Making the Boat Go Faster
I attribute a substantial part of my learning curve in elite sport to working with the South African national rowing squad between 2013 and 2016. Coming in to a programme that included World and Olympic Champions, when my only previous exposure to rowing had been watching it on TV every four years, was an eye-opener. This was a true “high-performance” sports system if ever there was one (and I say that because the term is massively overused). The programme that achieved a gold medal at the 2012 Olympics and placed five boats in the top five in 2016 was (and still is) expertly led by Roger Barrow. My time spent on the water with him and the other coaches - listening to their cues, watching the athletes move and dissecting video footage after sessions - not only taught me about the sport of rowing but has also influenced how I approach the biomechanics-coaching relationship.
The performance measure in rowing is simple – the crew with the highest average velocity over the 2000 m race wins. Producing and maintaining that velocity over the ~6-7 minute race, however, is a complex interaction of physiology, fluid dynamics, equipment rigging, technique and strategy. A number of excellent books and articles are available that unpack many of these components in great detail (see reference list at the end of this post, for example). In this post, I will highlight just one of the key technical features that was emphasised by the coaches I’ve worked with.
To start with, let’s summarise one of the main biomechanical principles at play - when a force large enough to overcome an object’s inertia (mass) is applied, it causes a change in the object’s motion (acceleration), as described in Newton’s second law. In rowing, propulsive forces that move the system (rower + boat + oar) towards the finish line are applied to the water by the blade of the oar. The rower produces and applies forces across various phases of the stroke cycle that contribute to the propulsive force that moves the system. As the blade enters the water, the rower initiates force production by contracting the leg muscles and pushing against the foot stretcher. The muscles of the trunk and upper body work to apply a force at the oar handle, creating a mechanical link between the foot stretcher and oar handle that relies on the rower’s strength across multiple muscle groups to generate and transmit force. The oar acts as a lever, and the force applied by the rower to the handle is therefore directly related to force at the gate and the blade.
Breaking it Down
The rowing stroke is typically divided into two phases – the drive and the recovery. Various definitions have been used for the precise transition between the two but, essentially, the drive phase starts at the catch as the blade enters the water, the oar handle begins to move towards the rower, and the legs extend. The recovery phase happens after the finish (blade removed from the water) as the rower slides back towards the catch position. With so many moving parts in the system, though, this simple two-phase breakdown doesn’t give us enough detail to really understand rowing technique.
Based on the acceleration patterns of the boat and rower, Kleshnev described a subdivision of six periods within the drive phase (D1-6) and three periods in the recovery phase (R1-3).
At the end of the recovery phase, the boat is slowing down and the athlete prepares to change their direction on the slide by increasing the force on the foot stretcher in R3 and D1, and then increases their acceleration in D2 as the blade enters the water. In D3, the emphasis is on the force at the handle, which transfers force to the boat at the gate and causes initial boat acceleration. This is then followed by the strong leg drive as the rower accelerates (D4). In D5-6, the emphasis is on the handle force and the movement of the trunk and arms dominate because the legs are almost fully extended.
The coach’s call of “connection!” featured in a lot of my video footage when filming rowers on the water. Although we didn’t have the tools to simultaneously capture video and measure boat acceleration, the connection that the coach’s eye was looking for seemed to me to be aligned with the “D3” phase, which happens after the blade is fully immersed and the athlete has started to initiate the drive with their legs. The execution of each of these subphases has a knock-on effect to the next one. The rower has to execute the “turn”, and simultaneously place the blade in the water in D1-2, so that the connection of the hands to the water can be effected in D3 to “move the boat”. If that doesn’t happen, the leg drive through D4 will be less effective. The D1-3 subphases are completed in about three tenths of a second (depending on boat size and stroke rate). This series of actions therefore demands precision timing.
The image sequence below gives some idea of the fine positional changes that occur at each of these subphases in the drive. These weren’t captured at the same time as any objective data, so they may not be perfectly matched to the acceleration curves, but it was our next-best approach to interpreting typical force, acceleration and velocity data that has been published in relation to what we were looking at in the rowing motion.
So, when you watch the rowing events at the Tokyo Olympic Games, see if you can spot the “connection” in every stroke, and remember that these athletes are not just human powerhouses, but expert technicians too.
I’ll be cheering loudly for the two South African boats – the men’s pair the men’s four. Watch the squad’s Stories of Courage and hear behind-the-scenes accounts directly from the athletes on The Row Show, and you will be too!
- Baudouin A, Hawkins D. A biomechanical review of factors affecting rowing performance. British Journal of Sports Medicine. 2002;36(6):396-402. doi:10.1136/bjsm.36.6.396
- Kleshnev V. Biomechanics of Rowing: A Unique Insight Into the Technical and Tactical Aspects of Elite Rowing. Second edition. The Crowwood Press Ltd; 2020.
- Nolte V. Rowing Faster. Second edition. Human Kinetics, Inc; 2011.
- Soper C, Hume P. Towards an ideal rowing technique for performance: The contributions from biomechanics. Sports Medicine. 2004; 34 (12): 825-848. doi: 10.2165/00007256-200434120-00003.