PART 1 of 2
Written by Martin Kay
Whenever we want to run a nice hot bath, the first thing we do is put the stopper firmly in the plug-hole. No point in turning the tap on full blast if the water is trickling away unseen.
Applying full power in the boat in the race is everyone’s aim. What might we be doing to slow the boat and dissipate our hard-earned power gained in training? Consider each item, and a suggested approach to improving efficiency is shown in italics.
AT THE BLADE
Everything we do to improve the stroke effectiveness requires concentration, particularly when introducing a new focus, because the default position is to revert to our old habit. This will continue until we get the habit change, which is signalled when we start getting the alert that a previous substandard stroke was an exception. Sometimes this habit change may take months of repetitions to get implemented, so do not be surprised if it takes a while! The aim is…Perfect Every Time.
Any hint of dirty water around the spoon at the finish tells us that the pressure has come off at the final part of the draw, allowing the water to catch up behind the spoon, which backs the boat down momentarily, after the boat has accelerated away in response to your power applied.
Modify the hand speed, the shape of the release movement and the final pressure until this effect disappears. Perhaps consider how the javelin thrower moves, with the final whip coming through the forearm, wrist and fingers to send the javelin faster on its way.
Every coach will have their own arsenal of exercises to address these points.
One signal of inefficiency is a knock or clunk at the turn, telling you that the sleeve is coming away from the pin just at the extraction, i.e. that the pressure at the pin has come off too early, indicating weak draw at the finish. Aim for “silent running”.
The depth of the spoon in the water during the drive is key to getting efficiency and the right “feel” of each stroke. Too deep and its hard work. Too shallow or bouncing out and you tear the puddle, losing rhythm and balance.
Set up your fore and aft pitch correctly at every position, also decide what lateral is needed and check it is the same both sides. C- Cups can move, so this is an essential item of regular maintenance.
Is the spoon clean and correctly painted? Too shiny and it may not grip the water well, so an eggshell finish, similar to manufacturers’ standard, may benefit you. Try this out to compare the feel of alternative paint finishes.
Every time your blade touches the water on the way forward will slow the boat a little. In a 2000M race this insidious effect is multiplied by 250.
Does the handle touch your knees as they rise? When are you feathering? Are you rolling the boat?
Do you love a tailwind? Many people do, but why…do they think it should feel easier? Because the boat might be moving 15%, even perhaps 20% faster than in a strong headwind, all these bladework perfections become more difficult to carry out properly, if you are actually going to achieve going “faster enough”.
Think “quickness” at the turns in the tailwind. For example a 6:40 time over 2000M means a boat speed of 5m/sec. The boat therefore travels 5cm (2 inches) in every 1/100 sec that passes.
DRAG FORCES
At a constant average boat speed the rower’s power input is equal and opposite to the sum of the frictional effects of all the various drags imposed by surrounding conditions and within the boat.
1. Hydrodynamic Drag
This is the obvious factor which we cannot avoid and all know; it takes several forms so we try to reduce them:
Skin Friction varies down the hull, as the boundary layer of water changes. All imperfections on the surface contribute, therefore any blips, bumps, tape or rough areas and unfinished repairs need to be treated. Drying off marks have a significant effect too.
It is essential to clean down after every outing and leave no droplets on the racked boat because dissolved minerals in water will be left as rough marks on the skin when they dry. (This is not easily seen on a white boat unless you look along it into the light). Also ingrained dirt and gelcoat stains need to be removed using a recommended cleaning agent.
Wave-making is a major destroyer of speed, and it is one area which you can improve by your own technique. There are four causes:
a. Boat rolling – the most accessible one you can cure to avoid surface ripples.
Straightforward good blade work at the finish and relaxation coming forward to set up the boat.
b. Pitching: If the stern dips at the catch, it causes lateral waves which might not be visible. This dipping also adds to skin friction.
Examine your personal adjustments to improve the boat trim fore and aft. Then address how you approach the entry and catch. (plenty of exercises exist for this)
c. Wash: This visible wave leaves the boat at an acute angle from near the bow section, and it shows as a ‘V’ running astern. Wash is unavoidable, as with all craft, however the severity of this can be reduced by correct movement, particularly at the finish, sympathetic to the boat. It is a complex factor, so there will be no easy short cut to getting an improvement.
To demonstrate the wave making arising, just rock the boat fore and aft when stationary and see the result. Then jerk your shoulders up and down about 20 times to get the hull to make lateral waves and see how much energy this also consumes for no gain.
Watch the wash as you paddle, and experiment with all parts of the draw to see what improvements you can get. Monitoring and getting running comment from the bank or the launch is most helpful.
d. Yawing (sideways-wiggle): this can occur notably in sweep rowing when the pressure and timings are not matched between the sides. Particularly in the pair, finding the optimum complementary pressures which give the best boat response is a whole subject in its own right. In sculling there may be differences in hand pressures, shapes and speeds at the turns.
Watch the wake just at the stern of the boat – is there a “wiggle” wave occurring at the finish? Then alter the individual power and speed patterns until it disappears.
2. Aerodynamic Drag
We all know the feel of air resistance in a headwind, and we train to accommodate it. Contributory actions we can take to reduce this resistance are:
Oars and sculls: Use a lower profile shaft with better aerodynamics
Rigger: Not much can be done here. Just keep it clean and polished.
Crew profile: Some research suggests that in the double and pair, the taller-sitting person should be at bow if crew selection permits. This shelters the stroke from airflow to some extent.
Crew hair: Long and flapping hair in an airflow has a significant drag effect.
Tie it in a top knot or bun, cut it short and/or wear a cap.
Clothing: No airflow effects are discernible on account of material choice.
Avoid any fluttering of kit.
PART 2 to follow..
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