It was thought that a special program can help improve the blood pressure of heart patients. seven subjects participated in a study to test this contention. Before the program started, the working capacity of each person was determined by measuring the time it took to reach a heart rate of 110 beats per minute while biking; investigators believed that controlled exercise would benefit a patient if the time it took could be increased. After 20 weeks of controlled exercise, the biking measurements were repeated and the following data were obtained:

Pretest 3, 6.5, 2.2, 1.7, 1.7, 9.0, 3

Posttest 5.5, 4.5, 8, 4.3, 9.8, 1.4, 3

Does this data follow the beliefs of the investigators.