Getting the right angle on things
Recently the discussion page at Rowperfect.uk hosted a discussion about oar angles, length and levers and fulcrums. The host gave some practical advice to a knowledge seeking coach, but in doing so was somewhat illogical, or, at least, inaccurate, about some basic physics. Peter O’Connor a well-known NZL coach, renowned for strong opinions about rigging, corrected some of Rebecca’s physics and added some opinions. I am now going to add more opinions and confuse the debate some more.
When we grew up it was accepted that an angle of more than 450 at the catch meant you were pinching the boat and was thus a bad thing. Purely empirically this has got to be doubted now, many (most?) good crews reach past 450 and they all go faster than we did in our youth. I suggest that although going past 450 may reduce the efficiency it doesn’t slow the boat down. As a general rule I work from the assumption that length is good, that the longer the blade is in the water the faster is the potential top speed of the boat.
Now, as always in rowing, there is a but; or, indeed, several buts. How is the length achieved? If the athlete packs up very tight Rowing, single sculler Conal Groom at the catch, Lake Washington, Seattle, Washington State, Pacific Northwest, released. COPYRIGHT:Joel Rogersat the catch the initial leg drive is inefficient. If excessive lay back is used there is much force downwards on the bow at the finish. If the rigging is changed to give a longer stroke then the gearing may be outside the efficient range for the athlete or crew. This is standard rigging – there is no such thing as a free lunch. Change a setting to improve one parameter and several others get changed in other directions. Given these constraints it is easy om see that there is no general optimal angle to reach to. The best angle depends on athlete size, shape, and strength, boat size and a host of interlinked rigging options.
Most coach education course and self-help books give suggested angles for oars or sculls to traverse during the stroke. An example can be found here, but the consensus is around 900 for sweep and 1100 for sculling. The other age old consensus is that faster boats should have more of the swept angle in front of the pin than is the case for a slower boat. Thus an eight may be rigged so the oars reach 550 past the pin to the catch and only swing 350 past perpendicular to the finish. In comparison a pair might be set to 500 and 400.
So how does this help our searcher after knowledge? Generally a good rule of thumb is to rig as all the others do. Rigging has evolved to standards because they work. Unless you have extreme athletes, extreme in size, power or speed, what is good enough for the bulk of us won’t slow your crew down and you can focus on what really makes a boat fast, good training and good technique.
Training is outside of the scope of this little piece but there is one hugely important, and often neglected, piece of technique that repays attention from us all. I call it effective length. The length of the arc the oar swings where it is connected to the water. Not the length measured by most eyes which is the total arc swung but the arc where the oar, and thus the athlete, is doing something useful about propelling the boat.
So to answer Glenn, the original questioner, I would say, “set your athletes so they reach a bit past 45degrees at the catch and spend time helping them to learn how to place the blade accurately at this point and not to miss water”.At the other end of the stroke stay in the water till the body gets in the way. At this level more time in the water gives more speed.
This Post Has 4 Comments
hi Rebecca
I would also like to add a comment to catch angles,
As mentioned there are ideal catch angles for all boat types,
I believe that the athletes should aim for a slightly longer angle than the ideal as there is a element of slip before the power is applied effectively to the oar/handle, one would need to be extremely fast at the catch to eliminate that slip at the so called effective angles.
My advice is to add at least one degree more and this will give the time needed.
Hope this is of value to you!
John
Greetings.
The greater the above water catch angle, the less reversed speed the blade needs to enter the moving water.
Here’s how to achieve this speed reversal very quickly. Leave the elbows bent about 10′ in the recovery. As your torso slows against your knees the momentum of the blade pulls your arm straight. As this happens square the blade, and then drop it into the water as the arms rebound to the 10′ bend. Your torso accelerates off your knees, assisted by some plyometric muscle use, and pull on the blade builds.
A useful advantage of a LONG reach IN THE WATER is that the blade moves FORWARD due to boat speed. I find that my blade finishes the stroke AHEAD of its entry point despite the inevitable slip while being pulled.
I use a 1:1 work/recovery ratio, at about 26spm.
Regards.
Graham, I cannot keep my arms bent in the recovery – just not strong enough to hold that posture while driving with the legs. So not sure this helps.
Don’t keep them bent. Just relax them to be straight or a little bent as they like. The main thing is not to use energy on something unnecessary, such as straightening your arms.
Necessary arm work is:
a. Holding the handle down during the recovery.
b. Feathering and squaring.
c. Bending the arms to finish the work.
d. Pushing the handle away at the release.
I mentioned above the benefit of the blade moving forward in a long reach. It also loses air drawn in as it enters. The longer reach will allow a quicker, cleaner entry because of reduced relative water speed. Increasing the catch angle from 30′ to 45′ could increase the travel of the spoon about 800mm in a scull, given a similar release angle.
The experts use a long reach!
Regards