Energetic Cost of Walking and Brain Atrophy in Mid-to-Late Life

Abstract

Background Higher energetic costs for mobility are associated with declining gait speed and slow gait is linked to cognitive decline and Alzheimer’s disease. However, the physiological underpinnings of gait and brain health have not been well explored. We examined the associations of the energetic cost of walking with brain volume in cognitively unimpaired adults from the Baltimore Longitudinal Study of Aging. Methods We used brain MRI data from 850 participants (mean baseline age 66.3±14.5 years), of whom 451 had longitudinal MRI data (2.8±1.0 MRI scans over 4.0±2.0 years). The energetic cost of walking was assessed as the average energy expended (V̇O2) during 2.5 minutes of customary-paced overground walking. Multivariable linear mixed effects models examined the associations between baseline energetic cost of walking and regional brain volumes adjusting for covariates. Results At baseline, higher energetic cost of walking was cross-sectionally associated with lower gray and white matter volumes within the frontal, parietal, and temporal lobes, as well as hippocampal, total brain, and larger ventricular volumes (all FDR p< 0.05). A baseline energetic cost of walking × time interaction demonstrated that participants with higher energetic cost of walking had faster annual decline in hippocampal volume (FDR p= 0.01) and accelerated annual increase in ventricular volumes (FDR p= 0.01). Conclusions The energetic cost of walking is associated with gray and white matter volumes and subsequent hippocampal atrophy and ventricular enlargement. Collectively, these data suggest the energetic cost of walking may be an early marker of neurodegeneration that contributes to the gait brain connection.

Walking energetics and white matter hyperintensities in mid‐to‐late adulthood

“…In the present study we found that adults with lower slow‐paced walking V̇O 2 (i.e., more efficient energy use) had less WMHs. This finding complements our recent research that found a lower energetic cost of walking was associated with less Aβ deposition, a defining pathophysiologic feature of AD, and an attenuated rate of brain atrophy within regions that are vulnerable to age‐ and AD‐related neurodegeneration 27,28 . This study also observed that peak‐paced walking V̇O 2 , an estimate of aerobic capacity, was negatively associated with WMHs.…”

“…This finding complements our recent research that found a lower energetic cost of walking was associated with less Aβ deposition, a defining pathophysiologic feature of AD, and an attenuated rate of brain atrophy within regions that are vulnerable to age-and AD-related neurodegeneration. 27,28 This study also observed that peak-paced walking V Ȯ2 , an estimate of aerobic capacity, was negatively associated with WMHs. This is in agreement with previous studies showing older adults with higher aerobic capacity tend to have lower WMH burden 48,49 (but see also Burzynska et al 50 ).…”

“…[24][25][26] More recent evidence suggests these measures of walking energetics are also associated with AD-related pathology (amyloid beta [Aβ] deposition), white and gray matter brain volume, and cognitive performance in cognitively unimpaired midto late-aged adults. [27][28][29][30][31][32] Collectively, these findings suggest that the energy costs for mobility may reflect underlying changes that precede adverse changes in cognitive and motor function. Moreover, given that cerebral vascular dysfunction likely contributes to age-and disease-related pathology (e.g., brain atrophy, Aβ), it may underlie the previously observed walking energetics-brain associations.…”

“…Previous research has demonstrated that the energy costs for mobility, measured through oxygen consumption (V̇O 2 ), worsen in older age and predict mobility decline 24–26 . More recent evidence suggests these measures of walking energetics are also associated with AD‐related pathology (amyloid beta [Aβ] deposition), white and gray matter brain volume, and cognitive performance in cognitively unimpaired mid‐ to late‐aged adults 27–32 . Collectively, these findings suggest that the energy costs for mobility may reflect underlying changes that precede adverse changes in cognitive and motor function.…”

Comparação do desempenho funcional e parâmetros cinemáticos da marcha em idosos com fragilidade e saudáveis

“…Em seguida, os idosos foram submetidos à identificação da condição da mobilidade pelo Short Physical Performance Battery (SPPB), avaliação do nível de atividade física por meio do Minnessota Leisure Activity Time Questionnaire. Foi realizada também a avaliação da tolerância do idoso ao exercício e a saturação de O2 durante um exercício submáximo, através do teste de caminhada de 400 metros (TC400m), que fornece uma estimativa válida do consumo máximo de oxigênio (VO2máx) do idoso, estando associado à capacidade física e aeróbica do idoso 13,14 .…”