Year of Award

2007

Document Type

Dissertation

Degree Type

Doctor of Philosophy (PhD)

Degree Name

Interdisciplinary Studies

Department or School/College

Interdisciplinary Studies Program

Committee Chair

Steven Fehrer

Commitee Members

Steven Gaskill, James Laskin, Lawrence Dent, Daniel Dennis, John Lundt

Keywords

Epidemiology, Health Sciences, Public Health, Rehabilitation and Therapy

Abstract

Cardiovascular disease (CVD) accounts for 37.1 percent of all deaths in the United States. Physical activity is inversely related to both CV event risk and to many of the individual CVD risk factors. The inverse relationship between physical activity and CVD risk is well established. However, much dispute remains about the optimal physical activity intensity and duration related to health benefits and to lower CVD risk. The ability to objectively measure intensity and duration may clarify the inverse relationship between physical activity and CVD. The purpose of this collection of studies was to explore the association of physical activity with CVD and attempt to identify some specifics of this complex relationship. Results: In healthy sedentary individuals aged 31 to 66, 2 different activity accumulation programs were effective in increasing physical activity and resulted in improved fitness and blood glucose. However, the improvement in activity was not of sufficient intensity to provide changes in multiple heart disease risk factors or inflammation. In a cross-section sample of males and females aged 18 to 65, both active and sedentary, the relationship between physical activity and CVD risk varied by age group. The inverse relationship between physical activity and CVD risk was confirmed. However, reaching higher intensity levels for 1 minute periods at least 5 minutes a day appears to be better related to lower risk of CVD than longer durations of moderate or vigorous activity per day, particularly in younger individuals. In a sample of stroke survivors aged 50 to 72, 3 out of 6 of the modifiable risk factors for CVD were present. In these stroke survivors, physical activity intensity and duration were well below current recommendations and insufficient for CVD risk reduction. Conclusions: Accumulating activity can be effective in meeting physical activity recommendations however both duration and intensity requirements must be achieved. Combinations of higher intensities for shorter durations may also be effective in CVD risk reduction.

Download

Share

COinS
 

© Copyright 2007 Coral Michelle Gubler