Most individuals are aware of the benefits to health of regular physical activity and have good intentions to exercise. Yet, 1.4 billion people worldwide are inactive, which suggests that turning intention into action can be challenging. Recent findings show that the intention-action gap could be explained by negative automatic reactions (which is a component of dual-task theory) to stimuli associated with physical activity. This gap is particularly concerning in older adults, who are more likely to spontaneously associate physical activity with fear, pain, or discomfort. To promote physical activity, the current project proposes to train older adults to suppress their automatic attraction toward sedentary stimuli and to respond positively to physical-activity stimuli. This evidence-based and low-cost intervention aims to improve physical functioning and quality of life for these population. The results will inform public-health policies and improve clinical interventions that aim to counteract a global health problem: the pandemic of physical inactivity.

Physical activity is one of the top contributors to health, reducing rates of cardiovascular disease, cancer, hypertension, diabetes, obesity, and depression. This wide spectrum of benefits is particularly important for older adults, who often suffer structural and functional deterioration in several physiological systems. Physical activity can reduce and delay the impact of this age-related deterioration in health and functional independence. Current interventions to enhance physical activity in older adults rely mainly on reflective processes by providing rational information about the health benefits of a physically active lifestyle. While these interventions successfully increase intention, their effect on actual behavior is weak. That is, most individuals are now aware of the positive effects of regular physical activity and have the intention to exercise. However, this intention is not sufficient and exercise plans are often not executed. This gap between intention and action is a challenge that health professionals need to address to counteract the pandemic of physical inactivity. Recent findings suggest that this inability to turn the intention into action is explained by negative automatic reactions to stimuli associated with physical activity. These automatic reactions could be particularly strong in older adults, who are more likely to associate physical activity with fear, pain, or discomfort. This study aims to test the effect of an intervention that targets the automatic processes underlying physical inactivity in older adults. The intervention is expected to reduce physical inactivity during the intervention and at follow-up, thereby improving physical functioning and quality of life.

Inclusion Criteria:

- 60 years of age or older and able to understand instructions in English.

Exclusion Criteria:

• Diagnosed psychiatric disorders or neurological condition (e.g., stork, Parkinson's disease, Alzheimer's disease, dementia)
• Unable to carry out the training program
• Unable to understand the protocol
• Motor deficit preventing physical activity without external help
• Physical health status preventing physical activity
• Alcohol or substance dependence.

Participants and research assistant will be blinded to the groups' allocation. The participant blinding success will be appraised by asking them to guess in what group there were at the trial termination. Besides, the research assistant blinding success will be appraised via detecting the group allocation (Experimental vs. Control) by research assistant at the end of data collection phase. The randomization will be generated on a computer and an independent coworker will carry out the randomization. The participant's identification number will be used to determine the sequence of randomization. Participants will be randomized in a 1:1 ratio between the intervention and active control condition.