Stages of health behavior change and factors associated with physical activity in patients with intermittent claudication

OBJECTIVE: To analyze, in people with intermittent claudication, the frequency of individuals who are in each of stages of health behavior change to practice physical activity, and analyze the association of these stages with the walking capacity. METHODS: We recruited 150 patients with intermittent claudication treated at a tertiary center, being included those > 30-year-old-individuals and who had ankle-arm index < 0.90. We obtained socio-demographic information, presence of comorbidities and cardiovascular risk factors and stages of health behavior change to practice physical activity through a questionnaire, they being pre-contemplation, contemplation, preparation, action and maintenance. Moreover, the walking capacity was measured in a treadmill test (Gardner protocol). RESULTS: Most individuals were in the maintenance stage (42.7%), however, when the stages of health behavior change were categorized into active (action and maintenance) and inactive (pre-contemplation, contemplation and preparation), 51.3% of the individuals were classified as inactive behavior. There was no association between stages of health behavior change, sociodemographic factors and cardiovascular risk factors. However, patients with intermittent claudication who had lower total walking distance were three times more likely to have inactive behavior. CONCLUSION: Most patients with intermittent claudication showed an inactive behavior and, in this population, lower walking capacity was associated with this behavior

Strength and power training did not modify cardiovascular responses to aerobic exercise in elderly subjects

Resistance training increases muscle strength in older adults, decreasing the effort necessary for executing physical tasks, and reducing cardiovascular load during exercise. This hypothesis has been confirmed during strength-based activities, but not during aerobic-based activities. This study determined whether different resistance training regimens, strength training (ST, constant movement velocity) or power training (PT, concentric phase performed as fast as possible) can blunt the increase in cardiovascular load during an aerobic stimulus. Older adults (63.9 ± 0.7 years) were randomly allocated to: control (N = 11), ST (N = 13, twice a week, 70-90% 1-RM) and PT (N = 15, twice a week, 30-50% 1-RM) groups. Before and after 16 weeks, oxygen uptake (VO2), systolic blood pressure (SBP), heart rate (HR), and rate pressure product (RPP) were measured during a maximal treadmill test. Resting SBP and RPP were similarly reduced in all groups (combined data = -5.7 ± 1.2 and -5.0 ± 1.7%, respectively, P < 0.05). Maximal SBP, HR and RPP did not change. The increase in measured VO2, HR and RPP for the increment in estimated VO2 (absolute load) decreased similarly in all groups (combined data = -9.1 ± 2.6, -14.1 ± 3.9, -14.2 ± 3.0%, respectively, P < 0.05), while the increments in the cardiovascular variables for the increase in measured VO2 did not change. In elderly subjects, ST and PT did not blunt submaximal or maximal HR, SBP and RPP increases during the maximal exercise test, showing that they did not reduce cardiovascular stress during aerobic tasks.Universidade de São Paulo Escola de Educação Física e Esporte Laboratório de Hemodinâmica da Atividade MotoraUniversidade de São Paulo Escola de Educação Física e Esporte Laboratório de Adaptação Neuromuscular ao Treinamento de ForçaUniversidade Federal de São Paulo (UNIFESP) Centro de Estudos em Psicobiologia e ExercícioUNIFESP, Centro de Estudos em Psicobiologia e ExercícioSciEL

Walking training improves ambulatory blood pressure variability in claudication

Background: Walking training (WT) improves walking capacity and reduces clinic blood pressure (BP) in patients with peripheral artery disease (PAD), but its effects on ambulatory BP remains unknown. Objectives: To investigate the effect of 12 weeks of WT on ambulatory BP and its variability in patients with PAD. Methods: Thirty-five male patients with PAD and claudication symptoms were randomly allocated into two groups: control (n = 16, 30 min of stretching) and WT (n = 19, 15 bouts of 2 min of walking at the heart rate of leg pain threshold interspersed by 2 min of upright rest). Before and after 12 weeks, 24-hour ambulatory BP was assessed. Ambulatory BP variability indices assessed at both time points included the 24-hour standard deviation (SD24), the awake and asleep weighted standard deviation (SDdn), and the 24-hour average real variability (ARV24). Data were analyzed by mixed two-way ANOVAs, considering P<0.05 as significant. Results: After 12 weeks, neither group had significant changes in 24-hour, awake and sleep BPs. The WT decreased systolic and mean BP variabilities (Systolic BP – 13.3±2.8 vs 11.8±2.3, 12.1±2.84 vs 10.7±2.5 and 9.4±2.3 vs 8.8±2.2 mmHg); Mean BP – 11.0±1.7 vs 10.4±1.9, 10.1±1.6 vs 9.1±1.7 and 8.0.±1.7 vs 7.2±1.5 mmHg for SD24, SDdn and ARV24, respectively). Neither group had significant changes in diastolic BP variabilities after 12 weeks. Conclusion: The WT does not change ambulatory BP levels but decreases ambulatory BP variability in patients with PAD. This improvement may have a favorable impact on the cardiovascular risk of patients with symptomatic PAD

Predictors of walking capacity in peripheral arterial disease patients

OBJECTIVE: To estimate walking capacity in intermittent claudication patients through a prediction model based on clinical characteristics and the walking impairment questionnaire. METHODS: The sample included 133 intermittent claudication patients of both genders aged between 30 and 80 years. Data regarding clinical characteristics, the walking impairment questionnaire and treadmill walking test performance were obtained. Multiple regression modeling was conducted to predict claudication onset distance and total walking distance using clinical characteristics (age, height, mass, body mass index, ankle brachial index lower, gender, history of smoking and co-morbid conditions) and walking impairment questionnaire responses. Comparisons of claudication onset distance and total walking distance measured during treadmill tests and estimated by a regression equation were performed using paired t-tests. RESULTS: Co-morbid conditions (diabetes and coronary artery disease) and questions related to difficulty in walking short distances (walking indoors - such as around your house and walking 5 blocks) and at low speed (walking 1 block at average speed - usual pace) resulted in the development of new prediction models high significant for claudication onset distance and total walking distance (p;0.05) were observed. CONCLUSION: The current study demonstrated that walking capacity can be adequately estimated based on co-morbid conditions and responses to the walking impairment questionnaire

Stages of health behavior change and factors associated with physical activity in patients with intermittent claudication

OBJECTIVE: To analyze, in people with intermittent claudication, the frequency of individuals who are in each of stages of health behavior change to practice physical activity, and analyze the association of these stages with the walking capacity. METHODS: We recruited 150 patients with intermittent claudication treated at a tertiary center, being included those &gt;30-year-old-individuals and who had ankle-arm index <0.90. We obtained socio-demographic information, presence of comorbidities and cardiovascular risk factors and stages of health behavior change to practice physical activity through a questionnaire, they being pre-contemplation, contemplation, preparation, action and maintenance. Moreover, the walking capacity was measured in a treadmill test (Gardner protocol). RESULTS: Most individuals were in the maintenance stage (42.7%), however, when the stages of health behavior change were categorized into active (action and maintenance) and inactive (pre-contemplation, contemplation and preparation),51.3% of the individuals were classified as inactive behavior. There was no association between stages of health behavior change, sociodemographic factors and cardiovascular risk factors. However, patients with intermittent claudication who had lower total walking distance were three times more likely to have inactive behavior. CONCLUSION: Most patients with intermittent claudication showed an inactive behavior and, in this population, lower walking capacity was associated with this behavior

Relacao entre o nivel de atividade fisica estimado pelo Baltimore Activity Scale for Intermittent Claudication e a pedometria em pacientes com claudicacao intermitente

CONTEXTO: Os pacientes com claudicação intermitente apresentam níveis reduzidos de atividade física. A Baltimore Activity Scale for Intermittent Claudication (BASIC) foi validada para quantificar o nível de atividade física destes pacientes. No entanto, esta validação se baseou em apenas dois dias de monitoramento com acelerômetros, de modo que ainda permanece incerto se a BASIC fornece informações sobre os níveis de atividade física semanal. OBJETIVO: Analisar a correlação entre o nível de atividade física estimada pela BASIC e o nível obtido pelo pedômetro em uma semana, em pacientes com claudicação intermitente. MÉTODOS: Foram estudados 150 pacientes com claudicação intermitente, com idade entre 30 e 80 anos. Foram obtidos os dados sociodemográficos e verificada a presença de comorbidades e de fatores de risco cardiovascular, e a BASIC. O pedômetro foi utilizado por sete dias consecutivos, sendo a análise feita em três diferentes períodos de monitorização (todos os dias, dias da semana e do fim de semana). RESULTADOS: Foi observada correlação entre a BASIC e a média de passos de todos os dias (rho=0,343; p<0,001), dos dias de semana (rho=0,336; p<0,001) e dos dias do final de semana (rho=0,317; p<0,001). CONCLUSÃO: Em pacientes com claudicação intermitente, o nível de atividade física estimado pela BASIC se correlaciona com o nível de atividade física semanal

Effect of walking training on cardiovascular risk, function and regulation in patients with intermittent claudication

O treinamento de caminhada (TC) é recomendado para o tratamento de indivíduos com claudicação intermitente (CI) porque melhora a capacidade de caminhada. Além disso, seria interessante que o TC também promovesse modificações benéficas no sistema cardiovascular, pois os eventos cardiovasculares são a principal causa de morte nestes indivíduos. No entanto, os efeitos cardiovasculares do TC em indivíduos com CI foi pouco estudado. Assim, o objetivo deste estudo foi verificar o efeito do TC sobre o risco, a função e a regulação cardiovasculares em indivíduos com CI. Quarenta e dois indivíduos com CI foram divididos de forma aleatória em 2 grupos: controle (GC, n=20, sessões de 30 min de alongamento) e treinamento de caminhada (GT, n=22, 15 séries de 2 min de caminhada em intensidade correspondente à frequência cardíaca (FC) do limiar de dor intercalados por 2 min de repouso passivo). Nos dois grupos, a intervenção foi realizada 2 vezes/semana durante 12 semanas consecutivas. No início e ao final do estudo, os indivíduos realizaram as seguintes avaliações: glicemia e perfil lipídico de jejum; índice de massa corporal; capacidade de caminhada; consumo de oxigênio no 1º estágio e no pico do teste de esforço; índice tornozelo-braço (ITB) de repouso; janela isquêmica após teste ergoespirométrico; pressão arterial (PA) em repouso (auscultatória) e de 24 horas (oscilométrica); débito cardíaco (DC - reinalação de CO2); FC (ECG); volume sistólico (VS); resistência vascular (RV) sistêmica, do antebraço e da perna (plestismografia); componentes de alta (AF) e baixa (BF) frequência da variabilidade da FC; e sensibilidade barorreflexa espontânea (SBR). Mudanças significantes (P<0,05) ao longo do tempo e entre os grupos foram verificadas pela análise de variância ANOVA de dois fatores para medidas repetidas. O TC aumentou significantemente a capacidade de caminhada (&Delta;=+302±85m) e a SBR (&Delta;=+2.13±1.07 ms/mmHg), e diminuiu o VO2) no 1º estágio do teste (&Delta;=-1,8±0,4ml.kg-1.min-1), a janela isquêmica (&Delta;=- 0,40±0,38mmHg.min.m-1), a PA média (&Delta;=-5±2mmHg), a variabilidade da PA média de 24h (&Delta;=-0,8±0,2mmHg), o DC (&Delta;=-0.37±0.24L/min), a FC (&Delta;=- 4±2bpm), a RV do antebraço (&Delta;=-8.5±2.8 U) e a razão BF/AF (&Delta;=-1.24±0.99). A glicemia, o perfil lipídico, o índice de massa corporal, o VO2) pico, o ITB de repouso e a RV sistêmica e da perna não foram modificadas pelo TC. Não houve mudança em nenhuma variável no GC. Em conclusão, o TC melhorou a capacidade de caminhada, a economia de caminhada e a janela isquêmica. Além disso, o TC melhorou a função (PA, DC, FC e RV antebraço) e a regulação (BF/AF e SBR) cardiovasculares em indivíduos com CI. Estas alterações fornecem suporte adicional para a utilização do TC no tratamento de indivíduos com CIWalking training (WT) is recommended for the treatment of patients with intermittent claudication (IC) because it improves walking capacity. Moreover, it would be interesting that WT also promotes beneficial changes on cardiovascular system, since cardiovascular events are the main causes of death in these patients. Nevertheless, the effects of WT on cardiovascular system in patients with IC have been poorly studied. Thus, the objective of this study was to investigate the effects of WT on cardiovascular risk, function and regulation in patients with IC. Forty-two IC patients were randomly divided into 2 groups: Control (CG, n=20, 30 min of stretching exercises) and walking training (TG, n=22, 15 sets of 2:2-min walk:rest at the heart rate (HR) of pain threshold). In both groups, the intervention was performed twice/week for 12 consecutive weeks. At the beginning and end of the study, the following measured were done: fasting glycemia and lipid profile; body mass index; walking capacity; VO2 at the first stage and the peak of a treadmill test; ankle brachial index (ABI); ischemic window after maximal test; resting (auscultatory) and 24-hour (oscillometric) blood pressure (BP); cardiac output (CO - CO2 rebreathing); heart rate (HR - ECG); stroke volume (SV); systemic, forearm and leg vascular resistance (VR - plethysmography); low- (LF) and high-frequency (HF) components of HR variability; and spontaneous baroreflex sensitivity (SBS). Significant changes (P<0.05) over time and between groups were assessed by 2-way ANOVA for repeated measures. WT significantly increased walking capacity (&Delta;=+302±85m) and SBS (&Delta;=+2.13±1.07 ms/mmHg), and decreased VO2 at the first stage of treadmill test (&Delta;=-1.8±0.4ml.kg-1.min-1), ischemic window (&Delta;=-0.40±0.38mmHg.min.m-1), mean BP (&Delta;=-5±2mmHg), ambulatory mean BP variability (&Delta;=-0,8±0,2 mmHg), CO (&Delta;=-0.37±0.24 L/min), HR (&Delta;=- 4±2bpm), forearm VR (&Delta;=-8.5±2.8 U) and LF/HF (&Delta;=-1.24±0.99). Glycemia, lipid profile, body mass index, VO2 peak, ABI, systemic and leg VR were unchanged following WT. There was no significant change for any variable in CG. In conclusion, WT enhanced walking capacity, walking economy and ischemic window. In addition, WT improved cardiovascular function (BP, CO, HR and forearm VR) and autonomic regulation (LF/HF, SBS) in patients with IC. These changes provide further support for the use of regular WT in treating patients with I

Post-walking exercise hypotension in patients with intermittent claudication

Purpose - This study aimed to investigate the acute effect of intermittent walking exercise (WE) on blood pressure (BP) responses in patients with intermittent claudication (IC). Secondly, this study aimed to gain improved insight into the physiological mechanisms controlling BP regulation after intermittent WE in this patient group. Methods - Twenty patients with IC participated in two experimental sessions in a random order, as follows: WE (15 × 2-min bouts of WE interpolated with 2-min rest intervals) and control (standing rest on a treadmill for 60 min). BP, cardiac output (CO: CO2 rebreathing), and cardiovascular autonomic modulation (spectral analysis of HR variability) were assessed before and after both experimental sessions during supine rest, and stroke volume (SV) and systemic vascular resistance (SVR) were calculated. Data were analyzed using two-way ANOVA. Results - WE decreased systolic, diastolic, and mean BP, with net effects of -13 ± 2, -5 ± 2, and -7 ± 2 mm Hg versus control, respectively (all P < 0.05). WE also decreased SV (-5.62 ± 1.97 mL, P < 0.05) and CO (-0.05 ± 0.13 L·min(-1), P < 0.05) versus preintervention and prevented the observed increase in SVR in the control condition (+4.2 ± 1.4 U, P < 0.05). HR showed a decrease (P < 0.05), consistent with evidence of increased vagal modulation, in the control condition. BP measurements over the subsequent 24 h were similar between experimental conditions. Conclusions - In patients with IC, WE induced a postexercise hypotension response that had a significant magnitude versus control but was not maintained over the next 24 h of daily activities. The acute postexercise hypotension response was mediated by a decrease in CO and SV, which was not compensated by an augmentation of SVR, as observed in the control arm of the study

Comparação entre os métodos subjetivo e objetivo para avaliação da capacidade funcional durante tratamento clínico em pacientes com claudicação intermitente

OBJETIVO: Verificar se há relação entre a medida da capacidade funcional avaliada subjetiva e objetivamente em relação ao estado atual e após tratamento clínico em pacientes com claudicação intermitente. MÉTODOS: Foram recrutados 500 pacientes com claudicação intermitente. Todos realizaram exame clínico e foram submetidos a uma avaliação funcional por meio do método subjetivo (consulta clínica) e objetivo (teste de esteira). Adicionalmente, 50 pacientes foram selecionados para se avaliar o efeito do tratamento clínico, pelos métodos subjetivo e objetivo, em relação à capacidade funcional. RESULTADOS: Dos 500 pacientes selecionados, somente 60 (12,0%) apresentaram valores referidos e observados similares. Os demais pacientes, ou seja, 440 (88,0%) apresentaram valores relatados discordantes em relação àqueles obtidos no teste de esforço. Com relação ao efeito do tratamento clínico em relação à capacidade funcional, os resultados foram similares entre ambos os métodos (&#967;²=1,7; p=0,427). CONCLUSÃO: Apesar de o método subjetivo superestimar os valores de capacidade funcional, quando comparados ao método objetivo, não foram observadas diferenças significantes entre ambos os métodos, quando se analisou o efeito do tratamento clínico. Assim, o método subjetivo fornece informações similares em comparação à medida objetiva no acompanhamento do tratamento clínico de pacientes com claudicação intermitente