1 Centre de Recherche, Institut Universitaire de Gériatrie de Montréal, Montréal, QC, Canada.
2 Département de Psychologie, Université du Québec à Montréal, Montréal, QC, Canada.
3 Centre de Recherche, Institut de Cardiologie de Montréal, Montréal, QC, Canada.
4 Département des Sciences de l'Activité Physique, Université du Québec à Montréal, Montréal, QC, Canada.
5 Département de Médecine, Université de Montréal, Montréal, QC, Canada.
6 Département de Médecine, Centre Hospitalier de l'Université de Montréal, Service de Gériatrie, Montréal, QC, Canada.
7 PERFORM Centre, Concordia University, Montréal, QC, Canada.

Associations between cardiorespiratory fitness and brain health in healthy older adults have been reported using a variety of cardiorespiratory fitness estimates (CRFe). Using commonly used methods to determine CRF, we assessed the relationship between CRFe and executive function performance. Healthy older adults (n = 60, mean age 68 years, 77% women), underwent three CRF tests: a Maximal Graded Exercise Test performed on a cycle ergometer, the Rockport Fitness Walking Test, and a Non-Exercise Prediction Equation. Executive function was assessed by a computerized cognitive assessment using an N-Back task (updating cost) and a Stroop task (interference cost, global and local switch cost). Multiple hierarchical regression analyses were conducted to assess the relationship between different CRFe and executive function performance. Regardless of age and education, cardiorespiratory fitness estimated from the Maximal Graded Exercise Test and the Rockport Fitness Walking Test was significantly associated with the global switch cost. All CRFe were associated with the interference cost. No association was observed between CRFe and local switching costs or the updating costs. In the present study, not all subcomponents of executive function were related to CRFe. Interestingly, the executive functions that were associated with CRFe are those that are known to be the most affected by aging.