IL RECUPERO CARDIACO DOPO SFORZO

Duration of R R intervals between systoles was investigated in 19 young healthy subjects under basal conditions, during exercise and in the first 6 min of recovery. Variations in wave amplitude and period due to oscillating production of sinus stimuli were noted between subjects in basal conditions; variations tended to disappear at peak efforts, gradually returning during recovery. These variations were ascribed to a 'personal sinus rhythm'. It was not clear whether they reproduced the functional cycle of extrasinusal vegetative impulses, or were due to a kind of stimulus production by the sinus node. No relationship between characteristics of personal sinus rhythm and reactions to physical effort was found. (16 references).