PezCranking: Two Months Down Under
Tuesday, April 19, 2005  5:09:10 AM PT

by Dr. Stephen Cheung, Ph.D.

Our Toolbox Editor has spent the past two months putting his PowerCranks (and sunscreen) to serious use during his stint in the flats and hills of New Zealand’s South Island. Here’s the latest batch of lab and field test results from Down Under and upon his return to Halifax…

I have just returned to Halifax from two months spent in the cycling nirvana of Dunedin, down low on the South Island of New Zealand. I received the PowerCranks a week before my departure, giving me just enough time to get an initial set of baseline testing done and a few short rides on the trainer. I debated tossing in my normal cranks into the bike box, but decided that the only way to give them a true test was to go cold turkey. So PowerCranks or bust!

Just the Facts…
So what did I get up to bike-wise while I was in NZ? First, check out my first Baseline article on the PCs to see my baseline fitness and a report on initial adaptations after 3 weeks:

• 2063 km, 75 h of cycling. This may not appear to be much for two months, but keep in mind that I spent the first few weeks with pretty low mileage to adapt to the cranks. This amount of riding is also typical of my mid-season. My longest rides were about 3 h and 90 km, which I completed fairly strong throughout at a steady group (not race) pace.

• 21,000 m of climbing total. I didn’t even seek out climbs – it’s just steep all over, although there were lots of flat routes too.

• Most of my riding consisted of unstructured training of base miles at a fairly steady pace. This was to adapt to the PCs, and also because I was not aiming for highly specific training in Feb/March anyway. I did do a few random hard efforts or rides, along with a few fast group rides and a race while visiting Christchurch.

• How did my race in Christchurch go? It was a mass start all categories race of 125 km and frankly, I sucked. The Kiwis were in mid-season flying form and I found it extremely tough with the PCs to have the high cadences necessary for fast pack riding. It was the same story with other hammer rides. Part of it was certainly the fact that I hadn’t done much interval work, but my hip flexors and tibialis anteriors (shins) completely cramped up from the high power surges and high cadences.

So overall, I was a recreational tourist while I was there. Not really noodling around, but not altogether structured and hard-core interval training either. The real question that we will address at the end is just how much of the changes I’m about to detail below stem from the PCs, and how much simply from riding consistently and more than typical for the time of year?

By the Numbers
It has been really interesting returning to Halifax after an extended time away, as it has allowed me to come back to riding the same familiar local routes with “fresh” eyes. In turn, this gives me a clear separation so that the changes are quantum rather than caught up in day-to-day changes. As Frank Overton wrote concerning field tests, riding the same courses has revealed the following changes:

• It was getting to be early fall in New Zealand and getting cooler. But the weather back here in Halifax was still far colder, requiring me to dig out all my winter gear again for the first two weeks back. Therefore, if anything, my performance should have been negatively affected by the colder temperatures.

• My cadence when first using the PCs was about 70-75 rpm. It is now about 88-92 rpm when cruising on the flats, although I can do speed intervals in the 115-120 rpm range for 1-2 min efforts. I can climb at cadences from 40 rpm grinding up the steep Dunedin hills to relatively spinning at 85 rpm for prolonged periods. However, the hardest part I have found is rapidly increasing cadence after cresting a hill.

• My usual commute to the lab is 14 km of rolling roads, usually taking me 30 min. With my PCs, I’m consistently chopping 2 min off my commute time each way without trying to hammer.

• My PowerIndex on my Polar power monitor has gone from ~17% on flat roads to consistently 24-26% now after two months, indicating a far smoother pedaling stroke throughout the entire 360 degrees.

• My right leg was originally less smooth than my left, and it certainly felt like it initially with the PCs. It has almost reversed itself now, with my right leg very comfortable with the PCs and my left one more “jagged” and prone to cramping in my tibialis anterior unless I ease into the effort during the first 15 min of riding.

• My heart rates during endurance rides were initially much higher when first using the PCs, but have now dropped back to “typical” levels of 130-140 bpm but at power outputs of 10-15 W higher.

Turbo-Rocket
The other big question is what would riding on “normal” cranks be like after an extended time on the PCs? I’ve spent a few rides over the past couple of weeks tandeming, commuting, hauling groceries and two growing boys, along with a ride on my winter road bike. The best way to describe the sensation is like you’ve just installed turbo boosters in your shorts. Simply put, pedaling becomes ridiculously easy, and you finally realize how little you normally pull up on the upstroke phase.

It has been no problems sustaining higher cadences and power outputs back on normal cranks, especially as the cranks almost seem to fly through the upstroke phase without any conscious effort. Better yet, when I hit a hill or need a little boost in power output, rather than shifting gears, I simply remind myself to “pull up” even more and there is a noticeable elevation in cadence and power. I haven’t done any biomechanical analysis on my pedaling yet, but I also seem to have changed my pedaling action. I’m still fairly neutral (in terms of toes-down or heels-down) at the bottom of the pedal stroke, but I appear now to be much more of an “ankler,” with a more toes-down action on the upstroke. I believe both of these observations are testament to the strength gains in the hip flexors driving the pedals around through the upstroke.

Hillclimbing Field Test
My parents always go on about how much my two boys change each time they come to visit. After two months away, I now know exactly what they mean. One ride that I always dread each year is the first time out with them in the trailer behind me. That’s because they’ve spent all winter growing, while I have generally dropped in fitness.

The first ride back here in Halifax with the boys, however, was an amazing revelation. After taking them around town for a day, I faced the usual climb up Cowie Hill, 70 m elevation in about 1.2 km. Keeping in mind that the boys grew a collective 4-5 kg over the winter, and that this was my first ride of the year with them, I still climbed comfortably up Cowie in 2 (!) gears higher than I ever have, even at the end of last summer after training for France and riding the climbs there!

Summary to Date
So with my experiences to date, I feel that I have definitely changed as a cyclist after using the PowerCranks exclusively over February and March. There is a higher output at the same heart rates, bigger sustained gears, and a dramatically improved ease of pedaling upon return to normal cranks. Except for training races, I wouldn’t use the PCs for racing until I put in more interval work and build up my capacity for sustaining high cadences.

Are the improvements due to the PCs or the bike-time I put in? While some of it is certainly due simply to putting time on the saddle, I’m convinced that my pedaling action has changed in ways that simply riding more could not change. Also, the field tests and the objective numbers since my return demonstrated clear improvements in gearing, ride times, etc. that exceeded my typical mid-summer form, even with no specific training. Therefore, I feel that the majority of the benefits has been due to using the PCs.

I’m off to spend May and June in Slovenia and to chase the Giro in late May, and will be focusing on MAP intervals and building up higher cadences with the PCs over the coming months. Look for another progress report post-Giro!

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