Actividad física, capacidad funcional y envejecimientoun estudio desde una perspectiva bio-psico-social

Resumen

Aging is a multifactorial process resulting in damage of molecules, cells, and tissues, leading to a reduced efficacy of functions with different pathophysiological and psychosocial consequences. Likewise, it has been reported that the aging process is associated with an increased oxidative stress, and may have some degree of antioxidants deficiency leading to a cardiovascular comorbidity and mortality. Furthermore ageing is connected with a decrease in health-related quality of life (HRQoL) among elderly people. Physical performance has been associated with an increase in the generation of ROS. However, physical activity has demonstrated to tackle oxidative stress and therefore, different training degrees (i.e. resistance strength or aerobic exercise) could promote benefits by enhancing antioxidant capacity in the human body and improving HRQoL. Furthermore, this better oxidative status, as a consequence of a kind of physical activity, is responsible for some benefits (such as decreased arterial stiffness, improved endothelial function and metabolic and clotting setting, and reduced body weight). On the other hand, it has been studied that a high level of body mass index is related with oxidative stress. Experts acknowledge the needed to manage this ailment, and scientific evidence has demonstrated that physical exercise helps for improving health-related quality of life among elderly and reduces the oxidative damage related to chronic and cardiovascular disease. We propose that physical activity and physical function modulate the antioxidant capacity and the oxidative damage and also improve HRQoL among community-dwelling elderly people in both men and women. However, no studies have addressed the relationship between physical activity, physical function and those biomarkers included in the aging process (Q10, MDA, oxidized-LDL, protein carbonylation). Furthermore the effects of a combined strength and aerobic training in cardiovascular is not fully understood. The aims of this thesis are threefold. Firstly, we investigate the relationship between physical activity and functional capacity with oxidative damage (Lipid Peroxidation, LDL-oxidation and Protein Carbonilation), blood profile (lipoid, biochemical and muscle damage profiles) and antioxidant capacity (Q10) during the aging process in both men and women. Secondly, we studied the relationship between physical activity and functional capacity and Health-Related Quality of Life among community-dwelling elderly people in both men and women. Thirdly, we test the acute effects of resistance exercise combined with aerobic exercise on blood pressure among well-controlled elderly hypertensive women. Our sample is composed of 112 young (n=21) and elderly (n=91) from different day-centers and a Spanish university. Our sample was then stratified accordingly with gender, age (young and elderly), physical activity level (low, moderate and high accordingly with their IPAQ score) and functional capacity ¿only elderly- (those participants allocated under the 50th percentile were considered to have a low level of physical function and those in the 50th or above percentile were considered to have a high level of physical condition). Elderly participants were also classified accordingly to their body mass index (i.e. normal weight, overweight and obesity). Key results indicate that oxidative damage alongside with antioxidant capacity is modulated by the level of physical activity in both genders and among young and elderly. Furthermore, in elderly, physical function is positively related with antioxidant capacity among both men and women. Body mass index influences lipid peroxidation in men but not in women and also the level of Q10 among both genders. Lipid profile and muscle damage seems to be influence by physical function in both genders among elderly, moreover, those elderly scoring better in physical function reported also better scores in Health-Related Quality of Life. Finally, after a single-bout of resistance and aerobic capacity, the blood pressure (diastolic pressure) was decreased after 24 h among elderly women. Overall, the contents of this thesis advance knowledge on the evaluation and assessment of the aging process under the bio-psycho-social perspective and highlight the key role of physical activity and physical function (mainly strength and cardiovascular capacity) in the aging process. Furthermore, the results of this dissertation provide important practical insights on how health-related policy could tackle aging-related chronic diseases.