This post accompanies a post on the Coggan training levels. Below is a training calculator based on these levels, applied to rowing on the Concept II ergometer. Some caveats are in order. First, Coggan calculated his levels paced on empirical cycling data, not from Concept II ergometer rowing data. The Concept II ergometer may not measure all power (watts) applied during an effort (i.e., the ergometer may miss the power employed on the recovery). Finally, the basis for Coggan's levels is threshold power, which is optimally derived from an hour-long effort (see his discussion here). We use a derivation based on a 20-minute effort; it is assumed that threshold power is 94% of 20-minute power. Read the above article for more discussion of this.
The calculator below is actually my first attempt and it displays the watts associated with pace. I thought some folks might find this second calculator more confusing because as watts increase, the splits decrease (and vice versa). Also, we rowers are more accustomed to using 500m splits instead of watts.
Watts are the basis of both calculators. Both calculators take the 20-min pace and convert it to power (watts). Then the training levels are calculated using percentages of power which are subsequently converted to pace. The calculator below more clearly shows the relationship between pace and power.
The relationship between rowing ergometer pace and power is discussed in many places, e.g., the Physics of Rowing; it is a non-linear relationship such that you must apply 8 times as much power to go twice as fast. So, for example, rowing at 4:00 pace uses about 25 watts on a Concept II machine, while rowing at 2:00 pace uses about 200 watts.
Showing posts with label calculator. Show all posts
Showing posts with label calculator. Show all posts
Training Levels: Coggan
Training levels (aka categories or zones) are guidelines of intensity,
heart rate, percent of power at lactate threshold, or percent of VO2max
intensity, etc that help us figure out what kinds of training we should
be doing to elicit certain physiological benefits. There are many training schemas, but one that is particularly interesting to me is that of Andrew Coggan, a competitive cyclist
and a published exercise physiologist. This schema uses power (watts).
The most accessible version of his training levels conception appears in this power training levels article. You can read about it in more detail in the book, Training and Racing With a Power Meter as well as frequently in the Wattage training forum.
Can his training levels, which are based on power (watts) on a bicycle, be adapted to the Concept II rowing machines, which also can display power? I believe this may be possible and I have created a training level calculator to help.
Some key points in the Coggan approach
The upside
Power on the bicycle is typically calculated by measuring torque with strain gauges in one of several places and combining that with angular velocity. If your eyes are about to glaze over with this terminology, don't despair: the bottom line is that if you are doing something to the pedals, a watt-meter on a bike will likely measure it.
By comparison, the rowing ergometer measures power by what happens at the flywheel (source), which is to say, it measures what happens on and as a result of the drive. You pull the handle, which pulls the chain, which pulls the flywheel and that is the power that is measured. It does not measure the amount of work done - however small - on the recovery. Thus, watts on the rowing machine may understate power. Just how many watts are missed depends on various factors, including rower's mass, distance moved by the rower's center of gravity, and most importantly, stroke rate. Carl Douglas, boat designer and inveterate tinkerer of things physical, spent some time calculating how many watts might be missed and you can read that discussion here. If you accept his assumptions and calculations, a rower might lose anywhere from 5 to 27 watts with stroke rates between 20 and 30. However, at a stroke rate of 40, you might lose up to 100 watts.
The power you can maintain in all-out effort (time-trial or "test") for 60-minutes is deemed to be a good measurement by many exercise physiologists of lactate threshold (LT) power. In Threshold power: what is it, why is it important, and how do I measure it? Coggan suggests that an all-out 1 hour effort is the best way to ascertain "threshold power." According to Coggan. "Power at lactate threshold (LT) is the most important physiological determinant of endurance cycling performance..." He adds more decisively:
Of course, you can also have your lactate threshold and power at lactate threshold measured at labs such as this one at UCDavis, but they may involve a bit of blood letting. The hour-power test may seem more appealing.
Can you derive "hour power" from some shorter test?
An amazing amount of time and energy has gone into figuring out a shorter alternative to the 60-minute all-out test, particularly on the wattage cycling forum. Authors like Joe Friel and Eddie Monier favor a critical power duration curve, such that you test some representative times and derive others. So, for example, if you know your "critical" power at 6 minutes and 12 minutes, you can likely figure out a reasonable approximation of your 60-minute power. Below is an example of such a curve.
Following this approach, many cyclists (as expressed in the wattage forum) have found that 60-minute power is somewhere between 93% and 97% of 20-minute average power. Many just settle for 95%, acknowledging that an exact number may not be that important (and many are using software that will help them hone in on better numbers).
Here is an example of how you might figure out your threshold power using a 20-minute piece. If your average power in watts for 20-minutes is 200, then your average power for 60 minutes might be 5% less or 190 watts.
Does this system work for rowers?
The answer is not so clear. I created an Excel spreadsheet a few years ago to try this out. More recently, I created a javascript level calculator. You can enter your 20-minute average 500m split and the calculator derives your training levels based on 94% of the power associated with this split. My own experience is that the lower intensity levels seem to represent something fairly reasonable, but when you get to level 5 and 6, the prescribed pace range actually lags what I would expect. In other words, I would expect to have to go harder. And, given Carl Douglas' point about the ergometer understating watts, particularly at higher rates, one would expect the intensities to be too hard relative to the cycling-derived power levels. However, that does not seem to be the case.
How does the Coggan arrangement stack up against, say, Royle's?
Coggan's descriptive levels and Royle's prescriptive categories are different in a few regards, but similar as well. The most obvious difference is that Royle's categories go in the opposite direction (intensity increases as the category number decreases) from Coggan's levels (intensity increases as the number level increases).
A fundamental difference between the Coggan and Royle approaches is the expected physiological adaptations. For instance, in Royle's schema, "Cat III rowing increases VOmax." (from November 2002 Technical Tip). You get the sense that if you want to develop VO2Max, Cat III is the only category to do this. In fact, the categories seem to be non-overlapping and highly specific. Coggan, on the other hand, shows in his Expected physiological/performance adaptations (Table 2), that you get VO2max benefits from levels 2, 3, 4, 5, and 6, with the most coming from level 5.
Royle suggests you develop increased capillarization and greater numbers of mitochondria at the lower intensities (Cat V and VI). This is accompanied with admonition that "Going too fast at the lower rates denies your body the opportunity to develop optimum capillary and mitochondria density" (source), while Coggan suggests level 4 (threshold) and level 5 (VO2Max intensity) as the training intensities most associated with these adaptations (source). In other words they seem to be at opposite ends of the intensity spectrum on this apparently important issue. This basic disagreement deserves further examination in another post.
My adaptation of Coggan's levels as shown in the levels calculator and the training category calculator ala Marlene Royle are both based on a 20-minute piece, so it is easy to compare Royle's prescribed training category pace with the levels as derived from Coggan. CAVEAT: I think it's important to note that the levels calculator is experimental and based on a somewhat arbitrary calculation (94% of watts of a 20-minute piece to signify threshold power). I do not claim this represents Coggan's thinking or his approach. In fact, he might well tell you that you should row for an hour. Since I know few rowers who will do this, we'll just go with the experiment and try to disassociate this effort with Coggan himself, while giving him credit for many of the underlying ideas. Finally, he would label these levels as descriptive rather than prescriptive. So, when I say "ala Coggan" this is what I mean.
Phew! With that caveat aside, I looked first at the respective level or category targeting VO2max improvement: Royle's Cat III and Coggan's level five. I compared a 20-minute 500m split of 1:51.0 in both schemas. Royle's system suggests a Cat III split of 1:49, while Coggan's level five--as represented in the levels calculator--suggests a range from 1:46.6 - 1:51.1. In effect, the results are very similar. The example workouts aren't particularly different either. Both seem to like 5 x 5-minutes and related.
For lactate threshold development, Royle calls for Cat IV and Coggan calls for level four. Royle's system suggests a workout pace of 1:53, while the level calculator suggests a range between 1:51.5 - 1:56.9. Again, that seems remarkably similar - Royle's number is smack dab in the middle of the level calculator's range. However, when you compare workouts, it is a different matter. Royle's suggested workout of 3 x 20 minute intervals is way, way too hard - essentially impossible - for myself and others I know. Several people who have been employing Royle as a coach have corroborated this. She also lists 4 x 10 and 1 x 30-minute workouts (see "Workouts: Category IV Anaerobic Threshold Training") . Coggan's recommended threshold workouts include intervals or repeats in the 10-30-minute duration, with a common workout being 2 x 20-minutes. These workouts, with a 5.5 second 500m split range, seem considerably more plausible.
In conclusion, the Coggan training levels deserve further consideration, particularly for those training on a rowing ergometer. This training schema affords a rational, science-based arrangement that, while designed for cycling, may have applications in rowing.
The most accessible version of his training levels conception appears in this power training levels article. You can read about it in more detail in the book, Training and Racing With a Power Meter as well as frequently in the Wattage training forum.
Can his training levels, which are based on power (watts) on a bicycle, be adapted to the Concept II rowing machines, which also can display power? I believe this may be possible and I have created a training level calculator to help.
Some key points in the Coggan approach
- the power that you use in an all-out hour effort is a logical choice for deriving other training levels because it "integrates VO2max, the percentage of VO2max that can be sustained for a given duration, and ... efficiency"
- Physiological responses to training "fall on a continuum", so that the adaptations that occur from one intensity blur with those of another intensity. This shows up particularly in the chart of physiological benefits accrued from different intensity exercise.
The upside
- Physiological benefits elicited at different training intensities are displayed in easy-to-read chart. Coggan is quick to point out that these are descriptive levels not prescriptive.
- Sample workouts give you an idea of intensity, duration, and frequency.
- Supported by research. This is evidence-based training advice and while research isn't cited on the web page, it is abundant in the power training forum and in the book.
- Designed for cyclists. Descriptions like "easy spinning" or "just above TT effort" may not easily translate into rowing intensity. However, Coggan provides a perceived exertion rating (Borg Scale), as well as a heart rate reference (see below), so you can transmogrify from that.
- Figuring out your training zones is optimally based on an hour effort. Imagine doing an all-out hour-long piece on the rowing ergometer! We have a hard enough time doing a 20-minute test! Cyclists must be more patient, tolerant (or stupid) than rowers.
- Heart rate zones are provided as a percentage of HR at threshold power (your heart rate at a pace you could maintain for an hour). Coggan is not a big fan of heart rate as a training tool, because it is susceptible to many other variables (heat, emotional state, caffeine and other drugs, etc).
- Training level power numbers are provided as a percentage of hour power. In other words, you need to know your "hour power" to optimally calculate your training levels. It turns out that many people have figured out how to derive their levels with 20-minute all out efforts. More on this later.
- Power (as in watts) is the main focus. For rowers used to 500m splits, this may require some adaptation, but power is available at the click of a button on the ergometer.
Power on the bicycle is typically calculated by measuring torque with strain gauges in one of several places and combining that with angular velocity. If your eyes are about to glaze over with this terminology, don't despair: the bottom line is that if you are doing something to the pedals, a watt-meter on a bike will likely measure it.
By comparison, the rowing ergometer measures power by what happens at the flywheel (source), which is to say, it measures what happens on and as a result of the drive. You pull the handle, which pulls the chain, which pulls the flywheel and that is the power that is measured. It does not measure the amount of work done - however small - on the recovery. Thus, watts on the rowing machine may understate power. Just how many watts are missed depends on various factors, including rower's mass, distance moved by the rower's center of gravity, and most importantly, stroke rate. Carl Douglas, boat designer and inveterate tinkerer of things physical, spent some time calculating how many watts might be missed and you can read that discussion here. If you accept his assumptions and calculations, a rower might lose anywhere from 5 to 27 watts with stroke rates between 20 and 30. However, at a stroke rate of 40, you might lose up to 100 watts.
The power you can maintain in all-out effort (time-trial or "test") for 60-minutes is deemed to be a good measurement by many exercise physiologists of lactate threshold (LT) power. In Threshold power: what is it, why is it important, and how do I measure it? Coggan suggests that an all-out 1 hour effort is the best way to ascertain "threshold power." According to Coggan. "Power at lactate threshold (LT) is the most important physiological determinant of endurance cycling performance..." He adds more decisively:
LT - especially when expressed as a power output...is the single most important physiological determinant of performance in events ranging from as short as a 3 km pursuit to as long as a 3 week stage race. Just as importantly...this parameter provides a physiologically sound basis around which to design any power meter-based training program.In a bit of rowing corroboration, Stephen Seiler, rower and exercise physiologist, emailed me to say that a 60-minute effort on the rowing machine is the best way to ascertain lactate threshold intensity for rowers.
Of course, you can also have your lactate threshold and power at lactate threshold measured at labs such as this one at UCDavis, but they may involve a bit of blood letting. The hour-power test may seem more appealing.
Can you derive "hour power" from some shorter test?
An amazing amount of time and energy has gone into figuring out a shorter alternative to the 60-minute all-out test, particularly on the wattage cycling forum. Authors like Joe Friel and Eddie Monier favor a critical power duration curve, such that you test some representative times and derive others. So, for example, if you know your "critical" power at 6 minutes and 12 minutes, you can likely figure out a reasonable approximation of your 60-minute power. Below is an example of such a curve.
Source: Eddie Monnier Critical Power
Following this approach, many cyclists (as expressed in the wattage forum) have found that 60-minute power is somewhere between 93% and 97% of 20-minute average power. Many just settle for 95%, acknowledging that an exact number may not be that important (and many are using software that will help them hone in on better numbers).
Here is an example of how you might figure out your threshold power using a 20-minute piece. If your average power in watts for 20-minutes is 200, then your average power for 60 minutes might be 5% less or 190 watts.
Does this system work for rowers?
The answer is not so clear. I created an Excel spreadsheet a few years ago to try this out. More recently, I created a javascript level calculator. You can enter your 20-minute average 500m split and the calculator derives your training levels based on 94% of the power associated with this split. My own experience is that the lower intensity levels seem to represent something fairly reasonable, but when you get to level 5 and 6, the prescribed pace range actually lags what I would expect. In other words, I would expect to have to go harder. And, given Carl Douglas' point about the ergometer understating watts, particularly at higher rates, one would expect the intensities to be too hard relative to the cycling-derived power levels. However, that does not seem to be the case.
How does the Coggan arrangement stack up against, say, Royle's?
Coggan's descriptive levels and Royle's prescriptive categories are different in a few regards, but similar as well. The most obvious difference is that Royle's categories go in the opposite direction (intensity increases as the category number decreases) from Coggan's levels (intensity increases as the number level increases).
A fundamental difference between the Coggan and Royle approaches is the expected physiological adaptations. For instance, in Royle's schema, "Cat III rowing increases VOmax." (from November 2002 Technical Tip). You get the sense that if you want to develop VO2Max, Cat III is the only category to do this. In fact, the categories seem to be non-overlapping and highly specific. Coggan, on the other hand, shows in his Expected physiological/performance adaptations (Table 2), that you get VO2max benefits from levels 2, 3, 4, 5, and 6, with the most coming from level 5.
Royle suggests you develop increased capillarization and greater numbers of mitochondria at the lower intensities (Cat V and VI). This is accompanied with admonition that "Going too fast at the lower rates denies your body the opportunity to develop optimum capillary and mitochondria density" (source), while Coggan suggests level 4 (threshold) and level 5 (VO2Max intensity) as the training intensities most associated with these adaptations (source). In other words they seem to be at opposite ends of the intensity spectrum on this apparently important issue. This basic disagreement deserves further examination in another post.
My adaptation of Coggan's levels as shown in the levels calculator and the training category calculator ala Marlene Royle are both based on a 20-minute piece, so it is easy to compare Royle's prescribed training category pace with the levels as derived from Coggan. CAVEAT: I think it's important to note that the levels calculator is experimental and based on a somewhat arbitrary calculation (94% of watts of a 20-minute piece to signify threshold power). I do not claim this represents Coggan's thinking or his approach. In fact, he might well tell you that you should row for an hour. Since I know few rowers who will do this, we'll just go with the experiment and try to disassociate this effort with Coggan himself, while giving him credit for many of the underlying ideas. Finally, he would label these levels as descriptive rather than prescriptive. So, when I say "ala Coggan" this is what I mean.
Phew! With that caveat aside, I looked first at the respective level or category targeting VO2max improvement: Royle's Cat III and Coggan's level five. I compared a 20-minute 500m split of 1:51.0 in both schemas. Royle's system suggests a Cat III split of 1:49, while Coggan's level five--as represented in the levels calculator--suggests a range from 1:46.6 - 1:51.1. In effect, the results are very similar. The example workouts aren't particularly different either. Both seem to like 5 x 5-minutes and related.
For lactate threshold development, Royle calls for Cat IV and Coggan calls for level four. Royle's system suggests a workout pace of 1:53, while the level calculator suggests a range between 1:51.5 - 1:56.9. Again, that seems remarkably similar - Royle's number is smack dab in the middle of the level calculator's range. However, when you compare workouts, it is a different matter. Royle's suggested workout of 3 x 20 minute intervals is way, way too hard - essentially impossible - for myself and others I know. Several people who have been employing Royle as a coach have corroborated this. She also lists 4 x 10 and 1 x 30-minute workouts (see "Workouts: Category IV Anaerobic Threshold Training") . Coggan's recommended threshold workouts include intervals or repeats in the 10-30-minute duration, with a common workout being 2 x 20-minutes. These workouts, with a 5.5 second 500m split range, seem considerably more plausible.
In conclusion, the Coggan training levels deserve further consideration, particularly for those training on a rowing ergometer. This training schema affords a rational, science-based arrangement that, while designed for cycling, may have applications in rowing.
VO2Max % Calculator
If you read much training literature, you will likely come across training prescriptions like "steady state efforts
at 65-75% of VO2max lasting 45 to 120 minutes to repeated 'Anaerobic Threshold work' at 80-90% of VO2max for 15 to 30 minutes." (Source: Stephen Seiler) And exercise physiology research is replete with references to VO2max like: "the best single predictor of 2000 m rowing ergometer performance was power at VO(2max)."
Most of us have not been lab-tested to ascertain our VO2max (fyi, that's peak oxygen consumption, how much oxygen we actually use), and therefore we probably don't know what 100% of VO2max is or 90% or 80%. These references are relatively meaningless to us.
What does 70%, 80%, 90% of VO2max intensity mean for me?
Fortunately, some researchers like Stephen Seiler, a rower, have figured out that VO2max intensity is roughly associated with the power (watts) during a 2k all out effort on the rowing ergometer. Seiler, in an email conversation, wrote: "Bottom line use 2k power as VO2max power..." Separately, Steve Ingham, an exercise physiology researcher, wrote to me: "our observations suggest that the rowers do reach VO2max when they perform 2000m ergometer tests." Finally, Fritz Hagerman, noted rowing researcher, also emailed me with a similar conclusion. These statements, which in all cases are probably the result of looking at a lot of empirical data, do not, in themselves, constitute research results showing that a 2000m ergometer test is a proxy for VO2max intensity. I'm hoping that Steve Ingham will pursue that line of inquiry, and I think he may already have the data. In the mean time, I have cooked up a calculator based on just this notion.
Here's how it works:
Questions for the future:
Most of us have not been lab-tested to ascertain our VO2max (fyi, that's peak oxygen consumption, how much oxygen we actually use), and therefore we probably don't know what 100% of VO2max is or 90% or 80%. These references are relatively meaningless to us.
What does 70%, 80%, 90% of VO2max intensity mean for me?
Fortunately, some researchers like Stephen Seiler, a rower, have figured out that VO2max intensity is roughly associated with the power (watts) during a 2k all out effort on the rowing ergometer. Seiler, in an email conversation, wrote: "Bottom line use 2k power as VO2max power..." Separately, Steve Ingham, an exercise physiology researcher, wrote to me: "our observations suggest that the rowers do reach VO2max when they perform 2000m ergometer tests." Finally, Fritz Hagerman, noted rowing researcher, also emailed me with a similar conclusion. These statements, which in all cases are probably the result of looking at a lot of empirical data, do not, in themselves, constitute research results showing that a 2000m ergometer test is a proxy for VO2max intensity. I'm hoping that Steve Ingham will pursue that line of inquiry, and I think he may already have the data. In the mean time, I have cooked up a calculator based on just this notion.
Here's how it works:
- Let's say my 2000m time is 6:53.0 (it used to be...). I enter this in the calculator below and hit the "Calculate" button.
- This calculates my watts and 500m splits for various intensities, e.g., 100% VO2max intensity for me is roughly 318 watts and a 500/m split of 1:43.3. Is this an accurate estimate of my VO2max? I don't have good evidence that it is; take it with a generous dose of salt. Like my 2K time...
Questions for the future:
- How does this notion (2000m pace or power as proxy for VO2max intensity) compare with other proxies like heart rate reserve?
- How individually variable is, say, 80% VO2max with physiological measurements like lactate? In other words, is one person's 80% VO2max below lactate threshold, while another's 80% VO2max is well above lactate threshold? And, what consequences follow?
Cat Calculator a la Royle
Enter your 20-minute average 500m pace at the top and click the Calculate button at the bottom and your calculated category 500m splits will be displayed. Other fields in the top-half of the calculator can be edited.
This training category calculator is based on some of the training notions of Marlene Royle and others as stated in articles which appear in the Craftsbury Sculling Center's technical tips section. The article that summarizes the categories and their derivation and benefits is called "Performance-Based Training Paces: How Fast or Slow to Row?".
This is my experience. What's yours?
This training category calculator is based on some of the training notions of Marlene Royle and others as stated in articles which appear in the Craftsbury Sculling Center's technical tips section. The article that summarizes the categories and their derivation and benefits is called "Performance-Based Training Paces: How Fast or Slow to Row?".
Roughly equivalent zones appear also in Volker Nolte's Rowing Faster
in a chapter on Improving Anaerobic Threshold by Wolfgang Fritsch.
The women's racing team at the Ashland Rowing Club uses these training categories to guide their training. It seems to provide a useful framework for structuring workouts and monitoring progress. Your experience may vary.
The women's racing team at the Ashland Rowing Club uses these training categories to guide their training. It seems to provide a useful framework for structuring workouts and monitoring progress. Your experience may vary.
Several folks I know who subscribe to Royle's training advice have difficulty with the Cat
IV "anaerobic threshold" workout of "3 x 20-minutes with 5-7 minutes rest [in] between at stroke rate 24." This is certainly beyond my capability. If my average 500/m pace for
20-minutes all-out is 1:50.0, then my Cat IV 500/m average is 1:52.0. I cannot row 3 x 20 minutes at that pace. Realistically, I
might make it through one and a half intervals, but not two and certainly not a third. For what it's worth, I feel very gratified to be able to do 2 x 20 at a pace of 1:55.
On the other hand, the Cat III intervals seem on the easy side. For me, based on the 1:50 split time for 20-minutes, that would be 1:48, which would be quite comfortable in the recommended 5 x 5 minute intervals (same source as above). These are supposed to be "intense" but, in fact, they would be a breeze compared to the suggested 3 x 20-minute intervals.
On the other hand, the Cat III intervals seem on the easy side. For me, based on the 1:50 split time for 20-minutes, that would be 1:48, which would be quite comfortable in the recommended 5 x 5 minute intervals (same source as above). These are supposed to be "intense" but, in fact, they would be a breeze compared to the suggested 3 x 20-minute intervals.
This is my experience. What's yours?
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