Electrocardiograms (EKGs) were collected by researchers blind to the infant's
group assignment for a total of 30 min (10 min baseline, 10 min treatment,
and 10 min post-treatment). Inasmuch as only short term, heart
rate variability changes have been observed following tactile–kinesthetic
stimulation [8], EKGs were collected to assess short term changes in
heart rate variability on the morning of the third day of the study, as
this marked the midpoint of the study treatment protocol. All infants
continued to receive standard nursery care during the course of the
study.