“…Potential confounders of life satisfaction included age, sex, medication use, grip strength, MMSE, GDS, Walk Score, loneliness, self-rated health, and physical and social activities) [ 50 , 51 ]. Loneliness was measured using a single question from a three-item loneliness scale [ 52 ], “I feel isolated from others.” Self-rated health was measured using a single question, “In general, how would you rate your health?” with the following response options: good, rather good, poor, and very poor [ 53 ]. Physical activity was assessed at baseline by asking participants about their participation in the following activities during the past year: walking, cycling, jogging, swimming, muscle training, yoga, gymnastics, dancing, hiking, playing golf, playing grand golf, or ball exercise.…”