> The authors' claims about BDNF are supported by a p-value of p = .046, and having main conclusions hinge on p-values of p > .01 usually means the conclusions are rubbish.

Also, I don't have the references handy, but I recall other studies showing that exercise-induced BDNF changes can be mediated by e.g. air pollution. So even if the difference there is real, it might be premature to attribute it specifically to the mode of training.