Sign Up
Sign Up
Did you know that… biomechanics in coastal boats was found to be very similar to flat-water rowing, with a few quantitative differences due to the heavier mass of the coastal boat? In August, BioRow performed biomechanical measurements in coastal rowing for the first time. Four mixed doubles were tested multiple times in various combinations. The test protocol consisted of 5 min. of continuous rowing with increasing stroke rates every minute: 22–26–32–36–40 spm.
Boat acceleration and velocity curves showed similar patterns with flat-water rowing, as did force curves and other variables. In coastal rowing, peaks of boat acceleration were shallower and of lower magnitude because the boat was significantly heavier (52 kg) compared to the flat-water double (32 kg). Therefore, the boat velocity curve was smoother in the coastal boat, with fewer fluctuations. However, the heavier mass and wider shape of the coastal boat increased its gross drag factor by 14.0%, which would decrease speed by 4.3% compared to the flat-water boat at the same rowing power, technical efficiency, and weather conditions.
It would be interesting to compare data from the same rower in both flat-water and coastal rowing. At similar stroke rates 32–33 spm, force curves were nearly identical, with only slightly higher force at the finish in the coastal boat, which could be explained by lower handle velocity in the double.
The data obtained from mixed crews allows us to give an objective answer to a very popular question in the rowing community: “When athletes with very different sizes, erg scores, and power production row in the same crew, how should they be rigged to compensate for the differences?”
A general principle of efficiency in crew boats is synchronous timing. Equal oar angles are not a true biomechanical requirement; they may be used only “to look better in photos or videos.” Many successful crews use different oar angles.
Synchronisation of seat movements at the catch is the most important factor, because it directly affects stretcher forces, inertial efficiency, etc. Catch synchronicity does not depend on rigging, physiology, etc., because it is defined by rowers’ movements during recovery, which are completely unrestricted. Instead, it depends purely on the rowers’ shared sense of rhythm, balance, and relaxation, which is developed with experience of rowing in a crew.
Timing at the finish is also important, though to a lesser extent, because it affects boat balance, recovery rhythm, and indirectly the timing at the catch. To achieve synchronicity at the finish, rowers must have very similar drive times. It is commonly believed that this depends on rowers’ force and power production, and therefore on their size and physiology. This would be true if each rower were using their own ergometer flywheel (mobile ergs might be connected on slides in a “boat”), where angular velocity would differ in proportion to individual power output, leading to different drive times. However, on the water, all rowers share the same “flywheel” – their boat, which velocity is the same for all rowers and depends on the sum of power from the entire crew.
There is, however, another factor affecting handle velocity — blade slippage in the water — which does depend on force and power production. But its contribution to handle velocity is small for two reasons:
This theory was confirmed with measured data. A male rower in one of the mixed doubles produced 42% higher average force, 48% higher rowing power, and rowed 5.4% longer stroke with similar blade depth. As a result of higher force and power production, the male rower’s average handle velocity was 1.7% higher. However, the longer stroke length overcame the rigging effect, so the male’s drive time was 3.6% longer, and his finish was 31 ms later than of the stroke-female rower. This suggests that using similar or even lighter oar gearing for the male rower could improve synchronization and crew dynamics.
Conclusion: Rowers with very different physiology and force/power production can be synchronised and row successfully together in a crew with similar or even identical rigging. Other factors, such as stroke length and depth of blade work in the water, significantly affect drive time and must also be considered when selecting oar gearing.
This is a short version of the Newsletter. To access the full text, please subscribe to BioRow membership here: https://biorow.com/membership/
©2025 Dr. Valery Kleshnev