RESUMEN
BACKGROUND: The impact of excess weight on current and future walking endurance in nondisabled persons is unclear. This study examines the association between obesity and walking endurance among nondisabled persons both in late mid-life and early old age. METHODS: Participants in the Baltimore Longitudinal Study of Aging aged 60-79 years (n = 406) who reported no walking limitations, and completed a 400-meter walk "as quickly as possible" without lower-extremity pain, and had a follow-up assessment within 1.7-4.2 years. Adiposity was assessed by weight, body mass index (BMI), BMI category, and percent fat mass by DXA. RESULTS: Adjusting for age, sex, race, height, and physical activity, all adiposity measures were cross-sectionally associated with slower 400 meter time in both 60-69 and 70 to 79-year-olds (weight: ß = 1.0 and 1.2; BMI: ß = 2.8 and 3.6; and percent fat mass: ß = 2.0 and 2.0, respectively, all p < .001). With additional adjustment for initial 400-meter performance and follow-up time, in 60- to 69-year-olds, change in 400-meter time (positive ß indicates decline) was associated with all adiposity measures (weight: ß = 0.4; BMI: ß = 1.0; and percent fat mass: ß = 0.5; all p ≤ .05) but not in the older group (weight: ß = -0.4; BMI: ß = -1.2; and percent fat mass: ß = -0.2; all p ≥ .17). CONCLUSION: Excess weight and adiposity were associated with worse walking endurance in nondisabled persons aged 60-79 years and predicted accelerated decline in endurance in late mid-life adults. Weight management for mobility independence may be best targeted in obese persons approaching traditional retirement age.