Indoor rower

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Several Concept 2 Model C indoor rowers

An indoor rower, or rowing machine, is a machine used to simulate the action of watercraft rowing for the purpose of exercise or training for rowing. Indoor rowing has become established as a sport in its own right. The term also refers to a participant in this sport.

Modern indoor rowers are often known as ergometers (colloquially erg or ergo), an ergometer being a device which measures the amount of work performed. The indoor rower is calibrated to measure the amount of energy the rower is using through their use of the equipment. Typically the display of the ergometer (e.g. on a concept2) will show the time it takes to row 500m at each strokes power. This is known as the split rate, or split. The decision to show the time to complete 500m is due to the standard rowing distance is 2000m, which is 4 stretches of 500m.

History[edit]

Chabrias, an Athenian admiral of the 4th century BC, introduced the first rowing machines as supplemental military training devices. "To train inexperienced oarsmen, Chabrias built wooden rowing frames on shore where beginners could learn technique and timing before they went on board ship."[1]

Early rowing machines are known to have existed from the mid-1800s, a US patent being issued to W.B. Curtis in 1872 for a particular hydraulic based damper design. Machines using linear pneumatic resistance were common around 1900—one of the most popular was the Narragansett hydraulic rower, manufactured in Rhode Island from around 1900–1960.[2] However they did not simulate actual rowing very accurately nor measure power output.[citation needed]

In the 1950s and 1960s, coaches in many countries began using specially made rowing machines for training and improved power measurement.[citation needed] One original design incorporated a large, heavy, solid iron flywheel with a mechanical friction brake, developed by John Harrison of Leichhardt Rowing Club in Sydney, later to become a professor of mechanical engineering at the University of New South Wales.[citation needed] Harrison, a dual Australian champion beach sprinter who went on to row in the coxless four at the 1956 Melbourne Olympics, had been introduced to rowing after a chance meeting with one of the fathers of modern athletic physiological training and testing, and the coach of the Leichhardt Guinea Pigs, Professor Frank Cotton.[citation needed] Cotton had produced a rudimentary friction-based machine for evaluating potential rowers by exhausting them, without any pretence of accurately measuring power output.[citation needed] Harrison realised the importance of using a small braking area with a non-absorbent braking material, combined with a large flywheel.[citation needed] The advantage of this design (produced by Ted Curtain Engineering, Curtain being a fellow Guinea Pig) was the virtual elimination of factors able to interfere with accurate results—for instance ambient humidity or temperature.[citation needed] The Harrison-Cotton machine represents the very first piece of equipment able to accurately quantify human power output; power calculation within an accuracy range as achieved by his machine of less than 1% remains an impressive result today. The friction brake was adjusted according to a rower's weight to give an accurate appraisal of boat-moving ability (drag on a boat is proportional to weight)[citation needed]. Inferior copies of Harrison's machine were produced in several countries utilising a smaller flywheel and leather straps—unfortunately the leather straps were sensitive to humidity, and the relatively large braking area made results far less accurate than Harrison's machine.[citation needed] The weight correction factor tended to make them unpopular among rowers of the time. Harrison, arguably the father of modern athletic power evaluation, died in February 2012.[3]

Gjessing-Nilson rowing ergometer, showing helical pulley and flywheel

In the 1970s, the Gjessing-Nilson ergometer from Norway used a friction brake mechanism with industrial strapping applied over the broad rim of the flywheel. Weights hanging from the strap ensured that an adjustable and predictable friction could be calculated. The cord from the handle mechanism ran over a helical pulley with varying radius, thereby adjusting the gearing and speed of the handle in a similar way to the changing mechanical gearing of the oar through the stroke, derived from changes in oar angle and other factors. This machine was for many years the internationally accepted standard for measurement.[citation needed]

The first air resistance ergometers were introduced around 1980 by Repco.[citation needed]

In 1981, Peter and Richard Dreissigacker, and Jonathan Williams, filed for U.S. patent protection, as joint inventors of a "Stationary Rowing Unit". The patent was granted in 1983 (US 4396188A). The first commercial embodiment of the Concept2 "rowing ergometer" (as it came to be known) was the Model A, a fixed-frame sliding-seat design using a bicycle wheel with fins attached for air resistance. The Model B, introduced in 1986, introduced a solid cast flywheel (now enclosed by a cage) and the first digital performance monitor, which proved revolutionary. This machine's capability of accurate calibration combined with easy transportability spawned the sport of competitive indoor rowing, and revolutionised training and selection procedures for watercraft rowing. Later models were the C (1993) and D (2003).[2][4]

In 1995, Casper Rekers, a Dutch engineer, was granted a U.S. patent for a (US 5382210A) "Dynamically Balanced Rowing Simulator". This device differed from the prior art in that the flywheel and footrests are fixed to a carriage, the carriage being free to slide fore and aft on a rail or rails integral to the frame. The seat is also free to slide fore and aft on a rail or rails integral to the frame. From the patent Abstract: "During exercise, the independent seat and energy dissipating unit move apart and then together in a co-ordinated manner as a function of the stroke cycle of the oarsman."[citation needed]

Design summary[edit]

All rowing-machine designs consist of an energy damper or braking mechanism connected to a chain, strap, belt and/or handle. Footrests are attached to the same mounting as the energy damper. Most include a rail which either the seat or the mechanism slide upon. Different machines have a variety of layouts and damping mechanisms, each of which have certain advantages and disadvantages.

Currently available ergometer (flywheel-type) rowing machines use a spring or elastic cord to take up the pull chain/strap and return the handle. Advances in elastic cord and spring technology have contributed to the longevity and reliability of this strategy, but it still has disadvantages. With time and usage, an elastic element loses its strength and elasticity. Occasionally it will require adjustment, and eventually it will no longer take up the chain with sufficient vigour, and will need to be replaced. The resilience of an elastic cord is also directly proportional to temperature. In an unheated space in a cold climate, an elastic cord equipped rowing ergometer is unusable because the chain take-up is too sluggish. Thus, as the result of several factors, the force required to stretch the elastic cord is a variable, not a constant. This is of little consequence if the exercise device is used for general fitness, but it is an unacknowledged problem, the "dirty little secret", of indoor rowing competitions. The electronic monitor only measures the user input to the flywheel. It does not measure the energy expenditure to stretch the elastic cord. A claim of a "level playing field" cannot be made when a resistance variable exists (that of the elastic cord) which is not measured or monitored in any way (see more on this in "Competitions" section).

In the patent record, means are disclosed whereby the chain/cable take-up and handle return are accomplished without the use of a spring or elastic cord, thereby avoiding the stated disadvantages and defects of this broadly used method. One example is the Gjessing-Nilson device described above. Partially discernable in the thumbnail photo, it utilizes a cable wrapped around a helical pulley on the flywheel shaft, the ends of this cable being connected to opposite ends of a long pole to which a handle is fixed. The obvious disadvantage of this system is the forward space requirement to accommodate the extension of the handle pole at the "catch" portion of the stroke. The advantage is that, except for small transmission losses, all of the user's energy output is imparted to the flywheel, where it can be accurately measured, not split between the flywheel and an elastic cord of variable, unmeasured resistance. If a similar system were installed on all rowing ergometers used in indoor rowing competitions, consistency between machines would be guaranteed because the variability factor of elastic cord resistance would be eliminated, and this would therefore ensure that the monitor displayed actual user energy input.

In a 1988 US patent (US 4772013A), Elliot Tarlow discloses another non-elastic chain/cable take-up and handle return strategy. Described and depicted is a continuous chain/cable loop that passes around the flywheel sprocket and around and between fixed pulleys and sprockets positioned fore and aft on the device. The handle is secured in the middle of the exposed upper horizontal section of the chain/cable loop. Although somewhat lacking in aesthetics, the Tarlow device does eliminate the stated disadvantages and defects of the ubiquitous elastic cord handle return. Tarlow further argues that the disclosed method provides an improved replication of rowing because in actual rowing the rower is not assisted by the contraction of a spring or elastic cord during the "recovery" portion of the stroke. The rower must push the oar handle forward against wind and oarlock resistance in preparation for the next stroke. Tarlow asserts that the invention replicates that resistance.

A third non-elastic handle return strategy is disclosed in US patent, "Gravity Return Rowing Exercise Device" (US9878200 B2, 2018) granted to Robert Edmondson. As stated in the patent document, the utilization of gravity (i.e.: a weight) to take up the chain and return the handle eliminates the inevitable variability of handle return force associated with an elastic cord system and thereby ensures consistency between machines.

Machines with a digital display calculate the user's power by measuring the speed of the flywheel during the stroke and then recording the rate at which it decelerates during the recovery. Using this and the known moment of inertia of the flywheel, the computer is able to calculate speed, power, distance and energy usage. Some ergometers can be connected to a personal computer using software, and data on individual exercise sessions can be collected and analysed. In addition, some software packages allows users to connect multiple ergometers either directly or over the internet for virtual races and workouts.

Motion type[edit]

At the current state of the art, indoor rowers which utilize flywheel resistance can be categorized into two motion types. In both types, the rowing movement of the user causes the footrests and the seat to move further and closer apart in co-ordination with the user's stroke. The difference between the two types is in the movement, or absence of movement, of the footrests relative to ground.

The first type is characterized by the Dreissigacker/Williams device (referenced above). With this type the flywheel and footrests are fixed to a stationary frame, and the seat is free to slide fore and aft on a rail or rails integral to the stationary frame. Therefore, during use, the seat moves relative to the footrests and also relative to ground, while the flywheel and footrests remain stationary relative to ground.

The second type is characterized by the Rekers device (referenced above). With this type, both the seat and the footrests are free to slide fore and aft on a rail or rails integral to a stationary frame. Therefore, during use, the seat and the footrests move relative to each other, and both also move relative to ground.

Damper type[edit]

Piston resistance comes from hydraulic cylinders that are attached to the handles of the rowing machine.[5] The length of the rower handles on this class of rower is typically adjustable, however, during the row the handle length is fixed which in turn fixes the trajectory that the hands must take on the stroke and return, thus making the stroke less accurate than is possible on the other types of resistance models where it is possible to emulate the difference in hand height on the stroke and return.[citation needed] Furthermore, many models in this class have a fixed seat position that eliminates the leg drive which is the foundation of competitive on water rowing technique.[citation needed] Because of the compact size of the pistons and mechanical simplicity of design, these models are typically not as large or as expensive as the others types.[citation needed]

Braked flywheel resistance models comprise magnetic, air and water resistance rowers.[citation needed] These machines are mechanically similar since all three types use a handle connected to a flywheel by rope, chain, or strap to provide resistance to the user – the types differ only in braking mechanism.[citation needed] Because the handle is attached to the resistance source by rope or similarly flexible media, the trajectory of the hands in the vertical plane is free making it possible for the rower to emulate the hand height difference between the stroke and the return.[citation needed] Most of these models have the characteristic sliding seat typical of competitive on-the-water boats.[citation needed]

Magnetic resistance models control resistance by means of permanent magnets or electromagnets.[6][5] A rotary plate, made of non-magnetic, electrical conducting material such as aluminum or copper, and either integral with, or independent of the flywheel, cuts through the magnetic field of the permanent magnet or the electromagnet, resulting in induced eddy currents which generate a retarding force that opposes the motion of the rotary plate.[citation needed] Resistance is adjusted with the permanent magnet system by changing the position of the permanent magnet relative to the rotary plate.[7][8] Resistance is adjusted with the electromagnetic system by varying the strength of the electromagnetic field through which the rotary plate moves.[9] The magnetic braking system is quieter than the other braked flywheel types and energy can be accurately measured on this type of rower.[citation needed] The drawback of this type of resistance mechanism is that the resistance is constant for any given setting.[citation needed] Rowers using air or water resistance more accurately simulate actual rowing, where the resistance increases the harder the handle is pulled.[citation needed] Some rowing machines incorporate both air and magnetic resistance.[citation needed]

Air resistance models use vanes on the flywheel to provide the flywheel braking needed to generate resistance.[5] As the flywheel is spun faster, the air resistance increases.[citation needed] An adjustable vent can be used to control the volume of air moved by the vanes of the rotating flywheel, therefore a larger vent opening results in a higher resistance, and a smaller vent opening results in a lower resistance.[citation needed] The energy dissipated can be accurately calculated given the known moment of inertia of the flywheel and a tachometer to measure the deceleration of the flywheel.[citation needed] Air resistance rowing machines are most often used by sport rowers (particularly during the off season and inclement weather) and competitive indoor rowers.[citation needed]

Water resistance models consist of a paddle revolving in an enclosed tank of water.[5] The mass and drag of the moving water creates the resistance.[citation needed] Proponents claim that this approach results in a more realistic action than possible with air or magnetic type machines. "WaterRower" was the first company to manufacturer this type of rowing machine. The company was formed in the 1980s by John Duke, a US National Team rower, and inventor of the device (1989 US Patent US 4884800A ). At that time, in the patent record, there were a few prior art fluid resistance rowing machines, but they lacked the simplicity and elegance of the Duke design. From the 1989 patent Abstract: "... rowing machine features a hollow container that holds a supply of water. Pulling on a drive cord during a pulling segment of a stroke rotates a paddle or like mechanism within the container to provide a momentum effect."[citation needed]

Exercise[edit]

Indoor rowing primarily works the cardiovascular systems with typical workouts consisting of steady pieces of 20–40 minutes, although the standard trial distance for record attempts is 2000 m, which can take from five and a half minutes (best elite rowers) to nine minutes or more. Like other forms of cardio focused exercise, interval training is also commonly used in indoor rowing. While cardio-focused, rowing also stresses many muscle groups throughout the body anaerobically, thus rowing is often referred to as a strength-endurance sport.

The standard measurement of speed on an ergometer is generally known as the "split", or the amount of time in minutes and seconds required to travel 500 metres (1,600 ft) at the current pace — a split of 2:00 represents a speed of two minutes per 500 metres, or about 4.17 m/s (15.0 km/h).

Ergometer testing[edit]

Although ergometer tests are used by rowing coaches to evaluate rowers and are part of athlete selection for many senior and junior national rowing teams, "the data suggest that physiological and performance tests performed on a rowing ergometer are not good indicators of on water performance".[10]

Rowing technique[edit]

Rowing technique on the erg broadly follows the same pattern as that of a normal rowing stroke on water, but with minor modifications: it is not necessary to "tap down" at the finish, since there are no blades to extract from water; but many who also row on water do this anyway. Also, the rigid, single-piece handle enables neither a sweep nor a sculling stroke. The oar handle during a sweep stroke follows a long arc, while the oar handles during a sculling stroke follow two arcs. The standard handle does neither. But regardless of this, to reduce the chance of injury, an exercise machine should enable a bio-mechanically correct movement of the user. The handle is the interface between the human and the machine, and should adapt to the natural movement of the user, not the user to the machine, as is now the case. During competitions an exaggerated finish is often used, whereby the hands are pulled further up the chest than would be possible on the water, resulting in a steep angulation of the wrists - but even with a normal stroke, stop-action images show wrist angulation at the finish, evidence that the standard rigid, single-piece handle does not allow the user to maintain a bio-mechanically correct alignment of hands, wrists, and forearms in the direction of applied force. On the Concept 2 website "Forum", many regular users of the indoor rower have complained of chronic wrist pain. Some have rigged handgrips with flexible straps to enable their hands, wrists, and forearms to maintain proper alignment, and thereby reduce the possibility of repetitive strain injury. Rowing machine manufacturers have ignored this problem.

Rowing on an ergometer requires four basic phases to complete one stroke; the catch, the drive, the finish and the recovery. The catch is the initial part of the stroke. The drive is where the power from the rower is generated while the finish is the final part of the stroke. Then, the recovery is the initial phase to begin taking a new stroke. The phases repeat until a time duration or a distance is completed.

Catch[edit]

Knees are bent with the shins in a vertical position. The back should be roughly parallel to the thigh without hyperflexion (leaning forward too far). The arms and shoulders should be extended forward and relaxed. The arms should be level.

Drive[edit]

The drive is initiated by the extension of the legs; the body remains in the catch posture at this point of the drive. As the legs continue to full extension, the rower engages the core to begin the motion of the body levering backward, adding to the work of the legs. When the legs are flat, the rower begins to pull the handle toward the chest with their arms while keeping their arms straight and parallel to the floor.

Finish (or release)[edit]

The legs are at full extension and flat. The shoulders are slightly behind the pelvis, and the arms are in full contraction with the elbows bent and hands against the chest below the nipples. The back of the rower is still maintained in an upright posture and wrists should be flat.

Recovery[edit]

The recovery is a slow slide back to the initial part of the stroke, it gives the rower time to recover from the previous stroke. During the recovery the actions are in reverse order of the drive. The arms are fully extended so that they are straight. The torso is engaged to move forward back over the pelvis. Weight transfers from the back of the seat to the front of the seat at this time. When the hands come over the knees, the legs contract back towards the foot stretcher. Slowly the back becomes more parallel to the thighs until the recovery becomes the catch.

Competitions[edit]

The first indoor rowing competition was held in Cambridge, MA in February 1982 with participation of 96 on-water rowers who called themselves the "Charles River Association of Sculling Has-Beens".[11] Thus the acronym, "CRASH-B". A large number of indoor rowing competitions are now held worldwide, including the indoor rowing world championships (still known as CRASH-B Sprints) held in Boston, Massachusetts, United States in February and the British Indoor Rowing Championships held in Birmingham, England in November, or in more recent years the Lee Valley VeloPark London in December; both are rowed on Concept2s. The core event for most competitions is the individual 2000-m; less common are the mile (e.g., Evesham), the 2500 meter (e.g., Basingstoke—also the original distance of the CRASH-B Sprints). Many competitions also include a sprint event (100–500m) and sometimes team relay events.

Most competitions are organized into categories based on sex, age, and weight class. While the fastest times are generally achieved by rowers between 20 and 40 years old, teenagers and rowers over 90 are common at competitions. There is a nexus between performance on-water and performance on the ergometer, with open events at the World Championships often being dominated by elite on-water rowers. Former men's Olympic single scull champions Pertti Karppinen and Rob Waddell and five-time gold medalist Sir Steven Redgrave have all won world championships or set world records in indoor rowing. The British Graham Benton and the Italian Emanuele Romoli are two of the main "non-rower" that won several indoor rowing competitions.

In addition to live venue competitions, many erg racers compete by internet, either offline by posting scores to challenges, or live online races facilitated by computer connection. Online Challenges sponsored by Concept2 include the annual ultra-rowing challenge, the Virtual Team Challenge.[12]

See also[edit]

References[edit]

  1. ^ John R. Hale, "Lords of the Sea: The Epic Story of the Athenian Navy and the Birth of Democracy"
  2. ^ a b The Independent Rowing News, 22 February 2002, retrieved 3 February 2012
  3. ^ SA, WebSide Associates. "The Official World Rowing Web Site - Rowing / Ergometer/Indoor". wayback.archive.org. Archived from the original on 10 November 2006. Retrieved 15 May 2017.
  4. ^ "RowHist-Equipment". www.rowinghistory.net. Retrieved 15 May 2017.
  5. ^ a b c d "Rowing Machine Resistance Types". Rowing Machine Reviews 2017. Retrieved 7 August 2017.
  6. ^ Emerson, Heather M. J. "Air Vs. Magnetic Rowing Machine". Retrieved 7 August 2017.
  7. ^ "Simulated-kayak, upper-body aerobic exercise machine".
  8. ^ 1991 US Patent 5076573A "Magnetic Resistance Type Stationary Rowing Unit"
  9. ^ 1995 US Patent 5656001A "Eddy Current Trainer..."
  10. ^ Ed McNeely, The Sport Journal, Jan. 2, 2012
  11. ^ Concept 2 promotional booklet, year 2000
  12. ^ "Online Challenges". Concept2. Concept2. Retrieved February 6, 2015.