Just browsed through the Abstract. Some unrelated thoughts: I think the issue that most people won't gather up the will to do aerobic exercise after they are mentally exhausted -- even that they know it works to some extent. Following this, I believe, without scientific proof, that genius (or others who can contribute significantly more than other people) have their mind wired completely different from other people.…
https://ecosophia.dreamwidth.org/tag/will
I suppose it might be a question of whether having enough willpower to start the exercises disqualifies one from being 'weak minded'