Create the data set FITNESS. FITNESS contains age and sex of participants, as well as the number of times they exercise each week and their resting heart rate and aerobic power. 
data reflib.fitness;
   input age sex $ heart exer aero;
   datalines;
28  M  86  2   36.6
41  M  76  3   26.7
30  M  78  2   33.8
...more data lines...
29  M  54  3   44.8
48  F  66  2   28.9
36  F  66  2   33.2
;