The Rowing Machine: Useful Cross-Training or Just Another Hour?

Triathletes already have three sports to train. So when someone suggests adding the rowing machine, the obvious question is whether it's useful cross-training or just another hour that could have been spent swimming, cycling or running.

The rowing machine has a lot going for it. It is in almost every gym, it is low impact, it uses the legs, back and arms together, and it can produce a high heart rate in a short time. It is also one of the stations in Hyrox, covered in this batch's "Does Hyrox Make You a Better Triathlete?", and it features in many hybrid-fitness plans.

This article covers what cross-training research says about how much fitness transfers between activities, where the rowing machine fits for a triathlete, and how to avoid the back problems it can cause. The short answer: the erg can be a useful tool in specific situations, but the evidence suggests it shouldn't replace your swimming, cycling or running when you can do them.

What the rowing machine trains

In broad terms, rather than from a single study, the rowing stroke combines a leg drive, a hip hinge and an arm pull. That means:

• A large amount of muscle is working, which allows a high heart rate and oxygen uptake.
• The posterior chain, meaning the hamstrings, glutes and back muscles, is heavily involved.
• The upper body pulls, which neither cycling nor running trains much.
• There is no impact. Your feet stay on the footplates throughout.
• The movement is seated and repetitive, with a large amount of hip and spinal flexion at the start of each stroke.

The question for a triathlete isn't whether rowing is good exercise. It clearly is. The question is how much of the fitness it builds carries over to swimming, cycling and running.

Cross-training: how much transfers?

Sports scientists use the term "transfer" to describe how much fitness gained in one activity improves performance in another. Three pieces of evidence are particularly relevant.

The classic review

A 1994 review by Hirofumi Tanaka in Sports Medicine examined the evidence on cross-training between cycling, running and swimming. Its main conclusions:

• Some transfer of VO2max gains exists between activities.
• Transfer appeared greatest when running was the cross-training activity.
• Swimming training appeared to produce minimal transfer to VO2max measured in other activities.
• Cross-training effects never exceeded those produced by training the specific sport.
• Cross-training may be a useful supplement during injury rehabilitation, and during periods of overtraining or mental fatigue.

The review is over 30 years old and drew on mostly small studies, many in untrained people. But its central message, that cross-training helps but never as much as specific training, has held up.

Why fitness is sport-specific

A 2009 review by Millet, Vleck and Bentley in Sports Medicine compared the physiology of cycling and running, with a particular focus on triathletes. It concluded:

• VO2max is specific to the type of exercise. Most studies find runners reach a higher VO2max on a treadmill, while cyclists can reach a similar VO2max on a bike to the one they reach running.
• In triathletes, VO2max is generally similar on the bike and the treadmill, although the evidence was described as inconclusive and one study found a lower value on the bike.
• Muscles adapt specifically to a given task over time, sometimes without any change in VO2max.
• There is probably more transfer from running to cycling than the other way round.

Inference: if VO2max itself depends on the muscles and movement you test, fitness gained rowing is likely to show up most when you row, and only partly when you swim, ride or run.

Transfer in triathletes

A 2002 study by Millet and colleagues in the International Journal of Sports Medicine tracked 4 elite triathletes over 40 weeks, modelling how training in each sport related to performance.

• Cycling and running training transferred to each other.
• Swimming training didn't transfer to or from cycling or running.
• Running training had a major effect on overall triathlon performance.

This is a very small study using mathematical modelling, in elite athletes, so it shouldn't be over-interpreted. But it fits the pattern from the reviews: weight-bearing leg sports share fitness with each other, and swimming is highly specific. Inference: rowing, which uses the legs heavily but is seated and non-weight-bearing, probably sits somewhere in between, and its upper-body pull is unlikely to translate into faster swimming.

A non-running session that worked

A 1998 trial by Flynn and colleagues in Medicine and Science in Sports and Exercise tested what happens when runners add cross-training instead of more running. It involved 20 well-trained runners with an average VO2max of 4.6 litres per minute, matched for age and ability. The abstract doesn't give the sex split.

• Both groups kept their normal running and added three interval sessions a week for 6 weeks.
• The run-only group did these sessions running; the cross-training group did them on a cycle ergometer.
• The sessions included 5 × 5 minutes above 95% of VO2max, a 50- to 60-minute session at 70%, and short intervals above 105% and 115%.

The results:

• 5 km time-trial performance improved over time: from 1096.6 seconds before training to 1076.1 seconds at 3 weeks and 1068.6 seconds at 6 weeks.
• There was no difference between the groups. Running economy was similar too.

This trial used cycling, not rowing, and the cross-training was added to an unchanged running programme rather than replacing it. Inference: it suggests that for runners, a hard non-running aerobic session can do similar work to an extra running session over 6 weeks. That is encouraging for the erg, but it hasn't been tested directly.

Where the rowing machine fits

Putting this evidence together, the rowing machine is most likely to earn its place in a few specific situations. These are inference, not tested recommendations:

• When you can't run. If an injury stops you running but rowing is pain-free and your clinician agrees, the erg can help maintain aerobic fitness. This batch's "Can't Run? Aqua Jogging, the Elliptical and What Keeps Run Fitness When Injured" compares the options.
• When you can't get to the pool or the road. A short, hard erg session in a hotel gym or at lunchtime is better than nothing.
• In the off-season, when variety and enjoyment matter more than specificity.
• As a warm-up before a strength session.
• For general fitness, if you enjoy it and it keeps you training.

Where it steals from specific training

For most triathletes, time is the main constraint. TriForward's "Where Should Your Next Training Hour Go?" makes the case that the biggest race-day gains for many age-groupers come from targeting their weakest discipline.

Inference from the cross-training evidence:

• An hour on the erg won't improve your swim as much as an hour in the pool. Swimming appears highly specific.
• An hour on the erg won't improve your cycling as much as an hour on the bike. Cross-training effects never exceed specific training.
• It may replace some of the aerobic benefit of a run, but not the impact loading your bones, tendons and running muscles need to tolerate racing. TriForward's "Lifting for Bone" covers why swim-bike athletes need impact.
• A hard erg session adds fatigue. It uses your legs heavily, so it can compromise the next day's key bike or run session.

If your weekly hours are limited and you can swim, ride and run, those three are almost certainly the better use of your time.

The back pain problem

The rowing machine's main injury risk is to the lower back. A 2014 review by Wilson, Gissane and McGregor in the British Journal of Sports Medicine looked at low back pain in rowers.

• The lower back was the most commonly reported injury site.
• Among studies reporting 12-month data, low back pain affected 31.8% to 51% of rowers.
• A history of lumbar spine injury and the volume of ergometer training were the strongest risk factors in the limited studies available.
• Technique matters. Rotating at the pelvis at either end of the stroke was preferred over flexing and extending the lower back, which novice rowers often do.
• Technique can deteriorate as rowing gets harder and longer.

These were competitive rowers training far more than any triathlete would, and the data mostly came from retrospective questionnaires. Inference: a triathlete rowing occasionally is unlikely to face the same risk, but the lessons transfer. Start with short sessions, build volume gradually, learn the technique, and stop when your form deteriorates rather than grinding through.

Is rowing strength training?

Because the rowing stroke uses the legs, hips and back against resistance, it's sometimes described as strength and cardio in one. Inference: at the resistance most people use, each stroke is a relatively light effort repeated hundreds of times, so it is mainly aerobic training. The heavy strength work best supported for cycling and running economy, covered in this batch's "Gym or Home?" and "Heavy Lifting for Bike Power", uses heavy loads for few repetitions. Rowing doesn't replace that, and turning the damper up to make each stroke feel heavier mostly changes the feel of the stroke rather than turning it into heavy strength training.

That said, rowing does give triathletes something they rarely get elsewhere: repeated pulling with the upper back and arms, and a hip-hinge movement under load. For athletes who spend hours hunched on the bike, some of that may be welcome variety. Whether it changes posture, injury risk or performance hasn't been tested.

Women, masters and the evidence gap

The cross-training evidence summarised here comes mainly from small studies in runners, cyclists and elite triathletes, and the sex split is often not reported. The back pain data come from competitive rowers. Nobody has studied rowing as cross-training specifically in women triathletes or in masters athletes. Inference: masters athletes, who often benefit most from low-impact options when managing joint or tendon problems, may find the erg particularly useful during injury, but they should be equally careful about building rowing volume gradually, particularly with any history of back pain.

Practical application

1. Use the erg for a reason, such as injury, travel or winter variety, not as a default extra session.
2. Learn the technique first. Push with the legs, then swing from the hips, then pull with the arms, and reverse the order on the recovery. A coach or a gym instructor can check your form.
3. Start with short sessions, of perhaps 10 to 20 minutes, and build gradually if you plan to use it often.
4. Keep hard erg sessions away from key bike and run sessions, since they tire the same leg muscles.
5. Don't count it as swimming. If your swim is your weakest discipline, the pool is the answer.

A triathlon scenario

The following example is illustrative, not drawn from a study. A 51-year-old male triathlete has an Achilles problem, and his physiotherapist has advised no running for three weeks. Cycling is pain-free, and so is rowing. He normally runs three times a week.

Based on the evidence above, he might:

• Replace one run with a longer, steady ride, since cycling and running appear to share more fitness than other combinations.
• Replace another run with a short, hard erg or bike interval session, similar to those in the Flynn trial.
• Keep his swimming unchanged.
• Follow his physiotherapist's tendon-loading plan, since neither rowing nor cycling loads the Achilles the way running does. TriForward's "Calf and Achilles Capacity" covers this.
• Return to running gradually, rather than at his previous volume.

Common mistakes

• Treating erg time as interchangeable with swim, bike or run time.
• Rowing with the arms and back instead of driving with the legs.
• Doing long, hard sessions with poor technique, especially with a history of back pain.
• Adding hard erg sessions to an already full week, then wondering why key sessions suffer.
• Using rowing to avoid a running injury without getting the injury diagnosed.

What we don't know

• Whether rowing training improves triathlon, running or cycling performance. No trial has tested it.
• How rowing compares with cycling, the elliptical or aqua jogging for keeping run fitness during injury.
• Whether the upper-body pull of rowing helps open-water swimming in any way, for example in rough water. This hasn't been studied.
• How common back pain is in triathletes who row occasionally, as opposed to competitive rowers.

References

• Tanaka H. Effects of cross-training: transfer of training effects on VO2max between cycling, running and swimming. Sports Medicine, 1994;18(5):330–339. doi:10.2165/00007256-199418050-00005
• Millet GP, Vleck VE, Bentley DJ. Physiological differences between cycling and running: lessons from triathletes. Sports Medicine, 2009;39(3):179–206. doi:10.2165/00007256-200939030-00002
• Millet GP, Candau RB, Barbier B, Busso T, Rouillon JD, Chatard JC. Modelling the transfers of training effects on performance in elite triathletes. International Journal of Sports Medicine, 2002;23(1):55–63. doi:10.1055/s-2002-19276
• Flynn MG, Carroll KK, Hall HL, Bushman BA, Brolinson PG, Weideman CA. Cross training: indices of training stress and performance. Medicine and Science in Sports and Exercise, 1998;30(2):294–300. doi:10.1097/00005768-199802000-00019
• Wilson F, Gissane C, McGregor A. Ergometer training volume and previous injury predict back pain in rowing; strategies for injury prevention and rehabilitation. British Journal of Sports Medicine, 2014;48(21):1534–1537. doi:10.1136/bjsports-2014-093968