Rank correlation
The analysis is done on pairs, a member of one group compared to a member of the other group. For example, the fastest runner in the study is a member of four pairs: (1,5), (1,7), (1,8), and (1,9).  All four of these pairs support the hypothesis, because in each pair the runner from Group A is faster than the runner from Group B.  There are a total of 20 pairs, and 19 pairs support the hypothesis.  The only pair which does not support the hypothesis are the two runners with ranks 5 and 6, because in this pair, the runner from Group B had the faster time.  By the Kerby simple difference formula, 95% of the data support the hypothesis (19 of 20 pairs), and 5% do not support (1 of 20 pairs), so the rank correlation is r = .95 - .05 = .90.