Abstract
The purpose of this study was undertaken in order to compare the physical activity level of the mentally retarded children with respect to heart rate variation profiles.
Four male children diagnosed as hyperactive for reasons of excessive activity, four male children with hypoactive behaviors and four male ordinaryactive children were selected as the subjects from residential institution for the mentally retarded.
Heart rate signal was recorded continuously throughout a day by use of the telemetry method.
Average HR's expressed in percentage of rest value were 146% for the hyperactives and 147% for the ordinaryactives. In the hypoactive group, two different patterns were observed, those were one child(B) whose HR level was low and constant in almost all the situations and three children(A) whose HR was also rather low but occasionally reached high level under such condition that they were forced to move like the physical training period. Mean HR level of the hypoactives(A) and hypoactive(B) was 138% and 112%, respectively. Although the hyperactives and the ordinaryactives showed closely equal value, they had different HR distribution profile. Both very high HR and low HR were observed in the ordinaryactives but the hyperactives showed little periodic variation throughout the experimental period.
The ordinaryactives spent 7.2% of total experimental period at the HR level of 2 times the rest level and 4.2% for the hypoactives(A), but three of four hyperactives and the hypoactive(B) did not exceed this level.
During free play period, both the hypoactives(A) and the hypoactive(B) spent their time in the TV room or living room keeping low HR(122%), and the ordinaryactives played in the open air with high HR level(185%). The hyperactives were walking around everwhere he likes with somewhat higehr than mean level(155%).
To estimate the effects of these activity experiences on motor development, physical fitness tests were performed. Both the hyperactives and the hypoactives had poor motor abilities (grip sterength, back strength, vertical jump, trunk and 50 m run), those scores were in the range of -2.0 SD to -3.0 SD of intellectually normal group. Within this materials significant differences could not be found between both groups for each motor test measures.
