THL: Stay a safe distance from vertical surfaces if there are significant waves present in the area. A passing boat or ship may generate big waves that escape your attention until there is no time to escape. An example is the North anchorage of the Golden Gate Bridge (but there are special cases, e.g. rough water classes or the OWRC regatta, when there is a fast flood coming through the Golden Gate, and it is useful to be close to the wall since the current is slower there).
The recovery phase follows the drive. The recovery starts with the extraction and involves coordinating the body movements with the goal to move the oar back to the catch position. In extraction, the rower pushes down on the oar handle to quickly lift the blade from the water and rapidly rotates the oar so that the blade is parallel to the water. This process is sometimes referred to as feathering the blade. Simultaneously, the rower pushes the oar handle away from the chest. The blade emerges from the water square and feathers immediately once clear of the water. After feathering and extending the arms, the rower pivots the body forward. Once the hands are past the knees, the rower compresses the legs which moves the seat towards the stern of the boat. The leg compression occurs relatively slowly compared to the rest of the stroke, which affords the rower a moment to recover, and allows the boat to glide through the water. The gliding of the boat through the water during recovery is often called run.
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.
While rowing, the athlete sits in the boat facing toward 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 canal, river, lake, sea, or other large bodies of water. The sport requires strong core balance, physical strength, flexibility, and cardiovascular endurance.
Rowers may take part in the sport for their leisure or they may row competitively. There are different types of competition in the sport of rowing. In the U.S. all types of races are referred to as regattas whereas this term is only used in the UK for head-to-head or multi-lane races (such as those that take place at Dorney Lake), which generally take place in the summer season. Time trials occur in the UK during the winter, and are referred to as Head races. In the US, head races (usually about 5k, depending on the body of water) are rowed in the fall, while 2k sprint races are rowed in the spring and summer.