Is 2,000-meter Rowing Aerobic or Anaerobic?

Is 2,000-meter rowing aerobic or anaerobic? Modern research puts an all-out 2,000-meter row or erg between 77-88% aerobic and 12-23% anaerobic. However, this simple answer isn’t the end of the story. In this article, we’ll cover some of the research behind the aerobic and anaerobic breakdown, then we’ll discuss what this actually means at a physiological level, how energy system use is determined, and why this matters for rowing performance. There are key takeaways from this research to get the most out of each energy system and mode of training, between erging, rowing, cross-training, and strength training.

According to modern research, a 2,000-meter rowing race is between 77-88% aerobic and 12-23% anaerobic. We suspect that the variation exists primarily due to different study populations. Energy system use is determined by intensity and duration of exercise. The shorter the duration, or the higher the intensity, the greater the proportional contribution from the anaerobic system. We’ll see in the research articles that faster times tend to be more anaerobic than slower times. Although no research exists on other distances, we would expect a 1km rowing race to be more anaerobic (Ed McNeely suggests up to 50-60% in “Rowing Faster”), and a 6km race to be more aerobic. Below are main takeaways from modern research articles on energy system use in 2km rowing and erging.

Aerobic and Anaerobic Rowing Research

If you look at “classic texts” of rowing training, you’ll often see much higher anaerobic values. Research from the 1970s and the 1980s typically shows around 30% anaerobic for male rowers, and up to 40% for female rowers. When we look at the methods sections for these studies, we see three main reasons for this. First, female rowers raced 1km races until the 1988 Summer Olympics, so research on female rowers before 1990 skews anaerobic. The second reason is early ergometer design, which relates to the third reason of study methods. The Concept2 ergometers that we know and love, with their air resistance system and calibrated time-and-distance metrics weren’t invented until the early 80s, and weren’t widely available and standard in boathouses and research practices until the early 90s. The Pre-Concept2 Gjessing ergometers featured a mechanical fixed resistance, giving a constant load per stroke (video in action). Early ergs also had no digital monitor, or distance-per-stroke calibration, so researchers of this era typically used a set time of 6 minutes for evaluation of rowers. This is likely more representative of a 1500-meter row, which also skews the values anaerobic. We rarely use 30-year old research for a rigorous investigation anyway, but it’s even less useful to us now, given the vast differences in equipment and study design compared to modern rowing. We also have to be careful with research of the 1990s, which often cites earlier research from the 1970s and 1980s.

We have just three studies from the modern era.

Study	Study Population	Average 2km time	Aerobic %	Anaerobic %
Pripstein et al. (1999)	16 competitive female rowers	Static erg: 7.5 minutes	88%	12%
De Campos Mello et al. (2009)	8 competitive male rowers, tested in three different conditions	Static ergs: 6.75 minutes	84%	16%
		Dynamic ergs: 6.75 minutes	84%	16%
		On-water single scull: 8.5 minutes	87%	13%
Martin and Tomescu (2017)	16 elite male rowers	Static erg: 6.1 minutes	77%	23%

This research offers us the general trend that a longer duration of race results in proportionately greater aerobic energy system contribution. Each of these studies is in need of replication, to determine if the variable results are simply the effect of a shorter race time, or if there are differences between individuals in the study populations, gender differences between studies, or other methodological variables at play.

Quick Overview of Energy Systems

The simple answer of “is rowing aerobic or anaerobic” still doesn’t tell us what to do with that information. Let’s dive in a little deeper and put this information into practice, beginning with a crash course on energy system physiology. I’ve summarized the following from Jay Hoffman’s “Physiological Aspects of Sport Training and Performance” textbook (2nd ed., 2014).

The goal of all energy systems is to produce the adenosine triphosphate molecule (ATP). Breaking ATP down releases energy. The body stores limited ATP readily available for the muscular system, so energy systems are constantly at work to generate more ATP and have more energy available.

The phosphagen system powers high intensity outputs from 0-30 seconds. Glycolysis contributes up to 2-3 minutes of high intensity output in highly trained athletes. The aerobic system fuels the majority of output beyond 2-3 minutes. The aerobic system is the one rowers are most familiar with, so I’ll keep it brief. The aerobic system is an oxidative energy source, meaning that it uses oxygen to produce ATP. Aerobic production cannot keep up with high ATP demand during high intensity output, but it can fuel longer duration outputs at lower intensities by drawing from stored fat and carbohydrates. Aerobic energy primarily comes from carbohydrates during prolonged exercise, while at rest the body will use mostly stored fat.

The phosphagen and glycolytic systems are referred to together as the anaerobic system, because neither energy pathway requires oxygen to create ATP. The phosphagen system stores ATP and creatine phosphate as the first energy system available. This provides energy for high intensity, very short duration outputs. Anaerobic glycolysis is the next energy system, which breaks down glucose to create ATP. This sounds great–ATP created quickly and without oxygen–but the end result of glycolysis is decreased muscle pH and accumulation of metabolites implicated in fatigue. The traditional theory is that glycolysis produces pyruvic acid, which is converted to lactic acid, and increases in lactic acid concentrations cause decreased muscle pH and increased fatigue. Research over the last decade has brought controversy around this mechanism, and no clear answer has yet emerged for exactly how fatigue occurs. The main takeaway for our purposes is that the anaerobic system provides a lot of energy for a short amount of time, before fatigue restricts energy output. This restriction is both voluntary, via that painful muscle-burning sensation that all rowers know intimately, and involuntary, via biochemical regulation processes.

An important thing to note is that energy systems are not binary, as in 100% aerobic or 100% anaerobic. Energy systems operate simultaneously, and the degree to which contributes to output depends on the duration-intensity trade-off. 

Aerobic and Anaerobic Rowing Performance

We might be tempted to think that the key to rowing faster for 2km is to just row harder. Let’s get the greatest intensity out of our energy system and go anaerobic as quickly as possible for as much of the race as possible. Anyone who has tried a “fly-and-die” 2km erg knows that it’s not this simple.

A highly trained anaerobic system can get you through 2-3 minutes of high intensity output. No one is ever going to be able to row 2km in under three minutes, so the duration of a 2km row means that it is always going to be majority aerobic. Also, remember that the downside of the anaerobic system is high fatigue. Hypothetically, if we could race 2km at anaerobic intensity, the accumulation of metabolites implicated in fatigue would become unbearably painful.

The goal of energy system performance in a 2km race is to get maximal aerobic power for the base of the race, sparing the anaerobic system as much as possible for the final phase of the race. At the sprint, we want maximal anaerobic power for the highest intensity and longest duration possible, “emptying the tank” at the end of the race. Basically, if our base pace for 2km is 400W (1:35 average split for a 6:22 total time), we should try to get as much of that 400W to be from more sustainable, less fatiguing aerobic power. This spares the anaerobic system for the final sprint, when we might tap up to 600W (1:23 average) and just try to hold it for that last 30-60 seconds of the race. This is why “fly-and-die” is a bad race strategy. The rower who sets out at too high of an intensity for their base pace taps into too much anaerobic system energy too early, and succumbs to pain and/or biochemical regulation processes before the race is over.

This may be why faster rowers racing 2km in shorter durations show higher proportional anaerobic values. They are getting more from their sprint, not more anaerobic contribution at their base pace.

Aerobic and Anaerobic Rowing Performance Correlations

It is an over-simplified approach to look at the energy system breakdown during racing and declare that because a race is dominantly aerobic, only aerobic training is important for success. In a sport won and lost by fractions of inches, it is critically important to get all of the energy you can out of the systems you have. Additionally, despite its relatively minimal contributions to 2km race energy compared to the aerobic system, anaerobic system performance is significantly correlated to 2km rowing performance.

To illustrate the importance of all energy systems in 2km rowing performance, I’ve highlighted takeaways below from research evaluating correlations between 2km erg performance and physical and physiological metrics, since 1995.

Russell, Le Rossignol, and Sparrow (1998) studied 19 elite rowers age 16-23, and found that body mass, VO2 max, and quadriceps strength as measured by isometric knee extension force correlated with 2km erg performance.

Cosgrove et al. (1999) studied 13 male club-level rowers, average age 20, with 2km erg times between 6.5 minutes and 7.75 minutes (on a C2 Model B). They found that VO2 max and lean body mass were correlated with 2km performance, and that VO2 max was the best predictor, explaining 72% of the variability.

Ingham et al. (2002) studied 41 elite male and female rowers, and found that power at VO2 max and maximal power and maximal force, as measured by a five-stroke max at 30 strokes-per-minute, were the strongest correlations to 2km erg performance. 98% of the variance in their 2km times was due to: power at VO2 max, VO2 at the blood lactate threshold, power at 4mmol blood lactate concentration, and maximal power.

Riechman and Zoeller (2002) studied 12 competitive female collegiate rowers (6 lightweight, 6 open) with an average 2km time of 7.7 minutes, and found that 75% of the variance in times was due to average power in a 30-second erg test (achieved in 15-20 strokes total). 12% of the variance was due to VO2 max.

Bourdin et al. (2004) studied 54 national and international-level male French rowers (23 lightweight, 31 open) with an average 2km erg time of 6.2 minutes. They found that peak power output in an incremental step test was the best predictor of 2km performance. They also found significant correlations in body mass, VO2 max, VO2 max at 4mmol blood lactate, and “rowing gross efficiency” (power output divided by oxygen consumption).

Huang, Nesser, and Edwards (2007) studied 10 male and 7 female club-level rowers with approximately two years of rowing experience and a 7.5-minute average 2km time. They found that vertical jump max height, inverted bodyweight row max reps, 1RM leg press, and athlete height were correlated with 2km performance. Height and leg press were the strongest predictors.

Akca (2014) studied 38 male collegiate rowers with an average 2km erg time of 6.6 minutes, and found that an equation of lean body mass, height, bench pull 1RM, arm length, leg length, weight, arm span, 30-second erg test at 10/10 damper setting, and leg press 1RM could explain 87% of the variance in 2km times. The researcher did not evaluate VO2 max in this study. The 30-second erg test was the strongest correlation of the performance metrics.

The general picture here is that aerobic, anaerobic, and strength performance are important and usually significantly correlated with 2km ergometer performance. It also helps to be taller and have greater lean body mass.

It is important to note that we’re only talking about 2km ergometer performance here. The degree to which 2km erg performance is predictive of on-water rowing success is still up for debate. Rowing strength coach Ed McNeely makes a data-driven case that they do not in the plainly titled, “Rowing Ergometer Physiological Tests Do Not Predict On-Water Performance,” (2012). McNeely studied 19 elite male rowers, and found that VO2 max, power at VO2 max, and peak power in a 45-second erg test at 200 drag factor were significantly correlated to 2km erg performance. However, none of these metrics nor 2km erg performance itself were correlated to 2km on-water performance in a single scull.

Milkulic et al. (2009) studied 638 rowers at the World Rowing Championships via race placings and self-reported 2km erg time. They found that 2km erg was generally positively associated with final ranking, but that significant correlations only existed for lightweight men’s single and double sculls, and men’s and women’s single sculls. They conclude with a suggestion for, “rowing coaches and rowing athletes to place their 2000-m ergometer performance times into a broader perspective.”

Ed McNeely suggests in his physiology chapter of “Rowing Faster” (2nd ed., 2011) that the variation due to anaerobic system performance is because rowers already do a lot of aerobic training, but may under-value, and therefore under-train, the anaerobic system performance. If we hold anaerobic performance equal, then aerobic performance is the greater determining factor. It’s more likely in our aerobic-dominant sport that we can hold aerobic performance equal, making anaerobic power the greater limiting factor for many rowers. 

This piece is focused on the 2km rower, but I’ll add that McNeely’s point holds particularly true for masters rowers racing 1km . Not only are the 1km races shorter, higher intensity, and more anaerobic (again, possibly up to 50-60%), but masters rowers often come from a background of 2km rowing or other, even more endurance-focused sports like cycling, and continue to over-emphasize aerobic work. Additionally, strength, muscle mass, and anaerobic fitness are more negatively affected by aging, beginning at age 30 and accelerating after age 60 (NSCA, 2019). There is a huge competitive edge to be gained for masters rowers who include more strength and shorter duration training along with their aerobic training.

Read More: Strength Training for Masters Rowers

So, what is YOUR limiting factor? We know from this research that trainable factors of both the aerobic and anaerobic energy systems are important for success in rowing, as is being strong in relevant muscle groups (legs, back, arms), and having as much lean body mass as you can while still maintaining fitness. There are lots of trainable directions here.

Takeaways for Rowing Training

Three major goals of rowing training come into clarity from this research review. 

First, build maximal aerobic power so that athletes can achieve base race pace primarily from the aerobic system, without tapping into anaerobically powered intensities until the final sprint. More advanced rowers may perform higher training volumes consisting of more U2/U1 work and more specific training, while less advanced rowers may perform lower training volumes consisting of more U1/AT work, and more cross-training. 

Second, develop strength and lean body mass to improve force generation, force transfer, and leverage on the oar. Aerobic fitness is the floor; general muscular strength is the ceiling.

Read More: Why Strength Matters in Rowing

Third, do enough specific (rowing/erging) short duration work above the anaerobic/lactate threshold so that rowers can build fatigue tolerance and perform technique effectively under high pressure conditions, for the final sprint phase.

There is a gap in the research for training practices of rowers of different levels. The majority of research on training practices is on elite rowers, and is primarily concerned with training intensity distribution. For example, there is rowing research available on the debate on “polarized training,” in which about 75% of training is low intensity and about 15% is above 90% VO2 max, versus “pyramidal distribution,” in which athletes perform a majority of training in low intensity zones and proportionately less in successively higher intensity zones. We know from this research (one, two, three, four) that multiple modes of intensity distribution can be successful, and that high-performing rowers are doing high volumes of training.

However, we also know from research on low back pain and rib stress injuries that high training volume, an accelerated path to high training volume and load, and total time spent on ergometers are all significantly correlated, even predictive, of development of injury. Injury researchers indicate that risk of low back pain and rib stress injury increases with competitive level of rower, due to the increase of training volume and overuse conditions. There appears to be a tradeoff of performance-enhancing specificity and increased risk of overuse injury from high volume specific training, particularly when that volume comes from prolonged erging (over 30 minutes continuous). Injury rates are often not reported in the training intensity distribution studies, and even if they were, to what extent is this applicable to sub-elite rowers and those not training 12-20 hours per week?

Read More: The Research on Low Back Pain and Rib Stress Injuries

Depending on the rowers’ age, experience level, competitive level, and other program factors, coaches and rowers may consider the following strategies for energy system development.

#1. To manage the specificity enhancement-injury tradeoff, consider more cross-training for aerobic endurance.

Using the training zones and corresponding workouts from the US-Rowing Level 2 Manual (pg. 127, 2014), we might do all U2 (low intensity utilization) and some U1 (medium intensity utilization) training via cross-training, then some U1 and most AT (anaerobic threshold) and above training via erging or rowing. Cardiovascular system adaptations are more general and systemic, including increased cardiac output, stroke volume, and blood flow to exercising muscles (Docherty & Sporer, 2000). Non-rowing modes of low intensity, long duration training such as cycling, swimming, running, hiking, and cross-country skiing can achieve the general cardiovascular system adaptations without the increased risk of overuse injury via prolonged erging. Rowers may then row or erg for higher intensity, shorter duration work to achieve more rowing-specific cardiovascular, neuromuscular, and muscular adaptations.

#2. Consider using heart rate pacing instead of 500-meter average pacing when doing erg training. 

Using 500-meter average pacing introduces error for athletes who over-perform or under-perform on the baseline ergometer test. The athlete may be training too hard, or too easily, and missing the benefit of training zones. There is error associated with heart rate zones as well, but I think we can get closer than we can with average split, especially for less experienced rowers whose erg test performance may be more erratic, and who can improve more rapidly from training.

#3. Periodize rowing training so that rowers have phases of increased and decreased ergometer use over a season and year. 

Periodization manages the specificity trade-off in the year-round picture, and provides opportunities for development of other athletic skills and abilities, while also reducing burnout from year-round erg training. A periodization picture comes together around our three major goals and the bigger picture of year-round training.

Off-Season/General Prep: Develop aerobic endurance via multiple modes. More U2 and U1 cross-training with selective, short duration specific erging or rowing for technical maintenance. Take advantage of the decreased erging/rowing emphasis to increase strength training for lean body mass and strength.

Off-Season/Specific Prep: Continue developing aerobic endurance via multiple modes, with slightly more emphasis on specific U1 training via rowing and erging, and continue developing strength and lean body mass. This prepares athletes gradually for future increases in specificity and training volume.

Pre-Season/Pre-Competitive: Maintain general aerobic endurance while increasing specificity and training intensity. Use strength training to maintain strength and muscle mass, while shifting to develop more peak power and maximal strength.

In-Season/Competitive: Highest specificity and intensity of erging and rowing training. Maximizing specific aerobic and anaerobic power, and preparation to race, while maintaining aerobic endurance, strength, power, and muscle mass.

This gets athletes 16-24 weeks of majority general aerobic cross-training and strength training emphasis, 8-12 weeks of gradually increasing specificity and intensity, then 8-12 weeks of high intensity, high specificity performance-focused training. Roughly half the year is spent building, not performing, with an 8-12-week gradual transition phase, and then an 8-12-week performance emphasis, followed by a 1-3-week rejuvenation phase.

---

Get Rowing Stronger!

“Rowing Stronger: Strength Training to Maximize Rowing Performance” is the comprehensive guide to strength training for rowing, from first practice of the off-season all the way to peak championship race performance, and for everyone from juniors to masters rowers. The second edition is available now in print and e-book.