Normaly the body has to be really pure to have a slow heart beat and slow breath.
The professional runners normally have a slow beat.
The ill person with allot of accumulations is struggling to survive and the heart is very over worked as is the nervous system that actually creates the pressure that the heart just regulates.
Some well educated people who mostly live on air only, may take a breath of air every few minutes and also be able to hold their breath for 1/2 hour or more.
Again, the ill person can't hold their breath more than 1 minute or they will suffer in thier own waste.