The regression sum of squares, R(β_1 β_3 β_2 β_4| β_0) is used to test the
composite hypothesis H_0: β_1 = β_3 = β_2 = β_4 = 0. This gives F = 22.16
which, with 4 and 26 degrees of freedom is highly significant. That is, there
is evidence to believe that the independent variables need to be included
in the model to account for the variability in oxygen consumption among
runners.