Detalhes bibliográficos
| Ano de defesa: |
2016 |
| Autor(a) principal: |
Sales, Marcelo Pereira Magalh??es de
 |
| Orientador(a): |
Sim??es, Herbert Gustavo
|
| Banca de defesa: |
Não Informado pela instituição |
| Tipo de documento: |
Tese
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Cat??lica de Bras??lia
|
| Programa de Pós-Graduação: |
Programa Strictu Sensu em Educa????o F??sica
|
| Departamento: |
Escola de Sa??de e Medicina
|
| País: |
Brasil
|
| Palavras-chave em Português: |
|
| Área do conhecimento CNPq: |
|
| Resumo em Inglês: |
Diabetes is associated with endothelial dysfunction and several cardiovascular disorders, such as systemic arterial hypertension. Moreover, hypertension and diabetes coexist very frequently, as 60-65% of diabetics are hypertensive. The coexistence of hypertension and diabetes can reduce endothelium-mediated vasodilatation, which can be partially explained by a reduced production of nitric oxide (NO) or a decreased response to NO in the vascular smooth muscle. On the other hand, it has been shown that a single session of exercise can promote significant reductions in blood pressure (BP). This occurrence is known as post-exercise hypotension (PEH) and appears to be associated with the activity of the kallikrein-kinin system and release of NO. Although studies have observed PEH in individuais with T2D the molecular mechanisms have not been fully elucidated. ln addition, the prescription of exercise intensities based on lactate threshold (L T) has been suggested for individuais with T2D.Moreover, in spite of previous studies showing that individuais with T2D exhibit PEH when exercising at intensities around LT , There is evidence that subjects with T2D exhibit lower plasma kallikrein activity (PKA) compared to healthy individuais, suggesting that lower NO release and reduced endothelium-dependent vasodilation would be occurring in response to exercise for this population. However, no investigations were made on the integrated responses of PKA, BK, dessArg9-BK and NO and its association to the occurrence of PEH in individuais with or without T2D.Furthermore, to the best of our Knowledge, there is only one study that has investigated the effects of exercise (aerobic and / or resistance) on the 24-hour BP response in individuais with T2D. Not to mention that it is not of our knowledge, studies that have investigated the effects of different aerobic exercise intesities on BP 24 hours in subjects with T2D.Additionally, Several studies have investigated the effects of different exercise modes ( e.g., aerobic vs. resistance ), intensities, and durations on BP responses during the post-exercise recovery period. Studies regarding the effects of different sports modalities, especially martial arts, have also been performed, such as: Tai Chi Chuan, Jiu Jitsu, and Judo. However, until now, no study has explored the BP responses after a single Contact Karate (CK) session. It is worth mentioning that the scientific literature related to combat sports has hardly been explored, especially regarding health-related variables (i.e., post-exercise BP reduction). Most studies have investigated performance-related parameters in athletes, making the evaluation of health-related variables (such as PEH) a scientific gap. Therefore, investigations related to this issue have been strongly encouraged. It should be noted that given the known complications of type 2 diabetes and characteristics of sport (high physical contact of high impact), it is wise to initially investigate the effects of a contact karate session on the blood pressure response after exercise in apparently healthy subjects and then, if possible, in special populations as diabetes and hypertension. With regard to chronic exercise, in particular the resistance exercise, the available literature concerning their effects on the response of NO and, in tum, on BP in individuais with T2D, it is still incipient. To the best of our knowledge, there have been only two randomized clinical trials ofRT's effects on NO concentration and BP levels in T2D patients, only one of which, verified the NO response (along with BP) due to R T. Therefore, there is an apparent lack of evidence on R T' s effects on the responses of NO and BP in T2D patients. Objectives: Study 1) to investigate and compare the responses of PKA, BK, desArg9-BK, NO and BP after a single session of moderate-intensity aerobic exercise in T2D and non-diabetic (ND) individuais; study 2) To verify the effects of different intensities of aerobic exercise on 24-hour ambulatory BP responses in individuais with T2D and prehypertension; study 3) to verify the effects of a Contact Karate (CK) session on BP responses during a post-exercise recovery period in young adults; study 4) to determine the effects of eight weeks RT on the responses of NO and BP in T2D patients and their controls peers. Methods: study l)Ten subjects with T2D and 10 Non-diabetics (ND) underwent three sessions: 1) maximal incremental test on cycle ergometer to determine lactate threshold (L T); 2) 20- min of constant-load exercise on cycle ergometer, at 90% LT and; 3) control session. BP and oxygen uptake were measured at rest and at 15, 30 and 45 min post-exercise. Venous blood samples were collected at 15 and 45 minutes of the recovery period for further analysis of PKA, BK and desArg9-BK. NO was analyzed at 15 minutes post exercise. Study 2) ten individuals with T2D and prehypertension completed three sessions applied in random order: non-exercise control (CON) and exercise at moderate (MOD) and maximal (MAX) intensities. Heart rate (HR), BP, blood lactate concentrations ([Lac ]), oxygen uptake (VO2), and rate of perceived exertion (RPE) were measured at rest, during the experimental sessions, and during the 60 min recovery period. After this period, ambulatory blood pressure was monitored for 24 h. Study 2) ten individuals with T2D and prehypertension completed three sessions applied in random order: non-exercise control (CON) and exercise at moderate (MOD) and maximal (MAX) intensities. Heart rate (HR), BP, blood lactate concentrations ([Lac ]), oxygen uptake (VO2), and rate of perceived exertion (RPE) were measured at rest, during the experimental sessions, and during the 60 min recovery period. After this period, ambulatory blood pressure was monitored for 24 h. Study 3) Thirty-two male CK athletes volunteered and underwent one CK session (50 min) anda control session. BP was measured during rest (before sessions), as well as on the 15th, 30th, 45th, and 60th min of the post-exercise recovery. Study 4) We performed eight-weeks of randomized controlled trial in T2D patients and ND individuals. After initial screening, were randomly allocated into four groups: (1) trained T2D (T2DTRAINED; n = 9), (2) trained ND (NDTRAINED; n = 10), (3) control T2D (T2DCON; n = 8) and (4) control ND (NDCON; n = 7). NO and BP were determined before and after the intervention. Results: study 1) The ND group presented PEH of systolic blood pressure (SBP) and mean arterial pressure (MAP) on the 90% L T session but T2D group did not. Plasma NO increased ~24.4% for ND and ~13.8% for T2D group 15min after the exercise session. Additionally, only ND individuais showed increases in PKA and BK in response to exercise and only T2D group showed increased desArg9-BK production. Study 2) Compared with CON, only MAX elicited post-exercise BP reduction that lasted for 8 h after exercise and during sleep. Study 3) The SBP, diastolic blood pressure, and MAP were significantly lower at the post-exercise period compared to pre-exercise rest (p<.05), with the largest reductions being observed at the 60th min of recovery and at the sarne periods of post-exercise recovery of the control session. Study 4) After eight weeks of RT (three times per week), the T2D and ND experimental groups decreased systolic blood pressure (SBP) by 7.0 and 3.4 mmHg, respectively. However, the control groups showed maintenance (0.24 mmHg for T2D) or elevation (2.2 mmHg for ND) of systolic blood pressure. Although none of these changes were significant (p > .05). As regards the absolute values of BP, T2D subjects who did not undergo the training (T2DCON) tended (p = .057) to have increase SBP and significantly (p = .05) increased MAP. Conclusions: studyl) it was concluded that T2D individuals presented lower PKA, BK and NOx release as well as higher desArg9-BK production and reduced PEH in relation to ND participants after a single exercise session. Study 2) A single session of aerobic exercise resulted in 24 h BP reductions in individuals with T2D, especially while sleeping, and this reduction seems to be dependent on the intensity of the exercise performed. Study 3) a single CK session can promote a decrease in BP for at least 60 min after performing this type of exercise in young adults. Study 4) eight weeks of RT does not increase NO concentrations and, in tum, does not reduce BP in T2D patients-though it prevented its increase. |
| Link de acesso: |
https://bdtd.ucb.br:8443/jspui/handle/tede/2076
|
Resumo: |
Diabetes is associated with endothelial dysfunction and several cardiovascular disorders, such as systemic arterial hypertension. Moreover, hypertension and diabetes coexist very frequently, as 60-65% of diabetics are hypertensive. The coexistence of hypertension and diabetes can reduce endothelium-mediated vasodilatation, which can be partially explained by a reduced production of nitric oxide (NO) or a decreased response to NO in the vascular smooth muscle. On the other hand, it has been shown that a single session of exercise can promote significant reductions in blood pressure (BP). This occurrence is known as post-exercise hypotension (PEH) and appears to be associated with the activity of the kallikrein-kinin system and release of NO. Although studies have observed PEH in individuais with T2D the molecular mechanisms have not been fully elucidated. ln addition, the prescription of exercise intensities based on lactate threshold (L T) has been suggested for individuais with T2D.Moreover, in spite of previous studies showing that individuais with T2D exhibit PEH when exercising at intensities around LT , There is evidence that subjects with T2D exhibit lower plasma kallikrein activity (PKA) compared to healthy individuais, suggesting that lower NO release and reduced endothelium-dependent vasodilation would be occurring in response to exercise for this population. However, no investigations were made on the integrated responses of PKA, BK, dessArg9-BK and NO and its association to the occurrence of PEH in individuais with or without T2D.Furthermore, to the best of our Knowledge, there is only one study that has investigated the effects of exercise (aerobic and / or resistance) on the 24-hour BP response in individuais with T2D. Not to mention that it is not of our knowledge, studies that have investigated the effects of different aerobic exercise intesities on BP 24 hours in subjects with T2D.Additionally, Several studies have investigated the effects of different exercise modes ( e.g., aerobic vs. resistance ), intensities, and durations on BP responses during the post-exercise recovery period. Studies regarding the effects of different sports modalities, especially martial arts, have also been performed, such as: Tai Chi Chuan, Jiu Jitsu, and Judo. However, until now, no study has explored the BP responses after a single Contact Karate (CK) session. It is worth mentioning that the scientific literature related to combat sports has hardly been explored, especially regarding health-related variables (i.e., post-exercise BP reduction). Most studies have investigated performance-related parameters in athletes, making the evaluation of health-related variables (such as PEH) a scientific gap. Therefore, investigations related to this issue have been strongly encouraged. It should be noted that given the known complications of type 2 diabetes and characteristics of sport (high physical contact of high impact), it is wise to initially investigate the effects of a contact karate session on the blood pressure response after exercise in apparently healthy subjects and then, if possible, in special populations as diabetes and hypertension. With regard to chronic exercise, in particular the resistance exercise, the available literature concerning their effects on the response of NO and, in tum, on BP in individuais with T2D, it is still incipient. To the best of our knowledge, there have been only two randomized clinical trials ofRT's effects on NO concentration and BP levels in T2D patients, only one of which, verified the NO response (along with BP) due to R T. Therefore, there is an apparent lack of evidence on R T' s effects on the responses of NO and BP in T2D patients. Objectives: Study 1) to investigate and compare the responses of PKA, BK, desArg9-BK, NO and BP after a single session of moderate-intensity aerobic exercise in T2D and non-diabetic (ND) individuais; study 2) To verify the effects of different intensities of aerobic exercise on 24-hour ambulatory BP responses in individuais with T2D and prehypertension; study 3) to verify the effects of a Contact Karate (CK) session on BP responses during a post-exercise recovery period in young adults; study 4) to determine the effects of eight weeks RT on the responses of NO and BP in T2D patients and their controls peers. Methods: study l)Ten subjects with T2D and 10 Non-diabetics (ND) underwent three sessions: 1) maximal incremental test on cycle ergometer to determine lactate threshold (L T); 2) 20- min of constant-load exercise on cycle ergometer, at 90% LT and; 3) control session. BP and oxygen uptake were measured at rest and at 15, 30 and 45 min post-exercise. Venous blood samples were collected at 15 and 45 minutes of the recovery period for further analysis of PKA, BK and desArg9-BK. NO was analyzed at 15 minutes post exercise. Study 2) ten individuals with T2D and prehypertension completed three sessions applied in random order: non-exercise control (CON) and exercise at moderate (MOD) and maximal (MAX) intensities. Heart rate (HR), BP, blood lactate concentrations ([Lac ]), oxygen uptake (VO2), and rate of perceived exertion (RPE) were measured at rest, during the experimental sessions, and during the 60 min recovery period. After this period, ambulatory blood pressure was monitored for 24 h. Study 2) ten individuals with T2D and prehypertension completed three sessions applied in random order: non-exercise control (CON) and exercise at moderate (MOD) and maximal (MAX) intensities. Heart rate (HR), BP, blood lactate concentrations ([Lac ]), oxygen uptake (VO2), and rate of perceived exertion (RPE) were measured at rest, during the experimental sessions, and during the 60 min recovery period. After this period, ambulatory blood pressure was monitored for 24 h. Study 3) Thirty-two male CK athletes volunteered and underwent one CK session (50 min) anda control session. BP was measured during rest (before sessions), as well as on the 15th, 30th, 45th, and 60th min of the post-exercise recovery. Study 4) We performed eight-weeks of randomized controlled trial in T2D patients and ND individuals. After initial screening, were randomly allocated into four groups: (1) trained T2D (T2DTRAINED; n = 9), (2) trained ND (NDTRAINED; n = 10), (3) control T2D (T2DCON; n = 8) and (4) control ND (NDCON; n = 7). NO and BP were determined before and after the intervention. Results: study 1) The ND group presented PEH of systolic blood pressure (SBP) and mean arterial pressure (MAP) on the 90% L T session but T2D group did not. Plasma NO increased ~24.4% for ND and ~13.8% for T2D group 15min after the exercise session. Additionally, only ND individuais showed increases in PKA and BK in response to exercise and only T2D group showed increased desArg9-BK production. Study 2) Compared with CON, only MAX elicited post-exercise BP reduction that lasted for 8 h after exercise and during sleep. Study 3) The SBP, diastolic blood pressure, and MAP were significantly lower at the post-exercise period compared to pre-exercise rest (p<.05), with the largest reductions being observed at the 60th min of recovery and at the sarne periods of post-exercise recovery of the control session. Study 4) After eight weeks of RT (three times per week), the T2D and ND experimental groups decreased systolic blood pressure (SBP) by 7.0 and 3.4 mmHg, respectively. However, the control groups showed maintenance (0.24 mmHg for T2D) or elevation (2.2 mmHg for ND) of systolic blood pressure. Although none of these changes were significant (p > .05). As regards the absolute values of BP, T2D subjects who did not undergo the training (T2DCON) tended (p = .057) to have increase SBP and significantly (p = .05) increased MAP. Conclusions: studyl) it was concluded that T2D individuals presented lower PKA, BK and NOx release as well as higher desArg9-BK production and reduced PEH in relation to ND participants after a single exercise session. Study 2) A single session of aerobic exercise resulted in 24 h BP reductions in individuals with T2D, especially while sleeping, and this reduction seems to be dependent on the intensity of the exercise performed. Study 3) a single CK session can promote a decrease in BP for at least 60 min after performing this type of exercise in young adults. Study 4) eight weeks of RT does not increase NO concentrations and, in tum, does not reduce BP in T2D patients-though it prevented its increase. |
