We adopted with the approach employed by Valery Kleshnev of BioRow, which is to use a set threshold. Clearly, that set threshold may not truly define "slip" and "wash" as we think of it for a smaller, lighter, or less powerful athlete. This threshold is also pretty much irrelevant if you’re paddling as much of the stroke will be below this value. However, if you think of these measurements more as a relative target than as an absolute target, the fixed threshold is simple and effective. For example: "I tend to lay back too far and lose my grip on the water. When I do that, my wash value is 18. When I keep my core engaged and shorten my finish slightly, my wash drops to 10 or 11 and my speed increases. I'm going to try to keep my wash value below 12 at steady state."
This discussion, in general, points out our philosophy with this product. We may not be starting with 100% perfect measurements, perfectly executed. There has simply not been broad enough access to rowing biomechanics data like this to determine the absolute best way to measure everything on day one. We teamed with Dr. Kleshnev and BioRow to ensure we had a strong, validated starting point with measurements that have helped him coach many athletes to world-record times. But, we are also sure we and our customers are going to learn new approaches from expanded use of this system, which is why we are anxious to get it on all sorts of boats with all sorts of athletes. We have been using it in our own rowing and coaching, and we have seen first-hand that these measurements make sense and work in practice. And, both the Oarlock and the SpeedCoach can be updated in the field as we continue to make improvements in the future. Alternatives here would be to make these a user-settable threshold value, or to define them as a percent of peak force. We may test these approaches in the future.