back angle, hip to elbow vertical, hip to elbow horizontal, shoulder angle to elbow, shoulder angle to wrist, forearm angle, knee tracing and cadence.

 

 

This exercise was repeated on the left side and the right side, and then my fitter made some adjustments and tweaks to try to get all of these angles and dimensions within a pre-defined set of ideals. He did observe that I was quite an efficient pedaller, which I was happy about. The whole process was repeated three times, with significant input from myself about how I felt. Setting up an Ironman bike is very different from setting up an out-and-out time trial bike, because after the 112 miles on the bike in an Ironman, there is the small matter of the marathon to come. I showed my fitter a photo of me on my first Ironman bike and he laughed and asked, “How was your marathon?” “Disappointing” was my response, and he wasn’t surprised, because to him, my position was poor. In particular, my hip flexor angles were not open enough, meaning a very uncomfortable marathon to follow.

 

The images below show my Retul fit, and also out on the road. Contrast these photos with the previous photos of my first Ironman bike. There is a big difference in terms of positioning, and also in terms of the bike itself, and the wheels.

 

 

Anyway, when I was optimally fitted, I observed that I was a bit more “upright” than I expected to be. This was in an effort to keep the hip flexor angles open, prevent them from fatiguing, and allow me to run better off the bike. Setting up an Ironman bike, he assured me, is an exercise in compromise, and he was confident that the bike was as well set up as possible. He then used a sensor to measure out every single bike parameter, dimension and distance.

I was presented with a report containing all of my angles and measurements, and which also contained all my bike parameters including saddle height, saddle setback, arm pad stack height, saddle angle, seat tube angle, grip angle, grip width, frame stack, frame reach, handlebar reach, handlebar drop, arm pad reach, arm pad drop, grip reach, grip drop, arm pad to grip reach, bottom bracket to grip reach, arm pad width, handlebar stack and handlebar reach. Theoretically, this data can be applied to any bike, so if I ever buy a new bike or borrow a bike, the data in this report can be used to set the bike up for me.

 

The position feels really good to ride, but the most noticeable difference is how easy it is to run off the bike. After hours on the bike, it almost feels like I haven’t been cycling at all when I start to run. This is a big contrast to how I felt trying to run off my first Ironman bike, when my legs just felt plain awful, my stride felt stunted and curtailed, and the legs wouldn’t do what they were supposed to and what the mind wanted them to do. It’s good to have full confidence that the bike position is as good as it can be and it’s good to run comfortably off the bike.

 

The ultimate question: How much time is a good bike and a good bike fit worth? Well, at Ironman UK in 2011 I rode 5 hours and 55 minutes for the hilly 112 mile course. At Ironman UK in 2013, in similar conditions, on the same course, I rode 5 hours and 30 minutes. Was I fitter in 2013 than 2011? Possibly, but not a great deal. I had done more training in 2011, but I had done smarter training in 2013.

 

The parameters, angles, and riding positions are different depending on the type of bike. So, there are four types of Retul fit: one is a mountain bike fit, one is a road bike fit, one is a time-trial bike fit, and one is a triathlon bike fit. So, when I bought my road bike off my colleague, I had another Retul fit done on it. This was done a month or so ago.

 

Before this fit was done, I went to the Giant bike shop in London to buy a couple of saddles, which I intended to try out at the road bike fit.

 

 Decisions, decisions...

 
There was a WattBike in the bike shop and I asked if I could have a go. A WattBike is basically a souped-up exercise bike. It can be totally customised according to data taken from a Retul fit. It has a screen which provides real-time info on cadence, heart rate, power balance and power output at every section of the pedal circuit.

A WattBike, with handlebar-mounted data screen

 

 

A WattBike screen display

 

I was only wearing my work clothes and a pair of trainers, but was interested to try it out. It turned out that despite having been told that I am quite an efficient pedaller, and despite probably being quite an efficient pedaller relative to many cyclists, in fact my pedal stroke still has a lot of room for improvement. The real-time graph of my pedal stroke fell somewhere between the "beginner" and "intermediate" graphs below, and ideally it should have been approaching a circle shape.
 

 

The ideal graph has an evenly distributed power output through every phase of the pedal stroke. Broadly, the pedal circuit can be divided into four. Each foot will push down, “scrape” back, pull up, and “kick” forward, with smooth transitions between each phase. Throughout the pedal revolution, the power output should ideally be even, indicated by a circular graph. In practice, as illustrated by the "elite" graph above, it's very difficult to have a perfect circle, because it's obvious that a cyclist can push down on the pedal with more force than he/she can scrape back or kick forwards with.

 

My “figure-of-8” graph indicated “dead-spots” in the pedal revolution, with a power distribution heavily biased towards the downstroke. Admittedly, I was only wearing trainers and not cycling shoes, and I feel the graph would have been tending a bit more towards the ideal if I had been wearing my cycling shoes and had been clamped into the pedals, and thus better able to scrape, kick and pull, rather than only pushing down.

 

The guy in the shop told me to only think about “scraping back and kicking forwards”, not about pushing down. This was somewhat counterintuitive, to "ignore" the act of pushing down on the pedals. I tried it, and I was surprised to see immediately how much more like a circle the graph became. So this was an important lesson for me, which showed me that I need to work on pedalling efficiency. So I have built single-leg drills into my training week, where I pedal for set intervals with only one leg to develop all four phases of the pedal stroke. Hopefully this will help to make a difference. I'd be interested, after a few months of training, to have another go on a WattBike, with my own cycling shoes on, to see what my graph looks like. 

The shop guy then suggested that I try the maximal power output test. If I remember right, I was fairly comfortable spinning at 250-300 watts. The maximal power output test requires an optimal resistance to be found, and then riding absolutely flat out at this resistance for 10 seconds. To get a truly accurate reading, the test should be done on a properly fitted WattBike, with cycling shoes, at an optimal resistance, and repeated several times with significant recovery. I had none of this, I just blasted as hard as I could in my trainers and work trousers. I got 850 watts, and I suspect I would have been over 1000 watts if the test had been ideal. By comparison, a top pro or track cyclist would probably output something like 1600 watts. Saying that, some of these guys can leg press over half a ton (Chris Hoy, below) and have quad muscles that look like this:

 

Most of the pros and top amateur cyclists/triathletes will have access to a WattBike. They are handy tools. How much? About £3000… Most/all of the very good cyclists will have power meters and heart rate monitors on their racing bikes, so they can see their power output. They will have trained with their power meters and will know what power they can sustain, and for how long. It must be a good feeling to have these numbers, and to have confidence that you can maintain a given power output for a given time at a given heart rate.

 

It must be a good feeling and a good confidence boost to be 3 hours into an Ironman cycle, knowing that all you have to do is maintain your number, and knowing that you have done it many times in training. It must be a good feeling to be under a threshold heart rate, and to know that as long as you stay under the threshold, you can maintain your power output for 5 hours, and to know that you have done this many times in training. It must be a good feeling start the marathon and know that you can't exceed a given heart rate, and to have run 15 miles of the marathon and to know your heart rate is still under the threshold. Pacing would be so much easier, and you would have a lot more confidence that you wouldn't "overcook" it, and hit the wall, or "blow up", or "bonk", or totally run out of energy.

 

Chris Froome, Tour de France winner in 2013, spent a lot of time during the mountain stages looking at his handlebar-mounted computer, no doubt looking at his power output. He no doubt knew what he could sustain, and kept his power output right on the number he knew he could sustain, that he had trained for months to improve.

Power meters and heart rate monitors would be really useful tools for me, for both training and racing. How much? Thousands of pounds… I have to draw the line somewhere: I couldn’t bring myself to buy a disc wheel earlier in the year and I can’t bring myself to buy a power meter and heart rate monitor either. This really is an “arms race”, as someone put it to me.
 

Anyway, I believe I have the tools I need to achieve my goal. A disc wheel, a power meter, and a heart rate monitor would help, but I don’t believe they are essential. Give me a winning lottery ticket and I’ll buy them. Failing that, I’ll make do with training hard…

 

I’ll also make a few subtle changes to my bike and clothing this year. I will remove both of the frame-mounted bottle cages, and rely on the two mounted behind my saddle (behind my backside and out of the airflow), and also the front-mounted aero bottle between the tri-bars. I’ll have to rely on picking up drinks twice in the race because of this, but I think the aerodynamic benefits of removing the bottle cages will be worth it. I don’t think there’s a lot of point in having such an aerodynamic bike if I am going to completely spoil the airflow with two frame-mounted bottle cages. I will also look at removing the speedometer sensor and magnet from the front fork and wheel respectively, again for aerodynamic reasons. This will mean buying or borrowing a sensorless Garmin GPS device. Finally, I will buy a proper aerodynamic skin-tight racing jersey, and hopefully all of these changes will be worth a good few minutes over 112 miles. This is the philosophy of incremental gains employed so successfully by Team Sky over the past few years.

Bike science is interesting, but there’s a lot to think about! With so much thought, money, technology and effort going into it, I just cross my fingers that something as stupid, as crude, as basic as a flat tyre will not ruin my race. I don’t think I can afford to give away the 5-10 minutes it will take to fix it. Genuinely puncture-proof tyres that are still fast to race on, now there's a niche...