One of the main causes of death in the European Union (EU) is cardiovascular disease (CVD) which accounts for more than two million deaths every year. This equates to almost all half (42%) of all deaths within the region (Rayner et al. 2009). Although there are many contributing factors to CVD, inactivity has been shown to be one of the major risk factors (Howard et al. 2008; Owens et al. 2010). Arterial stiffness has also been shown to be an important CVD risk factor (Laurent et al. 2006) and, when measured via pulse wave velocity (PWV), has been shown to be a strong independent predictor of cardiovascular morbidity (Noor et al. 2009). To date there has been limited research investigating the effects of moderate activity on arterial stiffness, therefore, the aim of this thesis was to investigate the effects of brisk walking on CVD risk factors in overweight individuals, with particular reference to arterial stiffness. There were two studies carried out within the parameters of this thesis. An acute study (n17) investigated the effects of a single 30 minute walk on CVD risk factors. This was followed by a longer 6 month intervention (n77), investigating the effects of accumulated brisk walking (3 x 10 minutes) on the same risk factors. In the acute study, there were no significant changes (p > 0.05) to the CVD markers (blood pressure, PWV, lipid profiles, fasting glucose or fasting insulin.) It was concluded that a higher walking intensity may be required to elicit significant changes. The same set of CVD makers were measured in the 6 month walking study and although there were no significant changes to blood pressure, lipid profiles, fasting glucose or fasting insulin, the accumulated brisk walking did result in a significant decrease in arterial stiffness (p < 0.05). This decrease was maintained up to four months post intervention. NOx (a surrogate 'marker for the vasodilator Nitric oxide) was measured as possible mechanism for this decrease in PWV, with the result pointing to a possible relationship as a strong negative correlation between the two variables was found (r = -0.65, P < 0.001). Over the last number of years there has been much research which clearly proves that an active lifestyle is a major factor in achieving good health, and that a sedentary lifestyle is associated with ill health and a shorter life expectancy (Blair et al. 2004). The research within this thesis enhances the existing body of knowledge on the effects of walking on CVD risk factors, as it can be concluded that brisk walking can successfully reduce arterial stiffness in overweight individuals even without changes in other risk factors.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:587496 |
Date | January 2011 |
Creators | Kearney, Thérèse |
Publisher | University of Ulster |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
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