Force Reps

Force Reps

I was just looking at data from a force reps session (each interval is 18-20 pedal strokes at max pedal force in the 53-12). My wattage is typically a consistent 600 watts for the efforts. But the thing that caught my attention was the torque.

WKO+ tells me that my peak crank torque (actually it's virtual crank torque, which is calculated from PT rear hub wattage and cadence) at the max efforts is about 1160 lb-inches. If you divide that by the length of my cranks, 172.5 mm (6.89 inches), you get 168 pounds (1160 lb-in divided by 6.89 inches).

My max squat is just a little more than that. I don't really know my max squat weight, because I never do (and don't plan to ever do) 1-rep max squats. But based on the rep chart in "The Cyclist's Training Bible" I think it's about 190 lbs, which would be about 1.3 time my body weight, which is fairly typical.

The thing that has me a bit confused is that I'd assume most of the pedal force is coming from the down-stroke. If that's the case, I'd only be able to put out a little more than half of my max squat force when pedaling (if you assume the upstroke has maybe 20% of the max downstroke force, it'd be 70% max squat force, or 0.7 x 190 = 133 lbs right?).

I need to think on this one for a while. Feel free to enlighten me in the comments section if I've missed something or messed up the calculations. Am I putting out more force than I think with my upstroke? Am I putting out more than I think with my downstroke due to momentum and body weight factors?

Quadrant Analysis

Here's a quadrant analysis chart of two very different efforts. The one in green is a force rep workout (20-sec of hard low-cadence interval with spinning in between). The one in purple is the 2008 Elberton Crit. All the points above the red line represent segments of effort above my threshold power.

I'm not sure what to do with the information yet, but it's interesting to look at. The most obvious use would be to compare race efforts to training efforts to see if my training is properly race-specific.

Trainer vs. Road

Ok - this is a work in progress. I don't have as much data as I'd like to have, but the general trend is clear. The problem with collecting additional data is that my aerobic system is improving, which makes establishing a true best-fit line a little like trying to hit a moving target. But you'll get the gist of it. The magenta line is a best fit for trainer data. The red line is a best fit for road data.


The not-so-surprising result: it's harder to ride the trainer than to ride on the road at the same power (all the power data was collected using my Power Tap). For now I'll target my training zones on the trainer using a target heartrate along with the trainer curve to get a target power range. Later I'll do a CP30 test on the trainer, set up power zones from that and see how they compare to the first method. I find it interesting that the difference in NP vs AHR is lower close to threshold than at lower efforts. I would have expected the opposite effect.


Gotta do something to keep the trainer workouts interesting, right? But I have discovered a new indoor toy for indoor rides: I downloaded the new Computrainer scenery pack. Now I can ride cyclocross trails through downtown Atlanta scenery. That's different.

CTL and FTP History

One of the useful things about power data is that a watt in 2006 is the same as a watt in 2009. So chronic training load (CTL) and functional threshold power (FTP) are reliable in comparing training and fitness across multiple years. If your power meter is giving you good numbers (close your eyes and accept it, Hoppa, it won't hurt), then CTL and FTP are 100% valid indicators of how hard you've worked in any year and what FTP benefit you developed from the work. The comparison works best in the winter FTP-build phase.

The comparison is a good test of your training program's effectiveness. There are important contributors to, and indicators of, fitness and succes other than CTL and FTP (genetics, luck, nutrition, weight, confidence, stress level, sleep quality, team strenth, equipment weight and quality, spousal support, tactics, strategy, motivation, sprint power, crank torque, 5-min power, cadence, CdA), but for me they are the ones that matter the most.

2008 Racing MMP

Jtheskier from New England suggested I compare mean maximal power from race to race. I thought it was a good idea, so here are MMP charts for some crits and road races. These are cat 4 races, mostly in the Georgia Cup series - all in 2008.

I found it interesting that in crits and road races, I come nearest my season-best power in the 2-4 minute range. For those wanting to convert to w/kg, I weigh 66.8 kg (147 lbs).

Come-Back Shot

Those of you who weren't asleep in math class might remember what an asymptotic curve looks like. Like it or not, my cycling ability is beginning to asymptotically approach the level that I can reach while keeping a job and a wife. It's getting harder to see improvement. That just makes it sweeter when I do set a new power record or accomplish a goal. In the KOM on Sunday, I decapitated my previous 1-minute power record, as shown below. When I was addicted to golf, I'd call that a come-back shot - the one shot of 80 or howevermany that makes you want to come back and tee it up again next weekend.

More Pipp TdG Power Data

I downloaded the WKO+ file for Frank Pipp's TdG ride on 4-22-08. There are several interesting things about the data. The first is that his race was divided into five distinct segments that are all very different. Frank Pipp is 5'9" 155, the same as me. If you're heavier, you'll need to consider that when looking at the power data. Frank has a FTP of 364 watts (5.2 watts/kg).

First, he spent the first 11 minutes just tooling around at 163 watts NP. They were probably doing the parade through town on the way out. 163 watts NP is a recovery day strolll wattage.

For the next 1 hour, 22 minutes, Frank was on "Break Duty" for Health Net. I guess he sat at the front and either tried to go with all breaks or chase down the ones he missed. His normalized power for this segment was 309 watts. For comparison, I'm a typical cat 4 and can hold 309 watts NP for about 40 minutes max. So this is more than I can do, but I ride with several cat 1s, 2s, and 3s who could do it as long as the peak power output was not a limiter - I don't think it would be.



Then Frank gets the long-awaited (I'm guessing here) message in his earpiece that he's off break duty and can chill for a while. And he really does chill. For the next 1 hour and 39 minutes, his normalized power is only 189 watts. Now, I'm fully aware of the power savings benefit of sitting in the pack, but this is really quite easy. I think my wife, Betty Jean, could do it. His wattage doesn't get over 300 watts very many times, even on a rolling course. They averaged 23 mph during that stretch, which seems high considering the wattage. Maybe he's just super efficient?



Then for the next hour the race begins to approach the finish, and Frank's NP is 248 and average speed is 25.2 mph (40 kph for y'all across the pond); that's a decent effort, but easier than solid tempo for a pro.



Then Mr. Pipp earns his money. For the final 24 minutes, his NP is 378 watts and his average speed is 29.5 mph (47.5 kph). That's why he rides for Health Net and my wife and I do not. That stretch included winning the KOM.



I think what interested me the most about looking at the power file was the difference in the various segments of the race and the clean transition from one to the next. Different duties, stuctured efforts. Quite unlike the stochasic, unorganized nature of my races.

TdG Wheel-Suck Power

From VeloNews:

What kind of power did it take for Health Net-Maxxis rider Frank Pipp to win the KOM jersey in stage 2 of the Tour of Georgia? According to his coach, Frank Overton, it took 874 watts or 12.5 watts/kg for 30 seconds. "Pipp jumped 100 meters before a 90-degree left hand turn (12 secs @ 948w) then gave it full gas for 873 watts for the next 15 seconds, accelerating all the way to the line, " Overton said.



Frank Pipp - 2008 Tour de Georgia

"For the first 60k & 80 minutes of the race, Frank was on break duty and tagged several moves for 309 normalized watts, which is tempo wattage for him.

As soon Justin England went clear, the speed of the peloton settled and Frank sat in the for an easy zone 2 ride of 220 watts for the next 21/2 hours.

Interesting. I'm surprised that it would only take 220 watts (NP, I assume - based on the above NP references) to sit in the TdG peloton for a 2.5-hour period, even if it was a slow section. That's easier than a typical 225-230 w NP, 5-hr Peach Peloton ride, and much easier than our 1.5-hr 275-watt Tuesday Worlds rides.

I'll download some of the WKO+ power files and take a closer look. If I find anything interesting, I'll post it here.

Midyear Review

My 2008 training season started on November 1, so it's half time. With lots of power numbers flying around it can get tough sometimes to see the peleton for the cyclists. I think the clearest way to see long-term progress is by comparing mean maximal power (MMP) charts for two different periods. Below is a MMP chart comparing my MMP for the first 6 months of the 2007 season (dotted line) with my MMP for the first 6 months of this season (solid yellow line).



I've made progress across the board, but my improvement has been greatest for the short (less than 20 seconds) efforts. In that range, I've seen improvements of 130 to 190 watts. For most longer time intervals, my improvement has been in the 20 to 60 watt range.



Below the MMP chart, I have a mean maximal normalized power chart comparing the same periods. For time intervals less than about 50 minutes, I've improved my MMNP by 30 or 40 watts, which is significant. The fact that the increase in MMNP is bigger than the increase in MMP for the same time intervals means that I can recover more quickly than I could one year ago and put in another hard effort. But even out to the 4 and 5 hour ride duratoins, my increase is in the 25 to 30 watt range.

Same Tune, 2nd Verse: Perry-Roubaix 2008

A little moisture made Firetower Road easier to ride this year, but the dirt and wind were still more than I could handle. My power output was much higher than last year, but evidently so was everyone else's.

Here's some 2007-2008 comparison data for those who are interested. This is for the Competitive 35 and under field (I weigh 149 lbs):

My NP for the first 45 minutes of the race in 2007 was 224 watts; in 2008 it was 270 watts. My NP for last 8 minutes prior to losing the group in 2007 was 204 watts (remarkably low, even considering that my FTP was only 235 or 240 at the time). In 2008 my NP for the last 8 minutes before catching the autobus was 301 watts, which makes more sense - that's about 15 watts above my current FTP. I can only hold 4.44 watts/kg for a while before popping.

The climbs were tougher this year, too. Here are my average power numbers (with watts/kg) for the two short climbs on the front part of the course for the first two laps (L is lap, C is climb):

---------L1/C1------- L1/C2--------L2/C1--------L2/C2

2007---298(4.4)-----378(5.6)----233(3.4)-----307(4.5)

2008---371(5.5)-----376(5.6)----347(5.1)------362(5.3)

Albany Georgia Cup Race Data

Bill leads the blue train in the Georgia Cup Albany Crit.

Power graphs with summary data for Albany:

Prologue

Criterium

Road Race

Strain-Gauge Perspective

Mostly the information I get from my power meter just provides a different angle on cycling. It doesn't make the riding and racing better, it just adds data mining to the list of things I enjoy that are associated with cycling.

But the one thing that the Ergomo provides that helps me the most is long-term perspective.

Relatively speaking, I'm no stronger in my group of riders than I was 12 months ago. On a good day, I end up in a strong front group, and on other days I get dropped like a trapeze artist with bad timing. If I had no power meter, I might think that I was no better rider now than I was last February. But the power meter tells me that I'd be wrong. I'm a much better rider now - occaisionally dropping or getting dropped by teammates who are also much better riders than they were last winter.


I know that to be true because today I went to my regular hill repeat spot and did a few 1-minute intervals. I was aiming for 60-seconds at 1.5 times FTP, or 420 watts. I decided to do the first interval based on perceived exertion, not looking at the power meter. My average for the interval was 477 watts - and I didn't kill it - I just pushed steady for 60 seconds.

To put that into perspective, you'd need to look back at a hill repeat session I did in April of 2007 at the same location. On that occaision I did 10 hill repeats, all of them about 40 to 50 seconds long, and all of them averaging between 340 and 380 watts. And I can remember that session. I remember how strong I felt and how I couldn't believe that I was holding 375 watts steady. Now I'm a hundred watts stronger for the same interval session.

While the results make me feel good, they don't guarantee race results. Those come from more than just wattage. And the competition may have power meters that are telling them good things, too.

CTL

This is an overview of my CTL (chronic training load) since Spring 2006, when I started training for bike races:


I read somewhere that for steady, long-term CTL building, you should aim for a CTL each November that equals your prior year's April CTL. Even without specifically trying to do that, I have fit into that pattern over the last two years.

Another interesting item: October was my off month (I rode a little, but didn't train). My CTL constant is set at 42 in Performance Manager, and my current CTL (12-26-07) is 81.6. If I had done a 125TSS workout on October 15th, almost 75 days ago, my CTL would now be 82.1, half a point higher. It's a common misconception that if your CTL constant is set at 42, then only the last 42 days of TSS data will contribute to your current CTL, but that's not true. I believe CTL is calculated using a radioactive decay equation where 42 would be the half-life of the TSS generated in the past. So the older TSS points don't count as much, but they still have an effect. So my October off time is still having an effect on my current CTL.

Strange Time for New Sprint Records

My sprint power:

Old Records: ------Peak-1042w; 1s-1062w; 5s-979w; 10s-880w
Today's numbers: Peak-1149w; 1s-1119w; 5s-1061w; 10s-919w

Either the Thursday 8x15s intervals are having an effect or I have a fresher anaerobic system this time of year because I'm doing mostly aerobic work. Maybe some of both.

Thank you Otter and Badger for serving as carrots on the 1/5 second and 10 second records, respectively. I lost both sprints, but maybe I was close enough for you to hear me breathing for a change.

Six Gap Century power data

Here's my data from Sunday's Six Gap Century in Dahlonega.

Neel’s – AP258, NP260 18:34 3.3mi
Jack’s – AP242, NP259 25:02 5.5mi
Unicoi – AP242, NP261 13:24 2.2mi
Hogpen – AP228, NP238 42:54 6.9mi
Wolfpen – AP228, NP230 20:52 2.8mi
Woody – AP201, NP230 20:52 1.5mi
(AP-average power; NP-normalized power)

Power and elevation graph scaled by distance:

I found the Unicoi power trend interesting. Jake hit the climb hard early and I gradually and very steadily ramped up my effort to finish with him at the top.

Power and elevation graph scaled by time:

September Sprints results

I was skeptical that I could improve my short-interval anaerobic power very much in only 5 weeks, especially at the end of a season where I'd had a fair amount of unstructured short interval work in races and hard group rides. And my 5-week plan didn't include as many sprint intervals as I'd planned to do.

But as the graph below shows, just a few weeks of about two sprint interval sessions per week (8 x 15sec) have resulted in a pretty good uptick in my 30-second, 60-second, and 2-minute max power. I've thought about whether there is another reason for those improvements, but have no other excuse than the sprint intervals. As I've said before, I'm no sprinter, but improvement in those time intervals should help me stay closer to the front in bunch sprints.




Like they say, your body can't do what you don't train it to do, and I've always hated sprint intervals and not done many. I found that the more I did them, the less I disliked them. I think even one sprint interval session a week throughout the season would make a noticeable difference, and they can be done quickly before a longer ride so they don't mess with your schedule very much.

It's also interesting to note that my winter training plan includes L7 (10 to 15-sec sprint) intervals one day per week during the L1-L4 (base) training phase. According to the folks who study this stuff, you can do L7 intervals and if you recover completely between intervals, they won't negatively affect your aerobic adaptation becasue you aren't really stressing your anaerobic metabolism in such a short time, you're just stressing your musculoskeletal systems. But if you try to mix in L5 or L6 intervals during the base training period, your aerobic adaptation will be reduced, so avoid them if possible.

That tells me that the sprint intervals probably aren't helping me through better anaerobic energy system development, but through neurological adaptation. The muscle memory and nerve signal systems are improving, which is the same thing that happens when you start lifting weights after a long layoff and you get big gains in the first few weeks without any muscle growth.

RR power and Crit power

Sometimes the more charts I have to study, the less each of them means to me. If I wanted to boil my long-term cycling training progress down to two numbers, they would be:

1. Functional Threshold Power (FTP) - sustainable power for an hour

2. Crit Normalized Power (CNP) - sustainable power for 35 minutes

The first is well-known. I just invented the second one.

Those two numbers are indicative of my sustainable power in road racing (FTP) and criterium racing (CNP). Here's a chart of how those numbers have increased for me over the past season:

Both numbers showed substantial improvement through the winter and early spring, then plateaued through the summer, and have started trending upwards again. My FTP is now at 280 and my CNP is at about 292. Why the late season increases? Here are some theories as to why the numbers might be going up again:

1. Cumulative effect of entire year of hard training (this one may be the most likely explanation)

2. Delayed effect of huge weekly effort at RAGBRAI in late July (8 weeks, that seems reasonable for adaptation to the effort?)

3. Effect of sprint training that I started in mid-August (unlikely, I think, but possibly a contributor).


Keeping the numbers headed northward is one thing. Next and just as importantly, I have to learn how to use the power more efficiently in races - staying at the front of crits, attacking at the right time in road races, working effectively for teammates, etc.

2007 Training Load

Here's my 2007 CTL chart. I started last November at about CTL=40. CTL is chronic training load, expressed as TTS/day. It's not an average, but a power function with a half-life of 42 days. (The yellow is total stress balance [TSB]. Check out the CTL spike and the TSB valley of doom that I endured for about a week after RAGBRAI in July.)




Anyway, you can see that it took me all winter last year with Peach Peloton rides on weekends (see the little spikes in the blue line from November to February that faded back during the following weeks) and riding the trainer and doing weight workouts on weekdays to get from 40 up to about 65 by the time the season got underway and I started working on some intensity.


This year I plan to use erg files, computrainer racing against others, and more riding during the week to prevent my CTL from dropping below about 70 or so. I'll also keep some intensity included in my weekday workouts. Hopefully, I'll be more prepared for intensity when next season's races start.


Also, I hope to maintain my current FTP of around 278 watts so that the Peach Peloton rides this year will give me an intensity factor of about 0.74 instead of the 0.85 that I got last year. The 0.74 should be more effective in giving me the endurance mileage that I need without requiring me to take so much time for recovery during the early part of each week. (Those numbers assume that my normalized power on Peach Peloton rides will be about 205 watts, like last year. If I work more at the front or if the rides are faster than last year, I might be looking at IF=0.85 again).

Tracking Functional Power

Functional Threshold Power (FTP) is the highest average power you can hold for a 1 hour steady effort. I performed a 1-hour road test for FTP in December 2006 and found it to be 240 watts. I tried again in April and got a result of 268 watts. My next sheduled test was August, but when I attempted the test, I couldn't get through it mentally - I stopped after 20 minutes. I guess it was just one of those days.

The difficulty of accurately measuring FTP on any given day got me thinking. I compared my FTP testing results with my 60-minute best normalized power (NP) for the same period and saw a very strong correlation. So I think I might make the formal FTP test a thing of the past and just monitor my 60 min NP to determin my FTP - it seems to be just as good or better of an indicator that one test on a single day and it uses data from hard training and racing, requiring no training-to-racing conversion factors. (With FTP testing in training, I always threw in a 1.03 factor to account for motivation of racing, etc., and I'm always a little wary of generic factors). So from now on I'll use racing data and keep the factors out of it.

FTP is a good indicator of road racing and TT fitness, but to get a better handle on my crit fitness, I'll also track what I'll call CTP, or Crit Threshold Power. It's nothing more then mean maximal 35-minute NP. It includes more of the anaerobic effort required for short crit races like we see in cat4 races, so it might not track exactly with FTP throughout a season.

As you can see below, my FTP climbed over the winter and early spring, levelling out at about 275 watts, which I think is accurate. My CTP pretty much mirrored FTP except for a jump in the last month, which I attribute to the sprint training I've started to do. I look forward to see where that goes with more work.

One last caveat: in order for this chart to accurately reflect my fitness, I need to make sure to do at least one or two hard 35-minute and 1-hour efforts in each two month period, even during the winter. Do crits exist in January?