Physical activity and amyloid beta in middle-aged and older adults: A systematic review and meta-analysis oleh María Rodriguez-Ayllon, Patricio Solis-Urra, Cristina Arroyo-Ávila, Miriam Álvarez-Ortega, Pablo Molina-García, Cristina Molina-Hidalgo, Manuel Gómez-Río, Belinda Brown, Kirk I. Erickson, Irene Esteban-Cornejo