Lawton et al. (2013) refer to a phenomenon that over the past 30 years, volumes of endurance training have increased by more than 20% among elite rowers. This raises a problem that rowers might have relatively less time or energy for performing strength training.
The authors hypothesize that instead of strength training, intensive resisted on-water training (towing ropes or paired crew rowing) could be used to maintain or increase lower body strength.
To test their hypothesis, they conducted a study with 10 elite female rowers. The subjects covered two 14-week on-water training cycles, either rowing alone or together with strength training. The first cycle included two resisted rowing (‘towing ropes’ e.g. 8 x 3 min), six endurance rowing (e.g. 16 – 28 km at 70-80% maximum heart rate) and two rate-regulated rowing sessions (e.g. 8000 m at 24 spm) each week. After four weeks, similar cycle was repeated with addition of two strength training sessions (e.g. 3-4 sets x 6-15 reps) per week.
It was found that intensive on-water rowing that included resisted rowing sessions, in general maintained but did not increase lower body strength. However, when strength training was added, lower body strength (leg press) was significantly increased (9.1% ± 8.5%, p = 0.01) while no changes in body mass was observed.
What to learn from this?
High intensity non-fatiguing strength training might be used in training plans of elite female rowers to increase their lower body strength, without any change in body mass. Nevertheless, you should be cautious in interpreting the results to male rowers as their adaptation might be different.
Source
Lawton TW, Cronin JB, McGuigan MR. Does on-water resisted-rowing increase or maintain lower-body strength? Journal of Strength and Conditioning. DOI: 10.1519/JSC.0b013e3182736acb