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It's IN The Computer: A No-Nonsense Breakdown of Rowing Tech Jargon

Feeling a little lost when others are slinging around rowing jargon? Here are over 40 rowing terms and their definition to help you fit in better at parties and in the boat house.

Arc Length:

In rowing, arc length is the amount of distance the oar handle travels between the catch and the finish. This is different from stroke length which, in terms of the Empower Oarlock system, is the number of degrees the oar shaft rotates between the catch and the finish.

Average Power:

Power per stroke averaged over the entire interval (if using a SpeedCoach). Resetting the clock will also reset the average power.

Average Speed:

Instantaneous speed averaged over the entire interval (if using a SpeedCoach). Resetting the clock will also reset the average speed.

Average Work:

Work per stroke averaged over the entire interval (if using a SpeedCoach). Resetting the clock will also reset the average work.

Bluetooth® Low Energy (BLE):

An energy-efficient version of the traditional Bluetooth® technology. BLE allows your EmPower Oarlock to communicate with your SpeedCoach GPS 2 and your SpeedCoach GPS 2 to communicate with your mobile device using very little power. Using BLE instead of another system such as Ant+ means NK electronics can last longer on a single charge with smaller batteries.

Box Plot:

A type of plot used in descriptive statistics that shows the minimum and maximum of a data set, plus the first quartile, the third quartile and the median. It is useful for organizing multiple data sets (such as multiple workouts where there is data from each stroke in the workout).

Catch:

In terms of the

EmPower Oarlock system, catch is defined as the point in the stroke before the drive where the oar changes direction.

Catch Angle:

The angle, at the catch, between the oar shaft and an imaginary line running perpendicular to the centerline of the boat. Catch angle is measured in degrees and by convention is expressed as a negative value.

Classic Screen:

The traditional SpeedCoach GPS screen with four windows. Information from a heart rate monitor and/or an EmPower Oarlock may be placed in any of these windows. Note: when using the programmable workout function on the SpeedCoach, the bottom left window will default to distance for distance-based intervals and chrono for time-based intervals.

Critical Power:

The threshold of fatigue under which physiological responses to exertion can be stabilized. In rowing this translates to how hard you can pull for a given length of time. NK partner Sander Roosendaal has developed a system for calculating critical power using the EmPower Oarlock.

CSV (.csv) File:

CSV stands for comma-separated values. Files in this format can be easily imported to and exported from programs that organize data into tables, such as Microsoft Excel or Numbers on macOS. Any SpeedCoach data (which includes EmPower Oarlock data) that you transfer from the NK LiNK app to another program can be sent as a CSV or .fit file.

Distance per Stroke:

The distance the boat travels between each catch. At a given rate, distance per stroke is an important metric for gauging the efficiency of the stroke as a whole.

Dongle (USB Dongle):

A small USB device that allows the SpeedCoach to upload information directly to a computer.

Effective (Stroke) Length:

The number of degrees the oar shaft rotates between the catch and the finish where the load on the blade is greater than 100 newtons for sculling or 200 newtons for sweep; the portion of the drive where the blade is engaged.Effective length can be calculated as total length minus slip and wash.

EmPower Oarlock:

NK's smart oarlock. Measures catch angle, slip, power, wash and finish angle. Data from each Oarlock is displayed and stored on a SpeedCoach GPS 2 with Training Pack.

Training Pack:

A software upgrade to the SpeedCoach GPS 2 that makes it compatible with the EmPower Oarlock. The Training Pack also allows you to program any workout into the SpeedCoach GPS 2 so you can better organize your time on the water and get more accurate data from each interval (without the training pack, the SpeedCoach saves data in 100m, 0.1mi or 30s increments).

Finish:

In terms of the EmPower Oarlock system, the point in the stroke after the drive where the oar changes direction.

Finish Angle:

The angle, at the finish, between the oar shaft and an imaginary line running perpendicular to the centerline of the boat. Finish angle is measured in degrees and by convention is expressed as a positive value.

FIT (.fit) File:

A type of file used by the SpeedCoach and NK LiNK app. FIT files can contain information about location and time logged by the SpeedCoach or other GPS device during training and racing and can be uploaded to Strava or other similar web service for personal fitness tracking.

Force:

Measured by the EmPower Oarlock using a strain gauge located in the core of the Oarlock.

Inboard:

The length from the end of the oar handle to the outside of the collar where it touches the oarlock. http://www.concept2.com/service/oars/setting-inboard

IP67:

IP stands for “International Protection” marking. All NK products are dustproof and waterproof to the IP67 standard, which means they are dust proof can be submerged one meter underwater for at least 30 minutes.

Joules:

Unit of energy or work.

Length:

Same as stroke length: the number of degrees the the oar shaft rotates between the catch and the finish.

LiNK App:

Available for both iOS and Android. Allows your mobile device to receive wireless uploads from your SpeedCoach GPS 2 so you can store and organize data from your workouts. This information can be viewed in 100-meter, 0.1-mile, and 30-second increments, and can be exported as .fit or .csv files to popular workout management programs such as Strava. All uploaded sessions are saved on your smart device allowing you to safely clear your SpeedCoach memory and record new sessions.

Lock:

In terms of the EmPower Oarlock system, lock is defined as the moment (or the angle of the oar shaft) when the blade fully engages with the water after the catch. For continuity, lock threshold has been assigned a fixed value of 200 newtons for sweep rowing and 100 newtons for sculling.

Max (Peak) Force:

The maximum amount of force placed on the handle during a given stroke.

Max (Peak) Force Angle:

The angle between the oar shaft and an imaginary line running perpendicular to the centerline of the boat at the moment peak force is reached.

Mechanical Advantage:

The amplification of force achieved by using a tool (such as an oar).

NiMH (batteries):

A type of rechargeable battery recommended for use in the EmPower Oarlock. NiMH stands for nickel-metal hydride.

Oar Length:

Measured from the tip of the handle to the center of the blade edge. When setting up your EmPower Oarlock, it is important to

Pin Size:

The diameter of the vertical metal pin that holds the oarlock. Nearly every boatbuilder uses pins that are either 13 mm, 1/2" or 7/16".

Pitch:

The number of degrees the pin tilts (relative to vertical). The EmPower Oarlock has four degrees of positive lateral pitch (i.e. tilts four degrees outward from the boat).

Power:

Work per unit of time. In rowing, power is the Work per Stroke divided by Time per Stroke. While we use Work per Stroke as calculated on the drive, we use the Time per Stroke for the entire stroke cycle. This is done to account for physiological recovery which occurs during the stroke cycle, whereas the work is done primarily on the drive.

Rowsandall:

A "freemium" style rowing analytics platform created by Sander Roosendaal.

Skill Screen:

Available views for the SpeedCoach GPS 2 when used with the EmPower Oarlock. The major metrics provided by the Oarlock have been organized into five categories, or skills: Catch (which has two windows, one for catch angle and one for slip), Finish (two windows, finish angle and wash), Length (three windows, catch angle, finish angle and total length), Power (two windows, power and average power) and Work (three windows, work, force and length).

Slip:

The number of degrees the oar shaft rotates after the catch before the blade engages with (locks onto) the water. The engagement, or "lock" threshold has been assigned a fixed value of 200 newtons for sweep rowing and 100 newtons for sculling.

SpeedCoach:

NK's original on-the-water performance monitor for rowing. The latest model of the SpeedCoach is the SpeedCoach GPS 2, which can measure speed using GPS or (more accurately) using an impeller mounted to the hull of the boat. This is the first model of the SpeedCoach with updatable firmware and the only model that is compatible with the EmPower Oarlock (note: Training Pack, the software upgrade available for purchase with the SpeedCoach GPS 2, must be installed for the SpeedCoach to be compatible with the EmPower Oarlock).

Strain Gauge:

The mechanism that measures the force placed on the EmPower Oarlock.

Stroke Length:

Same as length: the number of degrees the the oar rotates between the catch and the finish.

Training Pack:

The software upgrade available for purchase with the SpeedCoach GPS 2. With the Training Pack, any workout can be programmed into the SpeedCoach GPS 2 for use on the water.

Unlock:

In terms of the EmPower Oarlock system, unlock is defined as the moment the blade disengages from the water before the finish. For continuity, (un)lock threshold has been assigned a fixed value of 200 newtons for sweep rowing and 100 newtons for sculling.

Wash:

The number of degrees the oar shaft rotates before the finish after the blade disengages (unlocks) from the water. The engagement, or "lock" threshold has been assigned a fixed value of 200 newtons for sweep rowing and 100 newtons for sculling.

Watts:

Unit of power.

Work:

Force times distance, measured in Joules. In rowing, work per stroke is the average force on the oar handle during the drive multiplied by the distance the handle travels from catch to finish.