the ergonomics of rowing

8/6/2019 The Ergonomics of Rowing

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THE ERGONOMICS OF ROWING BY JIM FLOOD

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The Ergonomics of Rowing

Getting to grips with how

to set up your boat

Jim Flood


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The Basic Ergonomics of Rowing

If you have started rowing and are beginning to feel a bit addicted to itand you want

to know more about what you need to know to improve, this article may help you. The

aim is to empower you to take action that will make rowing easier by making some

adjustments to ensure that the boat fits you more comfortably so you will find it easier to

achieve a good rowing technique.

Unless you have bought your own boat, you will be using club boats that are often

bought on the basis of 'one size fits all'. For example in my club, the size of the shoes

fitted in most of the boats is size 11 (45). So if you are about 1.9 m tall (6' 3) and

weigh around 90 kg (just over 13st) you will not need to make many adjustments. If you

are much smaller (or larger) then, in terms of how the boats and blades are set up, you

are facing additional difficulties in learning to row welland I could argue that you are

being discriminated against!

I've used the term ergonomics in the title of this article because this is defined as the

science of the design of equipment, especially so as to reduce operator fatigue,

discomfort and injury. So this is not just about comfort, it's also about avoiding injury

due to undue strain.

A word of warning! You should not make any adjustments to boats or blades without

permission. Check with your club about the protocol for making changes or for selecting

equipment that is a better fit for you. The aim of this article is:

To provide information that should enable you to have an informed discussion with

a coach about the changes that can be made and the benefits that could result.

To enable you to take measurements that will indicate if the boat and blades are

likely to be a good fit for you.


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1. Choosing a boat

Your choice of boat could be limited by what is available but somewhere in the

boathouse there should be a list of boats that give the weight category. A single scull

described as a '70 kg' boat is designed for a rower of 70 kg. This will be okay for

rowers between 65 and 75 kg, but if you are heavier the boat will be lower in the water,

and if lighter the boat will be higher in the water. Confusingly you might see '4s' and

'8s' listed as 70 kgwhich is the average weight of each crew that they are designed

for.

If you or the average weight of your crew is 10 kgs more than the boat is designed for,

the riggers will be closer to the water. The effects of this are:

limited vertical movement of the blade making it difficult to finish the stroke with

the blade handle touching the chest

difficulty in tapping down to extract the blade from the water at the end of the

stroke

on the plus side that the boat will be more stable in the water and easier to

balance

If you or the average weight of your crew are around 10 kgs less than the boat is

designed for, the effects are:

the handles of the blades will feel too high for comfort

the boat will feel unstable and difficult to balance

If there is no other boat available, it is possible to make adjustments to the height of the

swivels so that the height of blade handles is more comfortable see the section on

Swivel Height.

Crew/individual too light for the boat


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Crew/individual too heavy for the boat

These drawings exaggerate the effect but the general idea should be obvious.

2. Choosing Blades

With luck, the blades in your boathouse will be marked either by size or in terms of the

athletes who should use them: e.g. 'Senior Women', 'Junior Men'. Generally the taller and

stronger you are, the longer the blade you will use. However it is worth checking the

length of the blades that you or your crew are using different length blades in the

same crew can cause problems with the balance.

If you are rowing 'sweep' that is with only one blade, then the length of blades for the

smallest and lightest rowers will begin at around 370 cm. For tall strong rowers the

length will be up to 380cm.

This is only part of the story. Moving the collar changes both the inboard and outboard

which is like changing the gearing on a bike. Make the outboard smaller and it is easier

to row but you have to take more strokes to cover the same distanceand vice versa.

OutboardInboard

Length

SpoonCollar Sleeve


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Summary ball park table for club level rowers (sizes in centimetres)

Sweep oar rowing (cleavers) Blade length Outboard

Small light rowers 370 258 - 256

Strong heavy rowers 375 258 - 256

Sculling blades (cleavers) Blade length Outboard

Small light rowers 284 200 - 198

Strong heavy rowers 290 202 - 200

You would expect to have lower gearing (shorter outboard) in a slow boat such as asingle or a pair, and higher gearing in faster boats such as a quad or an eight.

Blue clam washers allow a quick change of outboard

The problem with using clams in this way is that they also change the inboard which

can affect the body position. See Section 4 for the measurement of the overlap.

The table of oar measurements provide broad guidelines so don't worry if the blades you

are using are well outside the recommended range. For example, when coaching

beginners I often give them long high geared blades for two reasons: it slows the stroke

down and it makes the boat easier to balance.

Remember that these measurements provide a basis for discussion with your coach

who might have good reasons for setting up your blades they way they are, or because

of a disagreement with the figures provided. It is a case of different sources, different

numbers!

Collar black circling part

Sleeve white ridged part


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3. Sitting comfortably

Okay, you have chosen your boat and blades (or had them chosen for you) and you

have the boat on the water ready to go.

Sit in the boat with your legs straight (knees locked down), your feet in the shoes and

holding the blade at backstops position (leaning back slightly). With the blade (or blades

if you are sculling) feathered on the water (or better still, square and floating in the water)

and the boat level, you can check the both the position of the footstretcher, the heel

cups and the height of the blade handle.

Footstretcher position for sweep oar rowing

When in the right position, the end of the blade handle should not protrude beyond your

rib cage. If it does, move the footstretcher towards you. If the end of the handle can

swing in so that it is in front of you, move the footstretcher away from you.

Footstretcher position for sculling

At the finish position, with thumbs over the ends of the handles, the gap between your

hands should measure the same as the width across your knuckles. Slightly more, up to

one and a half times the distance across your knuckles, is preferable to less. If the gap

is smaller, move the footstretcher towards you, if too large move it away from you.


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Height of the heel cups

Sitting at backstops with blades flat on the water, check that you can swing your body

forward into the catch position. The aim is to do this with the spine straight and pivoting

from the tops of your thighs so that your pelvis stays in line with your spine (a neutral

back position).

If this is difficult try moving the heel cups lower. The penalty might be that you find the

backs of your legs scraping on the end of the slide. If you find that you can swing over

to the catch position easily and with good posture, try raising the heel cups to achieve a

stronger drive.

In general you will improve your leg drive if you row with the heel cups as high as good

posture at the catch will allow.

Holes that allow the heel cups to be raised or lowered

If you have small feet and the boat is fitted with size 11 shoes (standard in my club)

then you have an obvious problem. Wearing a thin pair of shoes or slippers inside the

shoes fitted to the footstretcher is one solution.

Height of the handles for both sweep and sculling

The height of the blade handle should be level with a point about 5 centimetres above

your sternum. This is at the centre of your chest where you can feel the end of your

rib cage.

Generally it will feel easier to row if the blade handle is slightly higher than this position,

however it will reduce the force that can be applied in the water so you go slower.


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4. Checking measurements

The diagram below gives a range of measurements you could expect to find on your

boat. Where a range is given, the larger number relates to larger rowers and vice

versa. Note that in sculling, assuming that your hands cross left over right, the bow side

swivel will be about 0.5 cm higher than stroke side.

If you have not got a height stick (ask to be shown one), you can check the height of

the swivel above the seat with a spirit level, a straight piece of wood and a tape

measure. Ensure that the boat is set up to be horizontal on both axes and the swivel is

parallel to the boatwhich it isn't in the photograph! Place the wood in the lower part of

the swivel and the tape measure on the lower part of the seat. Take the measurement

when the spirit level is horizontal.

If clam washers (red in the phot0) are fitted the height of the swivel above the seat can

be changed quickly. To raise the swivel, slide the clam out, lift the swivel up and insert

the clam underneath. Alternatively, remove the top nut, count and remove the washers,

remove the swivel and adjust the height by changing the position of the appropriate

number of washers.

Span sculling 158 160 cm

Spread sweep 80 90 cm

Height of seat above heelcups 15 18 cm

Height of bottom of the swivelabove the seat

Height of the swivel above thewater 22 cm sculling, 24 cm


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It might occur to you that the overlap of the sculling and sweep blades will be affected

by changes in the outboard/inboard of the blade, and by any changes in the span or

spread. For this reason, the inboard can be adjusted on modern blades. It should be

obvious that these checks are made when the blades are at right angles to the boat.

In my experience the measurements that are most neglected are the overlap of the

blades and the height of the swivel above the water (which changes with the weight of

the crew). A large difference from the guideline figures given can be a cause of

discomfort and poor posture.

5. Effect of changes in the span or spread

Be clear about which is which. Span is the distance between the swivel pins in a

sculling boat. Spread is the distance from the swivel pin to the centre line of a sweep

oar boat.

To check the symmetry of sculling riggers it is necessary to measure the spread.

What will you feel if span or spread is increased from a position that feels familiar to

you? At the catch, you will be unable to reach as far forward.

Sculls overlap 18 -22 cm

The end of a sweep bladeoverlaps the centre line by 30cm


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The drawings above show a top view of rowers, one in a sculling boat, the other in a

sweep boat. The position of the rower in each case shows the limit of their reach at the

catch with good posture. Two positions of the swivel pins are shown and the effect

they have on the angle of the blade. It is possible to reach further by collapsing the

body forward but this causes a loss of leg drive.

In each case an increase in the span or spread causes an increase in the angle relative

to the centre line of the boat and a loss in the length of the stroke (it is the same

effect at the finish position).

A common fault that coaches criticise is 'rowing short'; that is, not getting the spoon of

the blade far enough behind your body at the catch and tapping out of the water too

early at the finish. In my experience a common cause of this problem is too large a

span or spread for the rower to cope.


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6. Stern Pitch of the blade

Stern pitch is the measure by which the spoon of a blade is inclined from the vertical

when the blade is in the square (vertical) position. This is measured in degrees with 0

degrees being absolutely vertical. A plus sign indicates a forward inclination of the blade

although the + sign is often omitted because all blades should have a positive pitch of

between 4 and 6 degrees.

Positive pitch makes the blade easier to row with as the forces on the blade tend to

push it upwards and to keep it near the surface of the water. Rowing with zero or

negative pitch is difficult as the blade is more difficult to control. Beginners will find it

easier to row with more pitch but this results in a loss of force so experienced rowers

want less pitch. Many clubs set the pitch at 4 degrees which is fine for experienced

rowers but not so easy for beginners.

A blade entering the water withnegative pitch is forced downwards


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If you have not got access to a pitch gauge, ask to see one and to be shown how to

use it. You can also check the pitch at the end of the blade using a spirit level and tape

measure. Set the boat up so that it is horizontal in both axes. Clamp or hold the blade

against the pin side of the swivel and at right angles to the centre line of the boat. With

the spirit level vertical and touching the top edge of the blade, measure the gap at the

bottom edge. An alternative method is to use a plumb line hung from the top edge of

the blade.

If you measure the width of the blade at the same point, you have enough information to

calculate the pitch angle. Alternatively read the result from the table below which gives a

rough approximationhttp://easycalculation.com/trigonometry/triangle-angles.php

Width of blade 1.5 cm gap 2 cm gap 3 cm gap

21 cm (scull) 4 degrees 5.5 degrees 8 degrees

25 cm (sweep) 3.5 degrees 4.5 degrees 7 degrees

It is often the case that equipment used by less experienced crews is older and likely to

be worn or suffering from damage that results in the pitch being incorrect so do check

it. If it is badly out, there are five possibilities:

The swivels have the wrong pitching inserts fitted

The pin is not vertical (possibly because the rigger is bent)

The swivel is badly worn

The sleeve on the blade is badly worn

The blade is twisted (common in wooden blades but unlikely in modern composite

ones)

You should not attempt to put these right without permission, and also without the help

of a person who has experience of rigging. However, there is a quick fix if only a slight

adjustment is required. This is to wind some electricians tape around the top of the

swivel to increase pitchand at the bottom to decrease it.
http://easycalculation.com/trigonometry/triangle-angles.phphttp://easycalculation.com/trigonometry/triangle-angles.php


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What is critical is that the pitch is the same on a set of sculling blades or on bow side

and stroke side sweep oars. A different pitch angle on bow side or stroke side can

make the boat uncomfortable to row.

Incidentally, most UK coaches check the pitch at the swivel whereas in other countries

the pitch is checked at the end of the blade.

7. Pin Pitch

The pin that the swivel rotates around should be vertical (0 degrees) relative to the

length of the boat (stern pitch). The lateral pitch that is relative to a horizontal line

across the boat should be between 0 degrees (vertical) and 1 degree away from the

centre line of the boat.

A slight amount of lateral pitch changes the stern pitch throughout the stroke. It will

increase it at the catch and reduce it at the finish. A detailed discussion of lateral pitch

is beyond the scope of this article. But do check it! I have seen pins with about 10

degrees of lateral pitch.

Checking the pitch of the pinwith the boat set up to be horizontal


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When you visit your doctor these days, the chances are that you will have a discussion

about the problem and the various treatment options. This is because the ethos in

medical training is now patient centred. Similarly, the training of coaches is now

participant focused so hopefully your coach will be prepared to have a discussion with

you about how changes to the rigging might help to improve your comfort and technique.

When you have achieved a greater degree of comfort, the next task is to tune the

rigging so that you make more effective use of your muscular skeletal system to make

the boat go faster.

Rigging is about optimising a range of variables that interact with each other the

biggest variable being the rower. The chances are that you are still confused about

aspects of rigging, but hopefully your confusion is at a higher level than before!


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About the Author

Jim Flood is a coach for the International Olympic Committee Coach

Development Programme as well as Reading Rowing Club. He also occasionally

coaches at Malmo Rowing Club in Sweden and is a consultant coach for FISA.

He has been a consultant on the British Rowing Level 2 Coaching Award and

has written Know the Game: Rowing. He is keen to see good practice in

coaching adapted from other sports who have developed further in this area.

For an online spreadsheet that gives you all the numbers for your height, weight

and experience, go to:

http://www.biorow.com/RigChart.aspx

For a useful set of general numbers go to:

http://www.rowingnz.com/Article.aspx?ID=1572

For further reading, try:

http://www.rowperfect.co.uk/shop/nuts-bolts-guide-to-rigging-e-book-162.html

(This book is out of print but available in e-book format)

For further queries, please contact the author on [email protected].

Rowperfect UK sells equipment, books, DVDs and tools for rowing and sculling

supporting excellence in technique and coaching.

We aim to sell products that help improve technical skills and deliver fast boats.

Our news page includes coaching advice, commentary from around the web

about the sport and product news, special offers and promotions.

Get in touch if you would like us to sponsor and support your rowing club school

or university team.
http://www.biorow.com/RigChart.aspxhttp://www.rowingnz.com/Article.aspx?ID=1572http://www.rowperfect.co.uk/shop/nuts-bolts-guide-to-rigging-e-book-162.htmlhttp://www.rowperfect.co.uk/shop/nuts-bolts-guide-to-rigging-e-book-162.htmlhttp://www.rowingnz.com/Article.aspx?ID=1572http://www.biorow.com/RigChart.aspx

the ergonomics of rowing

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