Freediving , free- diving , free diving , breath-hold diving , or skin diving is a form of underwater diving that relies on divers' ability to hold their breath until resurfacing rather than on the use of a breathing apparatus such as scuba gear .
Besides the limits of breath-hold, immersion in water and exposure to high ambient pressure also have physiological effects that limit the depths and duration possible in freediving .
Examples of freedivingactivities are: traditional fishing techniques, competitive and non-competitive freediving , competitive and non-competitive spearfishing and freediving photography , synchronized swimming , underwater football , underwater rugby, underwater hockey , underwater target shooting and snorkeling . There are also a range of "competitive apnea" disciplines; in which competitors attempt to attain great depths, times, or distances on a single breath.
Historically, the term free diving was also used to refer to scuba diving , due to the freedom of movement compared with surface supplied diving .