Rowing is a sport in which athletes race against each other on rivers, lakes or on the ocean, depending upon the type of race and the discipline. The boats are propelled by the reaction forces on the oar blades as they are pushed against the water. The sport can be both recreational, focusing on learning the techniques required, and competitive where overall fitness plays a large role. It is also one of the oldest Olympic sports. In the United States, high school and collegiate rowing is sometimes referred to as crew.
Basics
While rowing, the athlete sits in the boat facing backwards (towards the stern), and uses the oars which are held in place by the oarlocks to propel the boat forward (towards the bow). This may be done on a river, lake, sea, or other large body of water. It is a demanding sport requiring strong core balance as well as physical strength and cardiovascular endurance.[3]
Whilst the action of rowing and equipment used remains fairly consistent throughout the world, there are many different types of competition. These include endurance races, time trials, stake racing, bumps racing, and the side-by-side format used in the Olympic games. The many different formats are a result of the long history of the sport, its development in different regions of the world, and specific local requirements and restrictions.
There are two forms of rowing:
- In sweep or sweep-oar rowing, each rower has one oar, held with both hands. This can be done in pairs, fours and eights. Each rower in a sweep boat is referred to either as "port" or "starboard", depending on which side of the boat the rower's oar extends to. Usually the port side is referred to as stroke side, and the starboard side as bow side; this applies even if the stroke oarsman is rowing on bow side and/or the bow oarsman on stroke side.
- In sculling each rower has two oars (or sculls), one in each hand. Sculling is usually done without a coxswain, in quads, doubles or singles. The oar in the sculler's right hand extends to port (stroke side), and the oar in the left hand extends to starboard (bow side).
Anatomy of a stroke
The two fundamental reference points in the rowing stroke are the catch where the oar blade is placed in the water, and the extraction (also known as the 'finish' or the 'release') where the oar blade is removed from the water. The starting at the extraction, push the legs forward and finally bend the back as you slide forward on the rolling seat. After the rower places the blade in the water at the catch, he or she applies pressure to the back while simultaneously sliding the seat by extending the head. Making sure to keep the legs straight and let the back do the work for the first half of the stroke, then pulling the oars with the back and finally the arms as the last part of the stroke to the "finish". The part where pressure is applied is called the pain phase of the stroke, which occurs after the blade is vertically placed in the water. Once the rower extracts the oar from the water, the recovery phase begins, setting up the body for the next stroke.
Rowing propulsion
Rowing is a cyclic (or intermittent) form of propulsion and in the quasi-steady state the motion of the system (rower, oars and boat) is repeated regularly. In order for this perfectly cyclic motion to be maintained the sum all the external forces on the system, averaged over the cycle, must be zero, so that the system as a whole does not accelerate. In that case the average drag (retarding) force on the system must equal the average propulsion force on the system. The drag forces consists of aerodynamic drag on the superstructure of the system (everything above the waterline) and the hydrodynamic drag on the submerged portion of the system. The propulsion forces are the forward reaction of the water on the oars while in the water. Of course the oar can be used to provide a drag force (a force acting against the forward motion) when the system is brought to rest.
Although the oar can be conveniently thought of as a lever with a "fixed" pivot point in the water, the blade moves sideways and sternwards through the water, so that the magnitude of the propulsion force developed is the result of a complex interaction between unsteady fluid mechanics (the water flow around the blade) and solid mechanics and dynamics (the handle force applied to the oar, the oar's inertia and bending characteristic, the acceleration of the boat and so on).
Distinction from other watercraft
The distinction between rowing and other forms of water transport, such as canoeing or kayaking, is that in rowing the oars are held in place at a pivot point that is in a fixed position relative to the boat, this point acting as a fulcrum for the oar to act as a lever. In flatwater rowing, the boat (also called a 'shell' or 'fine boat') is narrow to avoid drag, and the oars are attached to oarlocks at the end of outriggers extending from the sides of the boat. Racing boats also have sliding seats to allow the use of the legs in addition to the body to apply power to the oar. Unlike canoes or kayaks, most racing shells are inherently unstable and require oars on either side to prevent them from rolling over.
Fitness and health
Rowing is one of the few non-weight bearing sports that exercises all the major muscle groups, including quads, biceps, triceps, lats, glutes and abdominal muscles. Rowing improves cardiovascular endurance and muscular strength. Rowing reduces fat but does not tend to build muscle in itself, though the associated weight training may do this. High-performance rowers tend to be tall and muscular: although extra weight does increase the drag on the boat, the larger athlete's increased power tends to be more significant.
Rowing is a low impact activity with movement only in defined ranges, so that twist and sprain injuries are rare. However, the repetitive rowing action can put strain on knee joints, the spine and the tendons of the forearm, and inflammation of these are the most common rowing injuries. If one rows with poor technique, other injuries may surface (back pains).
Equipment
Racing boats (often called "shells") are long, narrow, and broadly semi-circular in cross-section in order to reduce drag to a minimum. They usually have a fin towards the rear, to help prevent roll and yaw and to increase the effectiveness of the rudder.
Originally made from wood, shells are now almost always made from a composite material (usually carbon-fibre reinforced plastic) for strength and weight advantages. FISA rules specify minimum weights for each class of boat so that no individual will gain a great advantage from the use of expensive materials or technology.
There are several different types of boats. They are classified using:
- Number of rowers. In all forms of modern competition the number is either 1, 2, 4, or 8.
- Position of coxswain. Boats are either coxless ("straight"), bow-coxed (also called bowloaders), or stern-coxed.
Although sculling and sweep boats are generally identical to each other (except having different riggers), they are referred to using different names:
- Sweep: straight pair (or coxless pair) (2-), coxed pair (2+), straight four (or coxless four) (4-), coxed four (4+), eight (8+) (always coxed)
- Sculling: single (scull) (1x), double (scull) (2x), triple (scull) (3x) (very rare), quad (or quadruple) (scull) (4x), octuple (scull) (8x) (always coxed, and mainly for juniors and exhibition)
- Sweep/Sculling: Queep, 2 scullers and 2 sweepers (very rare)
With the smaller boats, specialist versions of the shells for sculling can be made lighter.
The riggers in sculling apply the forces symmetrically to each side of the boat, whereas in sweep oared racing these forces are staggered alternately along the boat. The sweep oared bo
at has to be stiffer to handle these unmatched forces, so consequently requires more bracing and is usually heavier - a pair (2-) is usually a more robust boat than a double scull (2x) for example, and being heavier is also slower when used as a double
scull. In theory this could also apply to the 4x and 8x, but most rowing clubs cannot afford to have a dedicated large hull which might be rarely used and instead generally opt for versatility in their fleet by using stronger shells which can be rigged for either sweep rowing or sculling. The symmetrical forces also make sculling more efficient than rowing: the double scull is faster than the coxless pair, and the qua
druple scull is faster than the coxless four. One additional boat is the 'Queep', a coxed or non-coxed shell. The bow and stroke positions have a set of sculling riggers and two and three have a sweep set. These shells have been used in the UK and recently at a club in Victoria BC, Canada.
Many adjustments can be made to the equipment to accommodate the physiques of the crew. Collectively these adjustments are known as the boat's rigging.
Steering
Single and double sculls are usually steered by the scullers pulling harder on one side or the other. In other boats there is a rudder, controlled by the cox, if present, or by one of the crew. In the latter case the rudder cable is attached to the toe of one of their shoes which can pivot about the ball of the foot, moving the cable left or right. The steersman may row at bow, who has the best vision when looking over their shoulder, or on straighter courses stroke may steer, since they can point the stern of the boat at some landmark at the start of the course. On international courses landmarks for steersmen, consisting of two aligned poles, are provided.
Oars
Oars are used to propel the boat. They are long (250–300 cm) poles with one flat end about 50 cm long and 25 cm wide, called the blade. Classic oars were made out of wood, but modern oars are made from synthetic material, the most common being carbon fiber.
An oar is often referred to as a "blade" in the case of sweep oar rowing and as a "scull" in the case of sculling. A sculling oar is shorter and has a smaller blade area than the equivalent sweep oar. The combined blade area of a pair of sculls is however greater than that of a single sweep oar, so the oarsman when sculling is working against more water than when rowing sweep-oared. He is able to do this because the body action in sculling is more anatomically efficient.
Indoor rowing
Ergometer rowing machines (colloquially ergs or ergo) simulate the rowing action and provide a means of training on land when waterborne training is restricted, and of measuring rowing fitness. Ergometers do not simulate the lateral balance challenges, the exact resistance of water, or the exact motions of true rowing including the sweep of the oar handles. For that reason ergometer scores are generally not used as the sole selection criterion for crews, and technique training is limited to the basic body position and movements. However, this action can still allow a comparable workout to those experienced on the water.
Indoor rowing has become popular as a sport in its own right with numerous indoor competitions (and the annual World Championship CRASH-B Sprints in Boston) during the winter off-season.
Boat storage and boathouses
Racing boats, usually together with oars, riggers, and other equipment for rowing, are stored in specially designed storage areas — or boathouses. These usually consist of a long two story building, in which the boats are stored on 'racks' (horizontal metal [usually] bars) on the ground floor with a large door at one end which most probably leads out to a pontoon on the river or lakeside. Other equipment is stored around the boats. Upstairs there is usually a gym, bar, an area for relaxation, etc. or very rarely more storage (due to difficulties transporting cumbersome rowing equipment upstairs).
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