Home Page | Notizie | Sui giornali | Risultatì 2006 | Calendario
La Società
 Physics of Rowing

Prepared by Dr. A. Dudhia mailto:dudhia@atm.ox.ac.uk Dept. Atmospheric Physics, Oxford University, an ARA Silver Level coach and surprisingly slow sculler from St.Catherine's College BC

Recent modifications:
  • 25-SEP-98 Add Relationship between Erg Score and Boat Speed
  • 18-SEP-98... Start adding the actual FAQs appropriate to each section
  • 12-SEP-98... Start tidying up references and adding relevant links within each section
None of the following information is copyright, so feel free to reproduce any or all of it, credited or uncredited as you see fit (although I might be a bit miffed if anyone else tried to pass it off as their own work).

Contents of this page

  • Rowing FAQ (Hannes Hofer) covers a lot of the terminology used here


  1. Propulsion
    • Why does the blade have to slip in the water? (when it doesn't if you push off a solid object?)
  2. Resistance
    • What causes a boat to slow down?
    • Why don't you go twice as fast if you pull twice as hard?
  3. Kinetic Energy
    • Why are 'cleavers' a good idea ? (when you can get the same impulse from smaller blades?)
  4. Centre of Mass
    • Why do boats continue to accelerate (and move quickest) after the end of the stroke?
  5. Speed Variation
    • Why is it more efficient to row a piece with constant split-times?
    • Why is it more efficient to keep the hull speed as uniform as possible during the stroke?
    • Why were `sliding rigger' boats banned?
  6. Balance
    • Why do/don't boats balance?
    • Why is it easier to balance a moving boat?
  7. Levers
    • What type of lever is an oar?
    • Why does the boat move forwards although I'm pushing it backwards with my feet?
  8. Gearing
    • What is meant by the gearing of an oar?
    • Why is gearing expressed in terms of the span (or spread) rather than the inboard?
    • Why is changing the span 1cm supposed to be 3 times as effective as moving the button the same distance?
    • What are CLAMS and why are they used?
    • Why are cleavers shorter than the equivalent Macon oars?
  9. Newton's Laws of Motion

Influence of Weight

  1. Introduction
    • How do erg scores/boat speed depend on bodyweight?
  2. Relationship between Power and Weight
    • Why and how do Aerobic and Anaerobic power depend on weight?
  3. Power/Weight Ratios
    • How do Power/Weight ratios depend on weight?
  4. Relationship between Weight and Erg Speed
    • Why do heavier rowers have an advantage on Erg scores
    • Where does the 2/9 (or 0.222) exponent come in erg-conversion scores come from?
  5. Relationship between Weight and Boat Speed
    • Why are heavier rowers faster than lighter rowers?
    • Why is this difference less obvious over long distances?
  6. Speeds of different Boat Classes
    • Why are boats with more rowers faster?
    • How much faster are they?
    • How fast should an octuple scull be?
  7. Effect of deadweight
    • What is the effect of deadweight on boat speed?
    • How much does the weight of the cox affect the boat speed?
  8. Relationship between Erg Score and Boat Speed
    • How do you convert erg-scores of rowers of different weights into equivalent boat speed?
    • If I lose weight, how much faster would I scull?
    • If I lose weight, how much should my erg score be allowed to drop in order to maintain the same boat speed?

Influence of Stream

  1. Introduction
    • Which feels `heavier': rowing upstream or downstream?
  2. Viscosity
    • What is viscosity?
    • Why is viscous drag said to be proportional to velocity?
  3. Boat Resistance
    • Why does boat resistance vary as velocity-squared? (when viscous drag is usually said to be proportional to velocity)
  4. River Flow
    • Why does a river flow quickest where it is deepest?
  5. Upstream/Downstream Resistance
    • Why does rowing upstream feel `lighter' than rowing downstream?
  6. Shallow Water Resistance
    • Why does rowing in shallow water feel heavier than deep water?
    • How shallow does water have to be before you notice?
  7. Upstream/Downstream times
    • Why is the average time for upstream + downstream pieces slower when the stream is faster? (when you'd expect the stream effect to cancel)

Physics of Ergometers

  1. Introduction
  2. Mechanics of Rotating Bodies
  3. Power Dissipation
  4. Power Supplied
  5. Changing the Cog
  6. Changing the Damping
  7. Measuring the Damping
  8. Measuring the Power Supplied
  9. Power v. Indicated Speed (Splits)
  10. Power v. Indicated Calories
  11. Dynamic v. Static Ergs
  12. Effect of Rating
  13. Effect of Altitude
  14. Glossary of terms used in Rotational Mechanics


A collection of other web-pages linked in the main text
Concept II
Concept II Web-Site
During, Alex (Univ. Oxford)
Alex' Guide to Rowing
Federation Internationale des Societes d'Aviron (FISA)
Rules of Racing
Kerr, Steve
Furnivall Sculling Club
Lazauskas, Leo (Univ. Adelaide)
A Performance Prediction Model for Rowing Races
Martin, Jeremy (Univ. Oxford)
Pomponi, Renata (MIT)
Seiler, Stephen (Agder College, Norway)
Rowing Physiology and Performance
Virginia Tech
Rowing Rigger Design
Young, Ken (Univ. Washington)
Physics of Sport

Other Relevant Web Resources

(please inform me if you know of any other relevant Websites).


I would like to thank the following for their help in the creation of these web pages:
Marinus van Holst, Dick Nixon, ... [plus others whom I will get around to adding]
Anu Dudhia (dudhia@atm.ox.ac.uk)
© 1999 - 2006 S.C. Pallanza - All Rights Reserved