exercise...
Yes.
by doing activities and being scared or screaming
During periods of high emotion, the sympathetic nervous system is activated, leading to the release of stress hormones such as adrenaline. This triggers an increase in heart rate and respiration to prepare the body for "fight or flight" response. This physiological response is meant to provide the body with the energy needed to cope with the stressful situation.
the best exercise is either cardio or running
too little oxygen
Blackish and burnt. :(
parasympathetic
The noun 'laughter' is an uncountable noun. Units of laughter are expressed in amounts such as some laughter, a lot of laughter, much laughter, etc.
Parasympathetic. (Apex)
incrasing metabolism increasing pump cardiac muscle to pump the blood circulation
Laughter.