In their second study, Rose et al., measured the energy cost of walking in 31 non-disabled children and compared them to 13 ambulatory children with spastic cerebral palsy (hemiplegia or diplegia), ages 7 to 17 years. To be eligible for the study, the subjects with cerebral palsy had to be able to walk on a treadmill with or without using the handrails. The investigators found that the relationship between heart rate and oxygen uptake at different walking speeds was linear in both the nondisabled subjects and the subjects with cerebral palsy.
In their third study, Rose et al. used the same data set as in their previous study (18 nondisabled children and 13 children with spastic cerebral palsy) to further determine if heart rate provided an accurate estimate of energy expenditure. An energy expenditure index (EEI) was calculated based on oxygen uptake and heart rate. The formula for EEI was heart rate minus resting heart rate, divided by walking speed. Values were plotted at different walking speeds. The investigators concluded that heart rate is an accurate indicator of energy expenditure in children with cerebral palsy and can be used in clinical settings to evaluate the energy cost of different locomotor activities.
The work of Rose and colleagues involving children with cerebral palsy has essentially demonstrated that there is a linear relationship between heart rate and oxygen consumption similar to what is observed in persons without disabilities. Therefore, an exercise prescription based on heart rate intensity formulas should be accurate for persons with cerebral palsy.