Swimming

Swimming is a form of transportation that allows the player to move in water.

Control
Swimming is activated by pressing while in water.

Sprint-swimming can also be activated. To do this, the player can press for 1 block gap while moving, or double tap. The player cannot sprint-swim if their hunger bar is at or below.

Sneaking when swimming will allow the player to sink faster.

Usage
When swimming on the surface of still water, the player will move at 2.20 blocks per second. If the player is partially submerged in water, they will move at 1.97 blocks per second. The player will move at 1.81 blocks per second when swimming downstream underwater, and will move at a slower 0.39 blocks per second while swimming upstream underwater.

Sprint-swimming
Sprint-swimming allows the player to move at around 5.612 meters/second, which is 30 percent faster than the normal walking speed of around 4.317 m/s. The player can turn while sprint-swimming, which will slightly reduce their speed. Sprint-swimming will also increase the speed of flying in Creative mode. Although while sprint-swimming increases the field of vision like actual sprinting, it does not increase the entity's speed. However, one can accelerate by pressing the boost button.

Sneaking while sprint-swimming will allow the player to descend downwards even faster.

With sprinting while swimming, it is possible to swim across the water horizontally, instead of the usual two blocks, though sprinting will not cause the player to swim higher.

Sprint-swimming will reduce the player's saturation, and once their saturation is 0 it will deplete the hunger bar at a rate of $1/2$ every 40 meters, or 7 seconds.

When a player attacks any mob (excluding squid, fish mobs, and turtles) while sprint-swimming, the mob suffers a larger knockback than usual.

Sprint-swimming, like normal sprinting, ends when the player collides with a solid block, sneaks, blocks or attacks a mob. Additionally, sprint-swimming will also end if the hunger bar lowers to or below.

Trivia

 * Sprinting and jumping while under a 1 block gap high ceiling causes a player to move at a speed almost twice as fast as regular sprinting speed, but it will consume a hunger point every second.
 * This can be sped up even more by decreasing the ceiling height using water source or by sprinting on ice.
 * A similar effect occurs if the player sprints and rapidly hits at the same time on a set on fish mobs.