Background: Participation in physical activity is recommended for children with cerebral palsy (CP). When performing physical exercise, reactivity of the cardiac autonomic nervous system is needed. It was found that children with CP have poor cardiac autonomic function during rest and passive posture change.
Aim: The aim of this study was to describe the function of the cardiac autonomic system of three children with CP, classified at different levels according to the Gross Motor Function Classification System (GMFCS). Cardiac autonomic system functioning was assessed during a sub maximal treadmill test and during the recovery immediately following the test, using various indices of heart rate (HR) and heart rate variability (HRV).
Method: Participants included three children, 9-, 10- and 12 years-old, with cerebral palsy classified at GMFCS levels I, II, and III, respectively. Heart rate monitoring was carried out in three modes; at rest, while performing a sub-maximal treadmill test according to the Modified Naughton protocol, and the during recovery phase immediately following the test. Heart rate was monitored using a Polar watch RC800CX and transmitter. The data were transferred to software, and heart rate indices were calculated for each of the three modes; rest, treadmill test, and recovery.
Results: An inverse relationship was found between the duration of the treadmill test and the mobility level. We noticed HR response in all three children to the treadmill test and at rest posttest. The values of HR and various indices were the most outstanding for the highest functioning child - GMFCS I. None of the three children returned to resting HR rates during the post-test recovery time.
The three children discussed in this case report showed cardiac autonomic response to a treadmill test. The response was associated with the motor mobility function.
Keywords: cerebral palsy, heart rate, heart rate variability, GMFCS, sub-maximal effort.