Two BDNF Producing Activities are Better , How about Five or More?

This abstract shows that exercise and cognitive brain gaming improved cognitive function in older individuals.

I believe this verifies that exercise and cognitive training increases BDNF more than exercise alone , improving cognition/memory, mood and metabolism.  A proxy for serum BDNF level is heart rate variability which is a function of noradrenalin produced during exercise of both body and mind and its effect on Vagal neurons that promote greater heart rate variability. 

This partially answer the question, would other combinations of lifestyle changes increasing BDNF be synergistic resulting in greater improved memory, mood and metabolism and its proxy resting respiratory heart rate variability?

I think this will be proved! 

 Conjecture:  resting heart rate variability will become a measurable proxy for BDNF and prevent overtraining due to over exertion or age related intolerance in persons of all ages.

http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=10033638&fileId=S1355617715001083

Journal of the International Neuropsychological Society

Aerobic and Cognitive Exercise (ACE) Pilot Study for Older Adults: Executive Function Improves with Cognitive Challenge While Exergaming

Nicole Barcelos^a1, Nikita Shah^a1, Katherine Cohen^a1, Michael J. Hogan^a2, Eamon Mulkerrin^a3, Paul J. Arciero^a4, Brian D. Cohen^a1, Arthur F. Kramer^a5 and Cay Anderson-Hanley^a1