I made measurements of oxygen consumption (VO2) during steady state running with 3 different shoes. The runs were performed in 5 series of 3 runs, where each of the 3 successive runs was performed with different shoes. From the results of VO2 it is seen that the place of the runs within a series has an important impact. Can I do any statistics if I have at least one sample of each combination (each shoe was used at least once in the first run of a series, in the second and the third run of a series)?

So I have two effects (shoe and place of the run), but for each combination of effects there is 1 to 3 samples.

Any help is appreciated. Thank you very much.

Jurij