To BradMM
Next month 77 for me !
Last time in a quarry it was in september 2016 ( at 20m)
A small film I’ve done at La Gombe in Belgium 11/10/2015
https://vimeo.com/142274793
After Indonesia I wasn't anymore attracted by cold and dark Water…of the quarries.
Another film I've done in Indonesia Kri n°1 2017 =>
And the last example in Red sea 2018 chapter 5 (Zerib Kebir) =>
Before the small trip to the cave, I had descended to 21 m with my video camera fixed on a large wing ... It's not so easy that in "snorkeling" state along the vertical rope and hands free.
I must say that I lost all the training (AIDA) in pool at the beginning of the year ... because of a pulmonary infection.
I was tired and unwilling to participate in AIDA training that starts at 21h! But I hope to find better conditions to participate again in training.
In Belgium, divers and freedivers are obliged to perform an exercise test every year (from the age of 50) in a cardiologist's home.
Up to now my heart is very good…( I'm member of race bike club .)
Last year I climbed "by pushing on the pedal of my bike" ;-) the famous Mont Ventoux.
=>
Mont Ventoux - Wikipedia
So if your physical condition is Ok (and you seems to be in a very good healthy) No problem to practice « Freediving ».
BUT ... after visiting your cardiologist ... and after taking a basic "freediving course", you need to know the safety rules to avoid accidents….No hyper ventilation.
To Akimo
You followed The PFI...

It's written "« Learn to freedive down to a maximum depth of 40m/132 feet! »
Did you dive down to 40m?
If yes : in which discipline (Constant Weight - CW) , (Free Immersion - FI) or (No Limit) ?