• Welcome to the DeeperBlue.com Forums, the largest online community dedicated to Freediving, Scuba Diving and Spearfishing. To gain full access to the DeeperBlue.com Forums you must register for a free account. As a registered member you will be able to:

    • Join over 44,280+ fellow diving enthusiasts from around the world on this forum
    • Participate in and browse from over 516,210+ posts.
    • Communicate privately with other divers from around the world.
    • Post your own photos or view from 7,441+ user submitted images.
    • All this and much more...

    You can gain access to all this absolutely free when you register for an account, so sign up today!

question for ya'll

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


New Member
Mar 12, 2005
Not to sound stupid, but what is the definition of a "contraction" when it comes to freediving? I am an aerobic athlete (military) and swim a lot. Lately I have been doing some basic training geared towards freediving and want to learn all that I can.

Thanks in advance

will the apnoe trainer, along with my workouts help me to increase the time I can hold my breath?
a breath-hold is usually divided into a comfortable part (no urge to breath, very relaxing) and the uncomfortable part (urge to breath, contractions, not very relaxing).
contractions are involuntary muscle contractions of your chest and ab muscles. contractions start when a high amount of co2 has accumulated in your body (o2 decreases). the frequency of contractions varies depending on people, some even don't get any at all. but that is rather rare. early contractions will be rather easy to hold but longer you hold your breath the quicker and more violent they will be. one thing to train here is the ability to hold a longer time of contractions which can be a bit demanding.
the intensity of your breathing will also influence greatly when you get contractions. hyperventilation will delay them but it is not a recommended technique. search here for 'hyperventilation', 'shallow water blackout' and 'bohr-effect'. there will be a lot more explanations. also search for threads discussing the risks and dangers of apnea! do this before any training in water!