In the present study the effects of a ten-week physical training program on physical efficiency, work capacity and classroom-attention of 11 motorically handicapped children (between 8 and 14 years old) were examined. A physical training program for the children in the experimental group (n = 6) consisted of an intensification of the activities (assessed by means of heart rate recordings) of the scheduled physical education lessons, while the control group (n = 5) followed the same lessons without the intensity of the activities being changed. During all the lessons, the experimental group was required to achieve a minimum heart rate value of 160 beats X min-1. Physical efficiency and physical work capacity scores were calculated from the obtained relationships of respectively oxygen uptake versus workload and of oxygen uptake versus heart rate, determined during a submaximal bicycle ergometer test. Attention in the classroom was measured by means of a previously developed observation instrument. At the end of the ten-week training program a significant increase in physical efficiency and classroom-attention scores was demonstrated for the children in the experimental group. Such effects could not be demonstrated for the children in the control group. The implication that can be drawn from this finding is that the motorically handicapped children in the experimental group after having received special physical training can perform the same amount of external work with less energy expenditure. Further, their attention behaviour in the classroom situation appears to be facilitated. A follow-up study, carried out some months after the end of the training program, showed for both groups a deterioration in physical efficiency scores, while the experimental group also deteriotated in terms of their attention scores. It is suggested that an intensification of activities during the scheduled physical education lesson can have positive effects both physical and psychological on motorically handicapped children.