Photo: Dan Bolt
In this category the freediver descends along a vertical line using a pair of bi-fins or a monofin. The freediver can only use the line for guidance and can pull it once at the target depth. The key point is that the diver is not allowed to change his ballast during the dive. Until the last few years, carbon fibre fins were the most common fins used by top freedivers. However, monofins have gained increasing popularity and have been shown to be more efficient means of propulsion.
In short: Swimming down and back up
Manual Of Freediving:
Underwater On A Single Breath
Freediving is a potentially dangerous activity. This website exists only to provide general information about freediving and does not constitute any form of instruction. Individuals interested in freediving are strongly encouraged to undertake a course with a qualified instructor and to never freedive alone. The BFA accepts no liability for injury or death resulting from the use of information on this website.