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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