Aerobic exercise training effects on hippocampal volume in healthy older individuals: a meta-analysis of randomized controlled trials.

We conducted a meta-analysis of randomized controlled trials investigating the effects of aerobic exercise training (AET) lasting ≥ 4 weeks on hippocampal volume and cardiorespiratory fitness (CRF) in cognitively unimpaired, healthy older individuals. Random-effects robust variance estimation models were used to test differences between AET and controls, while meta-regressions tested associations between CRF and hippocampal volume changes. We included eight studies (N = 554) delivering fully supervised AET for 3 to 12 months (M = 7.8, SD = 4.5) with an average AET volume of 129.85 min/week (SD = 45.5) at moderate-to-vigorous intensity. There were no significant effects of AET on hippocampal volume (SMD = 0.10, 95% CI - 0.01 to 0.21, p = 0.073), but AET moderately improved CRF (SMD = 0.30, 95% CI 0.12 to 0.48, p = 0.005). Improvement in CRF was not associated with changes in hippocampal volume (bSE = 0.05, SE = 0.51, p = 0.923). From the limited number of studies, AET does not seem to impact hippocampal volume in cognitively unimpaired, healthy older individuals. Notable methodological limitations across investigations might mask the lack of effects.

An examination of the validity of neuropsychological and physical testing batteries in Latin-American adults aged over 55 years.

BACKGROUND: Valid and reliable measurements are necessary to understand and monitor age-related changes. AIMS: To describe the factor structure and provide validity evidence of a neuropsychological and a physical testing batteries using factor analysis. METHODS: We performed a secondary analysis of data from the Epidemiology and Development of Alzheimer's Disease (EDAD) project. Community-dwelling adults aged 55 to 85 years underwent comprehensive physical and neuropsychological assessments. An exploratory factor analysis was performed on both assessment batteries. The models were later confirmed with a random subsample using confirmatory factor analysis. RESULTS: Data from 238 adults (163 females and 75 males) was included. The neuropsychological model revealed a four-factor structure formed by "Executive Functioning", "Verbal Memory", "Logical Memory", and "Labeling And Reading" (Extraction Sums of Squared Loadings [ESSL] = 56.41% explained variance; Standardized Root Mean Square Residual [SRMSR] = 0.06; Comparative Fit Index [CFI] = 0.98). The physical model was formed by a two-factor structure including "Health-related Fitness and "Functional Fitness" (ESSL = 50.54% explained variance; SRMSR = 0.07; CFI = 0.93). DISCUSSION: To our knowledge, this is the first study to analyze the structure of comprehensive testing batteries for the Latin-American older adults. Our analysis contributes to the understanding of theoretical constructs that are evaluated in the EDAD project. CONCLUSION: Our findings provide validity evidence for simplified and reduced testing batteries, which imply shorter testing times and fewer resources.

Predicting Exertion from Metabolic, Physiological and Cognitive Variables in Older Adults / Predicción del esfuerzo con variables metabólicas, fisiológicas y cognitivas en adultos mayores / Predição do esforço com variáveis metabólicas, fisiológicas e congênitas em idosos

Abstract Objective. To determine the association between perceived exertion (RPE) and physiological variables and to determine the predictive factors of RPE during submaximal and maximal exertion in older adults. Method. Older adults from Kansas (n = 100) and Costa Rica (n = 79) performed a submaximal and maximal stress test. RPE, education level and a total score of cognitive function (CFTS) were collected. Correlation and multiple regression analyses were computed using RPE as the criterion variable and oxygen consumption (VO2), respiratory exchange ratio (RER), CFTS and education level as predictors. Results. There was a significant correlation between VEP and RER (r = 0.22, p = 0.029) at maximal exertion. The RPE predictors for women were VO2, RER, and CFTS at different stages of the test. For men, VEP was predicted by RER, education level, and VO2 at different stages. Conclusion. Metabolic and physiological variables predicted RPE in older adults. Age, cognition, and heart rate were unrelated to RPE at maximal exertion, and RER predicted RPE scores during submaximal and maximal exertion.

Resumen Objetivo. Determinar la asociación entre el esfuerzo percibido (VEP) y variables fisiológicas y determinar los factores predictivos de VEP durante el esfuerzo submáximo y máximo en adultos mayores. Método. Adultos mayores de Kansas (n = 100) y Costa Rica (n = 79) realizaron una prueba de esfuerzo submáxima y máxima. Se recopiló la VEP, nivel de educación y una puntuación total de la función cognitiva (PTFC). Se usaron análisis de correlación y regresión múltiple utilizando VEP como variable criterio y el consumo de oxígeno (VO2), tasa de intercambio respiratorio (RER), PTFC y nivel de educación como predictores. Resultados. Se encontró una correlación significativa entre la VEP y la RER (r = 0.22, p = 0.029) en el esfuerzo máximo. Los predictores de VEP para las mujeres fueron VO2, RER y PTFC en diferentes etapas de la prueba. Para los hombres, la VEP fue predicha por RER, nivel de educación y VO2 en diferentes etapas. Conclusión. Las variables metabólicas y fisiológicas predijeron los valores de VEP en adultos mayores. La edad, la cognición y la FC no se relacionaron con la VEP en el esfuerzo máximo y la RER predijo las puntuaciones de la VEP durante el esfuerzo submáximo y máximo.

Resumo Escopo. Determinar a associação entre o esforço percebido (VEP) e as variáveis fisiológicas e determinar os fatores preditivos de VEP durante o esforço submáximo e máximo em idosos. Metodologia. Idosos de Kansas (n= 100) e Costa Rica (n= 79) realizaram uma prova de esforço submáxima e máxima. Foi recopilada o VEP, nível de educação e pontuação total da função cognitiva (PTFCO. Foram usadas análises de correlação e regressão múltipla utilizando VEP como variável critério e o consumo de oxigeno (VO2), taxa de intercambio respiratório (RER), PTFC e nível de educação como preditores. Resultados. Foi encontrada uma correlação significativa entre a VEP e a RER (r = 0.22, p = 0.029)) no esforço máximo. Os preditores de VEP para as mulheres foram VO2, RER e PTFC em diferentes etapas da prova. Para os homens, a VEP foi predita por RER, nível de educação e VO2 em diferentes etapas. Conclusão. As variáveis metabólicas e fisiológicas predisseram os valores de VEP em idosos. A idade, a cognição e a FC não estiveram relacionadas com a VEP no esforço máximo e a RER predizia as pontuações da VEP durante o esforço submáximo e máximo.