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 VO2max. Show all posts
Showing posts with label VO2max. 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?
Detraining: Fitness is Fleeting
“De-Train, boss, de-train.”
Remember the Herve Villechaize character, Tattoo, in “Fantasy Island” alerting Ricardo “Corinthian Leather” Montalbán to the arriving plane. Ok, maybe you don’t and kudos to you. Still, I like the notion of Tatoo announcing to all rowers in November: "De-Train, De-Train", and then all the rowers would sit back, sip umbrella drinks and enjoy the detraining vacation of their choice, maybe on Fantasy Island.
Detraining is the word exercise physiologists use to describe what happens when you stop training for some period of time; it’s the reversal of adaptations to exercise. It likely happens to many of us after the end of our competitive seasons, when we think we should take some time off.
How much fitness is lost and over what period of time?
One of the major tenets of exercise physiology-- the reversibility principal--says that even for athletes with years of training, adaptations can be lost. My exercise physiology text book states that "only 1 or 2 weeks of detraining significantly reduces both metabolic and exercise capacity." And, after 3 weeks of detraining (less than the time between Thanksgiving and Christmas) things get markedly worse. The authors (McArdle, Katch and Katch) provide a dismal laundry list of fitness losses:
You can imagine that it is difficult for scientists to find competitive athletes who take much time off, but occasionally researchers apparently find someone who is either injured and wants to get back or someone who is contemplating retirement and then reconsiders after some time off. The researchers poke, prod and measure these poor people and get some interesting data. These "case studies" are not the large subject studies that scientists prefer, but they can be illuminating.
One such study involves a single Olympic caliber rower. The detraining and retraining of an elite rower: a case study shows an example of a loss of VO2max (8% drop), this after 8 weeks of inactivity following the Sydney Olympic games.
Possibly more tangible for readers here might be the 25% drop in power this rower experienced on the Concept II ergometer at "reference blood lactate concentrations". The reference points are typically at 2 and 4 millimoles of lactate, the latter of which is considered by many to be the lactate threshold (a subject for another post). Without knowing the meaning of this last phrase, you can still figure out that this rower experienced a huge loss of power. In his case, the 25% drop happens to be 100 watts. This means that at full fitness, he was pulling 400 watts or roughly a 1:35/500meter split. A 25% decrease in power would translate to 300 watts (400-100) and a more pedestrian (!) 1:45/500meter split. That's a significant difference.
OK, but how long does it take to regain lost fitness?
The last study is interesting for the amount of VO2max lost and for the loss in power on the rowing ergometer, but it is particularly interesting because the rower in question decided to return to training and continued with physiology testing. While he recovered much of his fitness quite quickly, it took approximately 20 weeks to regain what he had lost in just 8 weeks. The researchers summarized:
Most of us are not elite athletes, though, so we wonder what would happen to us. Here is an example of detraining and retraining that may be closer to our own experience. In this case study, the subject is a 49-year old, competitive masters level cyclist who breaks her clavicle. Conveniently for us and the researchers, she has some physiology testing 2 days before getting into that accident. She is off the bike for 32-days and then resumes training. It takes her approximately 6 weeks to return to pre-accident fitness, although her peak power output takes 72 days to re-establish.
The time course of retraining appears, in general, to take longer than the detraining. Take a month off and it might take you two to get fully back in shape.
What is the least amount of training one can do to maintain fitness?
So, you want to train a bit less, but you're not willing to lose all that hard-earned fitness.
A study of runners demonstrated that gains in VO2max over a 10-week period could be maintained by training as little as 2 days a week, for 40-minutes each time, as long as the intensity was high enough.
A study titled "Reduced training maintains performance in distance runners" reduced training volume of elite runners by 70% for 3 weeks, but included workouts at an intensity of close to 95% of VO2max to maintain fitness.
However, a later study by some of the same researchers diminished not only the volume of training but also the intensity, such that no training was executed above 70% of VO2max. In this case, endurance performance dropped even though some metrics such as VO2max remained unchanged. The authors write:
What about on the water rowing intensity for maintaining aerobic capacity (VO2max)?
I can think of a way to calculate on the water intensities (e.g., heart rate) but I think it is too fraught with potential inaccuracies to be worthwhile. More on that in another post.
Other questions:
Remember the Herve Villechaize character, Tattoo, in “Fantasy Island” alerting Ricardo “Corinthian Leather” Montalbán to the arriving plane. Ok, maybe you don’t and kudos to you. Still, I like the notion of Tatoo announcing to all rowers in November: "De-Train, De-Train", and then all the rowers would sit back, sip umbrella drinks and enjoy the detraining vacation of their choice, maybe on Fantasy Island.
How much fitness is lost and over what period of time?
One of the major tenets of exercise physiology-- the reversibility principal--says that even for athletes with years of training, adaptations can be lost. My exercise physiology text book states that "only 1 or 2 weeks of detraining significantly reduces both metabolic and exercise capacity." And, after 3 weeks of detraining (less than the time between Thanksgiving and Christmas) things get markedly worse. The authors (McArdle, Katch and Katch) provide a dismal laundry list of fitness losses:
- VO2Max declines by 8%
- Lactate threshold drops by 7%
- Heart stroke volume decreases by 10%
- Plasma volume diminishes by 12%
- Capillary density drops by 7%
- Oxidative enzyme capacity is down by 29%
- Muscle glycogen synthesis drops by 29%
- Time to fatigue is 10% sooner.
"VO2max was the best single predictor of the velocity for the 2000 m time-trial".A study of "highly trained runners and cyclists" showed a 7% decline in VO2max in just 12 days and 14% decline in 56 days (see graphic below). I had to include this because I spent time making the chart. It is sort of redundant, but reinforces the point about a loss in VO2max.
Adapted from Coyle et al. J Appl Physiol.1984;
57:
1857-1864
You can imagine that it is difficult for scientists to find competitive athletes who take much time off, but occasionally researchers apparently find someone who is either injured and wants to get back or someone who is contemplating retirement and then reconsiders after some time off. The researchers poke, prod and measure these poor people and get some interesting data. These "case studies" are not the large subject studies that scientists prefer, but they can be illuminating.
One such study involves a single Olympic caliber rower. The detraining and retraining of an elite rower: a case study shows an example of a loss of VO2max (8% drop), this after 8 weeks of inactivity following the Sydney Olympic games.
Possibly more tangible for readers here might be the 25% drop in power this rower experienced on the Concept II ergometer at "reference blood lactate concentrations". The reference points are typically at 2 and 4 millimoles of lactate, the latter of which is considered by many to be the lactate threshold (a subject for another post). Without knowing the meaning of this last phrase, you can still figure out that this rower experienced a huge loss of power. In his case, the 25% drop happens to be 100 watts. This means that at full fitness, he was pulling 400 watts or roughly a 1:35/500meter split. A 25% decrease in power would translate to 300 watts (400-100) and a more pedestrian (!) 1:45/500meter split. That's a significant difference.
OK, but how long does it take to regain lost fitness?
The last study is interesting for the amount of VO2max lost and for the loss in power on the rowing ergometer, but it is particularly interesting because the rower in question decided to return to training and continued with physiology testing. While he recovered much of his fitness quite quickly, it took approximately 20 weeks to regain what he had lost in just 8 weeks. The researchers summarized:
"These results show that detraining in the elite athlete can be pronounced, with rapid improvements upon retraining which slow, so that retraining takes considerably longer to achieve than detraining did."This result--that retraining takes longer than the detraining--has been repeated elsewhere to some extent, but with variation.
Most of us are not elite athletes, though, so we wonder what would happen to us. Here is an example of detraining and retraining that may be closer to our own experience. In this case study, the subject is a 49-year old, competitive masters level cyclist who breaks her clavicle. Conveniently for us and the researchers, she has some physiology testing 2 days before getting into that accident. She is off the bike for 32-days and then resumes training. It takes her approximately 6 weeks to return to pre-accident fitness, although her peak power output takes 72 days to re-establish.
The time course of retraining appears, in general, to take longer than the detraining. Take a month off and it might take you two to get fully back in shape.
What is the least amount of training one can do to maintain fitness?
So, you want to train a bit less, but you're not willing to lose all that hard-earned fitness.
A study of runners demonstrated that gains in VO2max over a 10-week period could be maintained by training as little as 2 days a week, for 40-minutes each time, as long as the intensity was high enough.
"it is possible to maintain the increased VO2max for at least 15 wk by training at high intensity for 2 d/wk or 4 d/wk"Another study, with the same initial training protocol (10 weeks of 40-minutes a day) tested a reduction in training duration (as oppposed to frequency). After the first 10-weeks of training, participants were put in two training groups, one that trained for only 26-minutes a day, and one that trained for only 13-minutes a day. Remarkably, the authors found that:
"it is possible to maintain almost all of the performance increases with up to a two-thirds reduction of training duration"A study of swimmers showed that training just 3-days a week was sufficient to maintain aerobic capacity (VO2max).
A study titled "Reduced training maintains performance in distance runners" reduced training volume of elite runners by 70% for 3 weeks, but included workouts at an intensity of close to 95% of VO2max to maintain fitness.
However, a later study by some of the same researchers diminished not only the volume of training but also the intensity, such that no training was executed above 70% of VO2max. In this case, endurance performance dropped even though some metrics such as VO2max remained unchanged. The authors write:
"It is concluded that aerobic capacity was maintained in these runners, despite the combined reduction in training volume and intensity. However, it appears that training intensity during RT (reduced training) is important for the maintenance of 5 km running performance."So, what do we make of all of this?
- If you take time off--more than a couple of weeks(?)--you risk losing some fitness. This shows up particularly in a decreased VO2max, which is clearly important to rowing performance.
- You can maintain VO2max and still substantially reduce training frequency and volume, but you will need to include some higher intensity workouts.
- 70% of VO2max intensity was the lowest intensity to maintain VO2max. Other studies used 80-95% of VO2max intensity to maintain VO2max. Workout durations varied.
- VO2max is only one fitness metric. Clearly if you reduce training duration and frequency, you will lose endurance if not other aspects of fitness.
What about on the water rowing intensity for maintaining aerobic capacity (VO2max)?
I can think of a way to calculate on the water intensities (e.g., heart rate) but I think it is too fraught with potential inaccuracies to be worthwhile. More on that in another post.
Other questions:
- If you get sick and miss training, what is the best way to resume?
- Does cross-training (running, xc skiing, or cycling) help maintain rowing VO2max or is it activity-specific?
- Assuming one just wants to maintain VO2max, how long and how frequent should one perform an 80% VO2max intensity workout? 20 minutes once a week?
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