erg/boat time

Question
Hi,if 2K ergo times are 7.58,7.59,8.20 and 8.30 what time should the boat pull in a coxed jnr quad  15 year old girls?Is there a formula one could apply?I am assuming good weather and perfect water.
Many thanks
Rory

Answer
Hi Rory: It's a very interesting question.  When I read your question for the first time, my gut answer was going to be that there is no way you can correlate erg times with boat scores.  I thought this because you can't determine if someone rowing a good erg score is rowing technically sound -- in other words, would their hands and slide technique result in a boat on the water checking or having bad set.  

I ran a Google search on the topic, I did find some studies on the topic.  Unfortunately, most of them involve some pretty heady math.  But I did find one article that might be worth reading.  Check out the link below.

http://www.concept2.com/us/support/manuals/pdf/Newsletters/NewsForCoaches_Mar08....

I think the general consensus among the scientists is power generated on the ergometer has a positive correlation to boat speed.  It also states that a heavier person will generally have a lower erg time than a lighter competitor (assuming both are equally conditioned).  But it also is assumed that the heavier you are the more you will cause the boat to sit deeper in the water, which increases drag, which slows the boat down.  I'd guess your girls quad wouldn't have that much drag (although the coxswain would).

Looking at the erg times of your quad, they are all above average for 15-year-old girls, with a couple of your girls pulling times in the Top-10%.  If they have good set and swing together, I think they can row a good time.