Friday, June 29, 2007

FTP Testing and Hammerhead Sharks

Accurate functional threshold power (FTP) testing can be a little tricky. It's rare that you'll get to measure the real number directly -- that can only happen when riding a 1-hour TT effort in competition on a bike with a power meter (my TT bike has none). But you need an accurate number because you use it to set up all of your interval training power ranges. Therefore, you have to use other methods to test for and calculate your FTP.

Analysis paralysis warning: If you're not really, really interested in FTP, save yourself the pain, stop reading here, and just check out my birthday present from Betty Jean instead. I think I'll call him Clayton -- Jeff seems to enjoy hammering as much as anyone I know.


Ok, back to the numbers. In converting other testing numbers into an accurate FTP value, you have to consider the racing vs. training factor and also, if using a trainer for testing, a factor for converting your max effort on a trainer to your potential effort on the road. And finally, it's hard to do 1 hour all-out tests. I do three a year. Between those tests, I keep track of FTP by doing 20-minute efforts and using factors as described below. So you have the 20m to 60m conversion factor too.

I ran a 20-minute test last night on the Computrainer to try and establish the wattage relationship between a 20-min computrainer (CT) test and a 20-min test on the road. I started out way, way, too hard, but leveled out eventually and ended up with average 20-min wattage of 268, which is exactly what my last hour-long road FTP test calculated as my FTP. It’s also exactly 95% of my peak 20-min wattage in the Edgar Soto TT a few weeks ago. Also, it’s interesting to note that the CT gave me the exact same average wattage as did my Ergomo, so they matched perfectly.

So there are a couple of things going on here. First, I’ve become very confident that the relationship between 20-minute average wattage and 60-min (FTP) wattage is 0.95. I have multiple tests showing that my maximum 20-minute power output in races is 95% of my calculated FTP. So I’m holding fast to that relationship. I’m also pretty confident in the training-to-racing 103% relationship (adrenaline/motivation in races allows you to generate about 3% higher wattage over 1hr than in training) is accurate. What I have now is a new relationship between CT testing and road testing in training.

So here are some conversions. First, my designations are:
road = training on the road
CT = training on the Computrainer
race = data from a race

FTP has always been defined as 1 hour race average power:
FTP = 1.00 x (60m – race)

In a 1hr training road test, we increase measured power by 3% to account for adrenaline, motivation, et cetera:
FTP = 1.03 x (60m – road)

A 20-minute race TT gives you 5% higher average power than your 60-min race power, so:
FTP = 0.95 x (20m – race)

For a 20-minute non-race test on the road, we have to throw in both the 95% conversion from 60m to 20m and the training/racing adrenaline factor:
FTP = 0.95 x 1.03 x (20m – road) = 0.98 (20m – road)

Ok, here is the new stuff that I've just figured out:
For whatever reason, I’ve found that power output on the Computrainer is about 2% less than non-racing testing on the road for an extended effort (probably due to heat, lack of breeze, inability to move around, mental factors). So we need to account for that extra 2% with a third factor of 1.02, so:
FTP = 0.95 x 1.03 x 1.02 (20m – CT) = 1.00 (20m CT)

So when all is said and done and you get rid of all the numbers, you end up with a very simple relationship for testing FTP:
FTP is your average 20m power on a CT. That's without a doubt the easiest, most consistent way to test.

Wednesday, June 27, 2007

Cycling Peaks graphs

After seeing the power graphs I posted the other day, someone asked how much and what type of data the Ergomo collected on each ride and how it can be viewed. The answers are: more data than you would ever want to view for each ride, and I store/view it in CyclingPeaks software. Once in a while the more detailed graphs are useful. Here are some examples of ways you can view the data. All of these charts reflect Tuesday 6-26-07. As usual, click to enlarge:

Friday, June 22, 2007

Raw power charts

A few folks have inquired about seeing some raw power data, so I've thrown in some charts from the past week.

This first one is from the Savannah Georgia Cup crit last Saturday. It's obvious that it's a crit because of the consistent power spikes required to accelerate out of each corner (there were only two corners on the half-moon shaped course). To prepare for a race like this, doing about forty 10-second intervals at 600-700 watts with 200-watt, 30-second recovery would be about right. I rode at the back a lot and the yo-yo effect makes the cornering 'intervals' even more distinct than they would have been up front.

These two power charts are from yesterday's Macon ride. Keith rolled off the front (he might have just planned a short jaunt) and I went up to join him and turn it into a 35-minute suicide mission. It was a futile effort, but great training. The first chart is with no data smoothing and the second is with smoothing (30-sec running average, I think). The horizontal line is my functional threshold power (FTP) of 268 watts. My normalized power for the effort was 289 watts, so I think it's time for me to test FTP again.

Wednesday, June 20, 2007

How to win the flats - Savannah

The Savannah Georgia Cup courses last weekend were flat - that was no surprise. The TTT course had a few rollers and some breeze, but the crit and the circuit were open, flat, and the wind effects were present but minimal. I assumed going in that I had virtually no chance to win or place high in races on flat stages where a sprint finish was very likely. I've been thinking about why I made that assumption beforehand and about why it was an accurate assumption.

Trey and I formed a 2-man team for the TTT. On a flat course with a couple of short, small grades (2-4%) and a light breeze, we averaged 24.3 mph over about 14 miles. That corresponds to something between 280 and 300 watts average power output over half and hour. That seems reasonable, because my FTP is about 270 and Trey's is probably somewhere in that range also. That means each of us was essentially doing 1-minute intervals at 280-300 watts with a one minute 'rest' at about 240 watts or so. Our TTT experience was virtually identical to what one would expect to face in a two-man break off the front of a circuit or crit (except for the less aero road bikes vs. TT bikes).

The average speeds for the competitive division (4/5) crit and circuit were just under 26 mph, and both races had fairly consistent speeds. That means that the riders at the front of the peloton at any given time were riding at about 325 watts on the flats with no wind. That number seems reasonable. In order for any rider or pair of riders to get off the front and sustain a gap, they would need maybe 30 seconds of 400 or 450 watts to get away, then a sustained 325-350 watts just to maintain the small gap. Unless I'm mistaken, there aren't many category 4 or 5 riders who can generate that kind of sustained power. I can sustain 385 watts for a couple of minutes or so, but would probably not be able to ride at a sustained 300 watts for any length of time afterward. That's why my assumption about not being competitive in Savannah held true. As a matter of fact, both the crit and the circuit ended in a bunch sprint. Evidently there were no riders in our races that had the kind of power I described above.

And it gets even tougher in the elite and pro, 1, 2 races, where I think the average speeds were at least 27 mph and 28 mph, respectively.

Thankfully for me, all that I have said above goes out the window on courses like Dahlonega, where pure wattage takes a back seat to watts/kg and top speed pretty much disappears from the equation. It doesn't mean I'll podium in Dahlonega, it just means I'm not almost mathematically eliminated before I start.

Monday, June 18, 2007

Savannah Georgia Cup

The GA Cup races this weekend in Savannah were very flat and very fast. Racing from Macon were Trey Gavin, Jeff Clayton, Chad Madan, myself, and Richard Cook.

The Saturday morning Team Time Trial was the toughest of the three stages for me. Trey and I formed a two-man team (the minimum for Competitive division). It was a flat 14-mi course with a few small inclines and a light breeze on half of the route. We started out too fast with too much adrenaline, I think, and had to struggle to keep up the pace at the finish. But all in all we had a good TTT, passing the groups that started 1 minute and 2 minutes ahead of us, both of which were 3-man teams. Our average speed was 24.3 mph. It would have been very beneficial to have had one or two additional teammates. The draft effect would have been larger and it would have provided a critical extra few seconds for catching our breath between pulls. But it was a fun ride. We finished 11th of 20 teams and beat all the 2-man, 3-man, and 4-man teams. A GA Cup screw-up on the web site caused Jeff to miss his TTT start. Richard was paired with another single and had a good ride. I think Chad's team took 4th.

The Saturday afternoon 'crit' was hot. They called it a crit, but really it was a short, half-moon shaped circuit race with two open, wide turns. Trey and I both stayed with the front group in a race that was very fast by cat 4/5 standards (25.8 mph). I moved up to the front a couple of times, but didn't have enough juice to try anything. Trey raced aggressively and stayed up front a lot. He took 2nd in a time bonus prime and finished top 20 in the sprint. I was probably at about 30th. I didn't realize until after the race that they didn't give the same time to everyone finishing together in the final group, so I lost a few seconds there. Jeff raced well but finished mid-pack in his race, and I think Chad finished mid-pack after doing quite a bit of up-front work for Pacesetter earlier in the race.

The Sunday circuit race was on a wide, fast mini-Indy car track with about 7 turns. It was another very fast race (25.7 mph) with wide open turns and some breeze. It finished similarly to the crit for Trey and I, but included much more carnage. At least four crashes occurred during the race, with one guy breaking his collar bone, I think. Lots of scraping aluminum and cracking carbon (road rash makes no sound). Jeff covered all the breaks in his race, but none of them stuck. He finished mid-pack in the sprint.

I guess you can see that the theme down there was fast, open, sprinter's races. The TTT pretty much set the finishing order in the GC, and we don't have many sprinters from Macon, so we didn't bring home any hardware, but it was a fun weekend. Dahlonega in two weeks will see an entirely different list of names on the leaderboard.

Monday, June 11, 2007

BBQ Bass

Lunch stop at the BBQ Bass ride. Click to enlarge.

Wednesday, June 06, 2007

Rock 'n Rollman

I had a good ride at the Rock 'n Rollman 1/2 IM on Sunday -- I bettered last year's time by about 21 minutes and finished in 2:33:45. I'm glad I rode well, and I want to identify what I did right so it won't be a one time show. I have several theories, and it's probably some combination of all of them:

  1. More mileage - My mileage/training time since April hasn't been drastically different than what I've done in past years, but it's a little higher (150-200 miles/wk this year compared with 100-200 miles/wk last year). The real difference was during the winter months. I averaged about 150 miles per week instead of 75. And a big chunk of that riding was in the Peach Peloton in 60-135 mile rides. Those long winter rides probably helped me build a bigger aerobic base, which allowed me to keep my heart rate steady at 155 bpm (7 bpm below FT) throughout the ride instead of having it decay steadily from 155 to 130 like it did last year.
  2. Weights - I hit the weights over the winter -- mostly squats and leg extensions. I'm not sure the lifting really helped me, but it is a difference from last year.
  3. Psychology - I think this was the big one. I've never argued that the mental approach to sports performance is important, but I think this ride was the first time I took full advantage of it. There was a steady brisk breeze in our face from the start to the half way point in Roberta. Instead of bitching and moaning about the headwind (like I heard lots of my competitors doing), I was begging for it not to stop because I had convinced myself (accurately, I think), that I was more aerodynamic than most riders (small body size, TT helmet, skinsuit, tri-bike w/aero wheels, shoe covers, etc.) and that the harder the wind blew the more time I was gaining on them. Also, I didn't have to run after the bike because I was on a relay team. That allowed me to leave it all on the road, mentally and physically.
  4. No swim - Because of the relay team I didn't swim before the ride. This obviously gave me some advantage, but I don't know how much.
  5. Tandem riding - This one was unexpected. I've done some tandem riding with Betty Jean this spring. It's made me much more aware of the effect of momentum on riding rolling hills. On a tandem, momentum is a much, much bigger factor than it is on a single. I've learned that increasing the effort in the last 1/4 of a short climb can make a big difference on your speed down the back of the hill. So I jumped out of the saddle toward the end of most small climbs to maintain momentum for the decent. I'm convinced it made a difference in my downhill speed and had the added benefit of improving the blood flow to my leg muscles, which is an issue that I almost never hear mentioned but I think is important. "Attacking" the hills also was good for the mental game.
  6. Aero equipment - I picked up a LG aero helmet on eBay for $60 and a Colnago skinsuit for $40. I know they made some real difference (as much as a few minutes), but they definitely make me feel faster, and that's probably more important than their actual effect (see number 3).

Cycling improvement is a combination of lots of small things. One at a time they may not make a noticeable difference, but together they do.