Thesis (MScSportSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: There are extensive literature on the PEH response after acute and chronic aerobic and resistance exercise, as well as a few studies on concurrent and water exercise. However, there is comparatively little evidence that high intensity interval training (HIIT) elicits similar post exercise blood pressure reductions (PEH) compared to other types of exercise. Furthermore, it is difficult to quantify the magnitude of the hypotensive response following these exercises, due to variations in exercise protocols in terms of intensity and duration. Both these training variables are considered important determinants of the magnitude and duration of the PEH response. The current study determined the magnitude of the PEH response after an acute bout and six sessions of HIIT, and the effects after two weeks of detraining in overweight/obese young women. Twenty young women (aged 21 ± 2 years) volunteered for the study. All the subjects were normotensive (SBP: 119.2 ± 5.6 mmHg and DBP: 78.8 ± 4.1 mmHg). Subjects performed six sessions of HIIT within two weeks and detrained for two weeks. SBP, DBP, MAP and HR were monitored during seated recovery after exercise for 60 min to determine the change from resting values. The overall outcome showed that an acute HIIT session resulted in a reduction of 2.9 mmHg in SBP which approached near clinical significance, while six sessions of HIIT caused a clinically significant reduction of 5.3 mmHg; this response was almost totally reversed after detraining. There were no clinically significant reductions in DBP after the acute or six sessions of HIIT (1.7 and 2.7 mmHg, respectively). However, a clinically significant hypotensive response of 3.9 mmHg was sustained after detraining following the maximal exercise capacity test. MAP also reduced by a magnitude of 2.3 and 5.6 mmHg, respectively, after the acute bout and six sessions of HIIT, and detraining values were still 2.9 mmHg lower than resting values and approached near clinical significance. The results indicate that both an acute bout and six sessions of HIIT elicited a meaningful PEH response. However, the six sessions of HIIT caused a clinically significant reduction which was approximately twice the acute session. Likewise, detraining showed clinically significant effects in DBP and MAP, but SBP returned to near baseline values. This suggests that in only two weeks, the accumulated effects of six sessions of HIIT elicited a greater hypotensive response than after an acute session of HIIT. / AFRIKAANSE OPSOMMING: Daar is omvattende literatuur oor die post-oefening hipotensie (POH) na afloop van akute en kroniese aërobiese en weerstandsoefeninge, asook enkele studies oor gelyktydige krag- en uithouvermoë- en wateroefeninge. Daar is egter relatief min bewyse dat hoë intensiteit interval oefening (HIIO) soortgelyke post-oefening afnames in bloeddruk (POH) in vergelyking met ander tipes oefening veroorsaak. Voorts is dit moeilik om die omvang van die hipotensiewe respons na afloop van oefening te kwantifiseer, hoofsaaklik as gevolg van die variasies in oefeningprotokolle in terme van intensiteit en tydsduur. Beide hierdie inoefeningveranderlikes word as belangrike determinante van die omvang en die tydsduur van die POH respons beskou. Die huidige studie het die omvang van die POH respons na ʼn akute sessie en ses sessies HIIO, en die gevolge na afloop van twee weke se nie-inoefening (“detraining”) by oorgewig/vetsugtige jong dames, bepaal. Twintig jong dames (ouderdom 21 ± 2 jaar) het vrywillig ingestem om aan die studie deel te neem. Al die deelnemers was normotensief (SBD: 119.2 ± 5.6 mmHg en DBD: 78.8 ± 4.1 mmHg). Die deelnemers het ses sessies HIIO binne twee weke voltooi en het daarna vir twee weke geen inoefeningsessies gehad nie. SBD, DBD, GAD en HS is tydens ʼn sittende herstelfase vir 60 minute gemonitor om die verandering vanaf rustende waardes te bepaal. Die algehele uitkoms toon dat ʼn akute HIIO sessie ʼn afname van 2.9 mmHg in SBD tot gevolg gehad het wat aan kliniese betekenisvolheid grens, terwyl ses sessies van HIIO ʼn klinies betekenisvolle afname van 5.3 mmHg veroorsaak het; hierdie respons wat bykans volledige omgekeerd na die twee weke met geen inoefening. DBD het geen kliniese betekenisvolle afname na afloop van die akute of ses sessies van HIIO getoon nie (1.7 en 2.7 mmHg, respektiewelik). ʼn Klinies betekenisvolle hipotensiewe respons van 3.9 mmHg is egter gevind na die geen inoefeningsperiodes. GAD het ook met ʼn omvang van 2.3 en 5.6 mmHg, respektiewelik, verminder na afloop van die akute sessie en ses sessies van HIIO. Die geen inoefening waardes was steeds 2.9 mmHg laer as die rustende waardes en het aan kliniese betekenisvolheid gegrens. Die resultate toon dat beide ʼn akute sessie en ses sessies van HIIO ʼn betekenisvolle POH respons ontlok het. Ses sessies van HIIO het egter ʼn klinies betekenisvolle afname, wat ongeveer twee keer soveel as die afname van die akute sessie was, veroorsaak. In dieselde lig het ʼn twee weke geen inoefeningsperiode steeds klinies betekenisvolle veranderinge in DBD en GAD getoon, maar SBD het tot naby aan die basislyn waardes teruggekeer. Hierdie resultate suggereer dat in slegs twee weke die geakkumuleerde effekte van ses sessies van HIIO ʼn groter hipotensiewe respons as na ʼn akute sessie van HIIO ontlok het.

Aerobic exercise is well established in the literature as one of the non-pharmacological interventions in the treatment of hypertension. There is some controversy about resistance training and there is a paucity of evidence about sports such as Pilates. Because it is a widespread and practiced activity, it is necessary to know their hemodynamic responses and if there is possibility of post-exercise hypotension. Objective: To analyze the acute hemodynamic responses and to verify the occurrence of hypotension and mitigation of pressure reactivity after a Pilates session, and analyze if breathing is an active component in these responses. Method: 30 women (63.7 ± 5.8 years) were randomized into three groups (n = 10), which underwent a Pilates session with the respiratory component, the respiratory component and not only the breathing exercises each. The following variables were analyzed in the pre- and post-exercise period: Systolic and Diastolic Blood Pressure, FC and Reactivity pressure, and BMI, waist circumference, hip and abdomen. Results: The results show that one Pilates session is not able to significantly reduce BP in hypertensive subjects, nor ease the pressure reactivity. Besides, specific breathing technique of the method appears not to be an active component in reducing blood pressure. Although there was no statistical significance of these results, we believe that the amplitudes of found mitigations are relevant, since resemble those caused reductions by an anti-hypertensive medication class or for nutritional education and these minimum reductions in SBP are associated with decreased the risk of mortality from cardiovascular disease. / Já é bem estabelecido na literatura que o exercício aeróbio pode ser utilizado como uma das intervenções não farmacológicas no tratamento da hipertensão arterial. Existem algumas controvérsias a respeito do treinamento resistido e há uma escassez de evidências a respeito de modalidades como o Pilates. Por ser uma atividade amplamente difundida e praticada, torna-se necessário conhecer suas influências hemodinâmicas e se há hipotensão pós-exercício. Objetivo: Analisar as alterações hemodinâmicas agudas e verificar a ocorrência de hipotensão e atenuação da reatividade pressórica após uma sessão de Pilates, além de analisar se a respiração é um componente ativo nessas respostas. Métodos: 30 mulheres (63,7±5,8 anos) foram randomizadas em três grupos (n=10), os quais realizaram uma sessão de Pilates (1) com o componente respiratório, (2) sem o componente respiratório e (3) somente os exercícios respiratórios. As variáveis seguintes foram analisadas no período pré- e pós-exercício: Pressão Arterial Sistólica e Diastólica, FC e Reatividade Pressórica, além de IMC, circunferências de cintura, quadril e abdome. Resultados: Os resultados mostram que uma única sessão de Pilates não é capaz de reduzir significativamente a PA de mulheres idosas hipertensas, tampouco atenuar a reatividade pressórica. Além disso, a técnica respiratória específica do método não mostrou ser um componente ativo na redução da pressão arterial. Embora não tenha havido significância nesses resultados, consideramos que as amplitudes das atenuações encontradas sejam relevantes, uma vez que se assemelham às reduções provocadas por uma classe de medicação anti-hipertensiva e estas reduções mínimas da PAS estão associadas com a diminuição do risco de mortalidade por doenças cardiovasculares.