Acute effects of endurance exercise on breath hold diving

[SDS]

Hi all,

I am wondering about your personal experiences about the acute (not long-term) effects of endurance exercise on freedive performance.

Yesterday, I went for a bike ride (~86 km) 2-3 h prior to a dive session. I am new to freediving, and before yesterday, I had not gone deeper than ~25 m (mostly due to equalisation restrictions). However, yesterday I repeatedly went beyond 25 m, up to 33 m at the end of the session.

Initially I expected diving performance to be negatively affected by excess post-exercise oxygen consumption (EPOC). Though I have to say that once in the water I felt relax and calm, not that tired from the previous ride.
On the other hand, regular exercise in athletes is known to impair chemoresponsiveness, reducing the urge to breathe at increasing PaCO2 and decreasing Pa02 (i.e., resulting in exercise-induced hypoxemia at sea level and low hypoxic ventilatory response in hypoxia at altitude).
In my case, prior exercise might have just facilitated equalisation during diving and therefore addressed the primary barrier for me at that time. I have previously noticed a positive effect of acute exercise on the ease with which I can open the eustachian tube (though not sure the effect would last more than 3 hours).

Anyhow, curious to hear about your experiences!

Best,
Stefan

 

[psimian]

My best guess is that this comes down to hormone levels and the relative sympathetic/parasympathetic nervous system activation levels. As long as the endurance exercise is not intense enough to trigger a full blown fight-or-flight response from the sympathetic nervous system, I would expect it to have a positive effect on freediving.

I find the best pre-dive exercise to be something that is mentally and physically easy, but of long enough duration for you to really get into a groove. This way you burn off all of the adrenaline and get your mind into a relaxed state before you introduce the stress of diving. For me, it takes upwards of 45 minutes of easy exercise before I can really relax and clear my mind. If I push too hard during the warmup (for example, doing a couple of maximal sprints as part of the warmup) I have a lot of trouble relaxing even if my body is physically ready for diving. This makes sense, since intense exercise activates the sympathetic nervous system (high energy, elevated heart rate, etc.), and the effects can last for hours. Activities like meditation and gentle exercise increase the parasympathetic system activation (rest, digestion, recovery, etc.) which is more favorable to freediving.

I would suggest trying a long, easy ride (<50% Max HR, 1 hour duration) before diving, and see if you get the same results.

 

[J Campbell]

My pool dive practice is better if I swim laps for 20 or 30 mins beforehand.