Post-resistance exercise hypotension in patients with intermittent claudication

Cardiovascular and Autonomic Responses after a Single Bout of Resistance Exercise in Men with Untreated Stage 2 Hypertension

The aim of this paper is to assess the integrated responses of ambulatory blood pressure (BP), cardiac autonomic modulation, spontaneous baroreflex sensitivity (BRS), and vascular reactivity after a single bout of resistance exercise (RE) in men with stage 2 hypertension who have never been treated before. Ten hypertensive men were subjected to a RE session of three sets of 20 repetitions and an intensity of 40% of the 1-repetition maximum (RM) test in seven different exercises. For the control (CTR) session, the volunteers were positioned on the exercise machines but did not perform any exercise. Forearm blood flow was measured by venous occlusion plethysmography. We also analyzed the heart rate variability (HRV), ambulatory BP, blood pressure variability (BPV), and BRS. All measurements were performed at different timepoints: baseline, 20 min, 80 min, and 24 h after both RE and CTR sessions. There were no differences in ambulatory BP over the 24 h between the RE and CTR sessions. However, the area under the curve of diastolic BP decreased after the RE session. Heart rate (HR) and cardiac output increased for up to 80 and 20 min after RE, respectively. Similarly, forearm blood flow, conductance, and vascular reactivity increased 20 min after RE (p < 0.05). In contrast, HRV and BRS decreased immediately after exercise and remained lower for 20 min after RE. We conclude that a single bout of RE induced an increase in vascular reactivity and reduced the pressure load by attenuating AUC of DBP in hypertensive individuals who had never been treated with antihypertensive medications.

AORTIC POST-RESISTANCE EXERCISE HYPOTENSION IN PATIENTS WITH PERIPHERAL ARTERY DISEASE

ABSTRACT Introduction: A single session of resistance training decreases brachial blood pressure (BP) in patients with peripheral artery disease (PAD). However, it is not known whether similar responses occur in aortic BP, which is a better predictor of cardiovascular risk. Objective: This study aimed to analyze the effects of a single session of resistance training on aortic BP in PAD patients. Methods: This randomized, crossover, controlled trial involved 16 patients. All of them performed a session of resistance training (R - 3 x 10 reps in eight exercises, 5-7 on the OMNI Scale) and a control session (C - resting for 50 min). Before and after each session, aortic BP was assessed by applanation tonometry technique. Results: There was an increase in systolic (P<0.002) and mean (P<0.001) aortic BP in both sessions; however, higher increases were observed in C session (P<0.001). Additionally, diastolic aortic BP only increased after C session (P=0.004). The hypotensive effect of the exercise on systolic, diastolic, and mean aortic BP were -12±2, -6±2, and -7±2 mmHg, respectively. Conclusion: A single session of resistance training promoted a hypotensive effect on aortic BP of patients with PAD, indicating an acute reduction in cardiovascular risk in this population. Level of Evidence I; Therapeutic studies - Investigating the results of treatment.

Exercise for intermittent claudication

BACKGROUND

Exercise programmes are a relatively inexpensive, low-risk option compared with other, more invasive therapies for treatment of leg pain on walking (intermittent claudication (IC)). This is the fourth update of a review first published in 1998.

OBJECTIVES

Our goal was to determine whether an exercise programme was effective in alleviating symptoms and increasing walking treadmill distances and walking times in people with intermittent claudication. Secondary objectives were to determine whether exercise was effective in preventing deterioration of underlying disease, reducing cardiovascular events, and improving quality of life.

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist searched the Specialised Register (last searched 15 November 2016) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 10) via the Cochrane Register of Studies Online, along with trials registries.

SELECTION CRITERIA

Randomised controlled trials of an exercise regimen versus control or versus medical therapy for people with IC due to peripheral arterial disease (PAD). We included any exercise programme or regimen used for treatment of IC, such as walking, skipping, and running. Inclusion of trials was not affected by duration, frequency, or intensity of the exercise programme. Outcome measures collected included treadmill walking distance (time to onset of pain or pain-free walking distance and maximum walking time or maximum walking distance), ankle brachial index (ABI), quality of life, morbidity, or amputation; if none of these was reported, we did not include the trial in this review.

DATA COLLECTION AND ANALYSIS

For this update (2017), RAL and AH selected trials and extracted data independently. We assessed study quality by using the Cochrane 'Risk of bias' tool. We analysed continuous data by determining mean differences (MDs) and 95% confidence intervals (CIs), and dichotomous data by determining risk ratios (RRs) and 95% CIs. We pooled data using a fixed-effect model unless we identified significant heterogeneity, in which case we used a random-effects model. We used the GRADE approach to assess the overall quality of evidence supporting the outcomes assessed in this review.

MAIN RESULTS

We included two new studies in this update and identified additional publications for previously included studies, bringing the total number of studies meeting the inclusion criteria to 32, and involving a total of 1835 participants with stable leg pain. The follow-up period ranged from two weeks to two years. Types of exercise varied from strength training to polestriding and upper or lower limb exercises; supervised sessions were generally held at least twice a week. Most trials used a treadmill walking test for one of the primary outcome measures. The methodological quality of included trials was moderate, mainly owing to absence of relevant information. Most trials were small and included 20 to 49 participants. Twenty-seven trials compared exercise versus usual care or placebo, and the five remaining trials compared exercise versus medication (pentoxifylline, iloprost, antiplatelet agents, and vitamin E) or pneumatic calf compression; we generally excluded people with various medical conditions or other pre-existing limitations to their exercise capacity.Meta-analysis from nine studies with 391 participants showed overall improvement in pain-free walking distance in the exercise group compared with the no exercise group (MD 82.11 m, 95% CI 71.73 to 92.48, P < 0.00001, high-quality evidence). Data also showed benefit from exercise in improved maximum walking distance (MD 120.36 m, 95% CI 50.79 to 189.92, P < 0.0007, high-quality evidence), as revealed by pooling data from 10 studies with 500 participants. Improvements were seen for up to two years.Exercise did not improve the ABI (MD 0.04, 95% CI 0.00 to 0.08, 13 trials, 570 participants, moderate-quality evidence). Limited data were available for the outcomes of mortality and amputation; trials provided no evidence of an effect of exercise, when compared with placebo or usual care, on mortality (RR 0.92, 95% CI 0.39 to 2.17, 5 trials, 540 participants, moderate-quality evidence) or amputation (RR 0.20, 95% CI 0.01 to 4.15, 1 trial, 177 participants, low-quality evidence).Researchers measured quality of life using Short Form (SF)-36 at three and six months. At three months, the domains 'physical function', 'vitality', and 'role physical' improved with exercise; however this was a limited finding, as it was reported by only two trials. At six months, meta-analysis showed improvement in 'physical summary score' (MD 2.15, 95% CI 1.26 to 3.04, P = 0.02, 5 trials, 429 participants, moderate-quality evidence) and in 'mental summary score' (MD 3.76, 95% CI 2.70 to 4.82, P < 0.01, 4 trials, 343 participants, moderate-quality evidence) secondary to exercise. Two trials reported the remaining domains of the SF-36. Data showed improvements secondary to exercise in 'physical function' and 'general health'. The other domains - 'role physical', 'bodily pain', 'vitality', 'social', 'role emotional', and 'mental health' - did not show improvement at six months.Evidence was generally limited in trials comparing exercise versus antiplatelet therapy, pentoxifylline, iloprost, vitamin E, and pneumatic foot and calf compression owing to small numbers of trials and participants.Review authors used GRADE to assess the evidence presented in this review and determined that quality was moderate to high. Although results showed significant heterogeneity between trials, populations and outcomes were comparable overall, with findings relevant to the claudicant population. Results were pooled for large sample sizes - over 300 participants for most outcomes - using reproducible methods.

AUTHORS' CONCLUSIONS

High-quality evidence shows that exercise programmes provided important benefit compared with placebo or usual care in improving both pain-free and maximum walking distance in people with leg pain from IC who were considered to be fit for exercise intervention. Exercise did not improve ABI, and we found no evidence of an effect of exercise on amputation or mortality. Exercise may improve quality of life when compared with placebo or usual care. As time has progressed, the trials undertaken have begun to include exercise versus exercise or other modalities; therefore we can include fewer of the new trials in this update.

Acute Effects of T'ai Chi Chuan Exercise on Blood Pressure and Heart Rate in Peripheral Artery Disease Patients

OBJECTIVE

To investigate the acute effect of a t'ai chi chuan session on blood pressure and heart rate in patients with peripheral artery disease (PAD).

DESIGN

Randomized crossover intervention study.

SETTING

Outpatient therapy center.

PARTICIPANTS

Seven patients with PAD, aged 50-79 years, not using β-blockers, calcium-channel blockers, or nondihidropiridinic vasodilators.

INTERVENTION

T'ai chi chuan and control session (both sessions lasted 40 minutes).

OUTCOME MEASURES

Systolic and diastolic blood pressure and heart rate, which were evaluated before and after the intervention (10, 30, and 50 minutes).

RESULTS

T'ai chi chuan exercise acutely decreased systolic blood pressure at 30 minutes after exercise (p = 0.042) and increased diastolic blood pressure at 50 minutes after exercise (p = 0.041). Heart rate did not change after t'ai chi chuan exercise.

CONCLUSION

T'ai chi chuan acutely decreases systolic blood pressure in patients with PAD.

Training improves walking capacity and cardiovascular function in arteritis

Patients with arteritis have a high risk of mortality from cardiovascular disorders. However, whether these patients benefit from an intervention involving exercise remains unclear. In this study, we assessed the effects of an unsupervised exercise program on walking capacity, quality of life, and cardiovascular parameters of a patient with arteritis. A 33-year-old man reporting symptoms of claudication during walking was studied. Imaging tests revealed severe atherosclerosis and arteritis was diagnosed. Five weekly sessions of walking for 16 weeks increased claudication distance and total walking distance, produced improvements in six out of the eight health-related quality-of-life domains, decreased systolic blood pressure, and changed cardiac autonomic modulation toward parasympathetic modulation. This case report showed that unsupervised exercise training improved walking capacity, quality of life, and cardiovascular parameters in a patient with arteritis.

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.

Cardiovascular responses of peripheral artery disease patients during resistance exercise

BACKGROUND: Resistance training has been used for the treatment of patients with peripheral artery disease (PAD). However, cardiovascular responses during this type of exercise have not been fully elucidated in these patients. OBJECTIVES: To analyze the cardiovascular responses during resistance exercise and to verify whether there are any correlations between these responses and disease severity or blood pressure levels in patients with PAD. METHODS: Seventeen PAD patients performed one set of 10 repetitions of knee extension exercise with an intensity of 50% of one repetition maximum. The responses of systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were continuously monitored using the finger photoplethysmography technique. The rate-pressure product (RPP) was obtained by multiplication of SBP and HR. RESULTS: During the resistance exercises there were significant increases in SBP (126 ± 14 vs. 184 ± 20 mmHg, p<0.001), DBP (68 ± 8 vs. 104 ± 14 mmHg, p<0.001), HR (76 ± 18 vs. 104 ± 30 bpm, p<0.001) and RPP (9523 ± 2115 vs. 19103 ± 6098 mmHg x bpm, p<0.001). A negative correlation was observed between relative change (Δ) in SBP and SBP at rest (r =-0.549, p=0.022). On the other hand, there was no relationship between Δ SBP and the ankle-brachial index (r=0.076, p=0.771). CONCLUSION: Increases in cardiovascular variables were observed during resistance exercise in PAD patients. The highest increases occurred in patients with lower SBP levels at resting.

A single bout of resistance exercise does not modify cardiovascular responses during daily activities in patients with peripheral artery disease

OBJECTIVE

To analyze the posteffects of a single bout of resistance exercise on cardiovascular parameters in patients with peripheral artery disease (PAD).

DESIGN

Randomized cross-over.

MATERIALS AND METHODS

Seventeen PAD patients performed two experimental sessions: control (C) and resistance exercise (R). Both sessions were identical (eight exercises, 3×10 repetitions), except that the R session was performed with an intensity between 5 and 7 in the OMNI-RES scale and the C session was performed without any load. Systolic blood pressure (BP), diastolic BP, heart rate, and rate-pressure product (RPP) were measured for 1 h after the interventions in the laboratory and during 24-h using ambulatory BP monitoring.

RESULTS

After the R session, systolic BP (greatest reduction: -6±2 mmHg, P<0.01) and RPP (greatest reduction: -888±286 mmHg×bpm; P<0.01) decreased until 50 min after exercise. From the second hour until 23 h after exercise, BP, heart rate, and RPP product were similar (P>0.05) between R and C sessions. BP load, nocturnal BP fall, and morning surge were also similar between R and C sessions (P>0.05).

CONCLUSION

A single bout of resistance exercise decreased BP and cardiac work for 1 h after exercise under clinical conditions, and did not modify ambulatory cardiovascular variables during 24 h in patients with PAD.

Exercise for intermittent claudication

BACKGROUND

Exercise programmes are a relatively inexpensive, low-risk option compared with other more invasive therapies for leg pain on walking (intermittent claudication (IC)). This is an update of a review first published in 1998.

OBJECTIVES

The prime objective of this review was to determine whether an exercise programme in people with intermittent claudication was effective in alleviating symptoms and increasing walking treadmill distances and walking times. Secondary objectives were to determine whether exercise was effective in preventing deterioration of underlying disease, reducing cardiovascular events and improving quality of life.

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched September 2013) and CENTRAL (2013, Issue 8).

SELECTION CRITERIA

Randomised controlled trials of an exercise regimen versus control or versus medical therapy in people with IC due to peripheral arterial disease. Any exercise programme or regimen used in the treatment of intermittent claudication was included, such as walking, skipping and running. Inclusion of trials was not affected by the duration, frequency or intensity of the exercise programme. Outcome measures collected included treadmill walking distance (time to onset of pain or pain-free walking distance and maximum walking time or maximal walking distance), ankle brachial index (ABI), quality of life, morbidity or amputation; if none of these were reported the trial was not included in this review.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality.

MAIN RESULTS

Eleven additional studies were included in this update making a total of 30 trials which met the inclusion criteria, involving a total of 1816 participants with stable leg pain. The follow-up period ranged from two weeks to two years. The types of exercise varied from strength training to polestriding and upper or lower limb exercises; generally supervised sessions were at least twice a week. Most trials used a treadmill walking test for one of the outcome measures. Quality of the included trials was moderate, mainly due to an absence of relevant information. The majority of trials were small with 20 to 49 participants. Twenty trials compared exercise with usual care or placebo, the remainder of the trials compared exercise to medication (pentoxifylline, iloprost, antiplatelet agents and vitamin E) or pneumatic calf compression; people with various medical conditions or other pre-existing limitations to their exercise capacity were generally excluded.Overall, when taking the first time point reported in each of the studies, exercise significantly improved maximal walking time when compared with usual care or placebo: mean difference (MD) 4.51 minutes (95% confidence interval (CI) 3.11 to 5.92) with an overall improvement in walking ability of approximately 50% to 200%. Walking distances were also significantly improved: pain-free walking distance MD 82.29 metres (95% CI 71.86 to 92.72) and maximum walking distance MD 108.99 metres (95% CI 38.20 to 179.78). Improvements were seen for up to two years, and subgroup analyses were performed at three, six and 12 months where possible. Exercise did not improve the ABI (MD 0.05, 95% CI 0.00 to 0.09). The effect of exercise, when compared with placebo or usual care, was inconclusive on mortality, amputation and peak exercise calf blood flow due to limited data. No data were given on non-fatal cardiovascular events.Quality of life measured using the Short Form (SF)-36 was reported at three and six months. At three months, physical function, vitality and role physical all significantly improved with exercise, however this was a limited finding as this measure was only reported in two trials. At six months five trials reported outcomes of a significantly improved physical summary score and mental summary score secondary to exercise. Only two trials reported improvements in other domains, physical function and general health.Evidence was generally limited for exercise compared with antiplatelet therapy, pentoxifylline, iloprost, vitamin E and pneumatic foot and calf compression due to small numbers of trials and participants.

AUTHORS' CONCLUSIONS

Exercise programmes are of significant benefit compared with placebo or usual care in improving walking time and distance in people with leg pain from IC who were considered to be fit for exercise intervention.

Low-intensity resistance exercise does not affect cardiac autonomic modulation in patients with peripheral artery disease

OBJECTIVE

To analyze the effect of a single bout of resistance exercise on cardiac autonomic modulation in patients with peripheral artery disease.

METHODS

Fifteen patients with peripheral artery disease (age: 58.3±4.0 years) underwent the following sessions in a random order: resistance exercise (three sets of 10 repetitions of the six resistance exercises with a workload of 5-7 in the OMNI-RES scale) and control (similar to the resistance session; however, the resistance exercises were performed with no load). The frequency domain (low frequency, high frequency and sympathovagal balance) and symbolic analysis (0V, 1V and 2V patterns) of heart rate variability were obtained before and until one hour after the interventions.

RESULTS

After the resistance exercise and control sessions, similar increases were observed in the consecutive heartbeat intervals (control: 720.8±28.6 vs. 790.9±34.4 ms; resistance exercise: 712.9±30.1 vs. 756.8±37.9 ms; p<0.05) and in the pattern of the symbolic analysis with no variation (0V) (control: 25.1±3.5 vs. 33.4±4.1%; resistance exercise: 26.1±3.2 vs. 29.7±3.5%; p<0.05) until 50 min after both interventions. The pattern of two variations (2V) decreased similarly (control: 11.2±2.1 vs. 8.3±2.1%; resistance exercise: 9.5±1.7 vs. 7.8±1.7%; p<0.05). In contrast, the pattern of one variation (1V), the low and high frequency bands and sympathovagal balance did not change after the interventions (p>0.05).

CONCLUSION

A single bout of resistance exercise did not alter cardiac autonomic modulation in patients with peripheral artery disease.

Exercise and its interactions with various aspects of man and animal lives

To review recently published papers in the Brazilian Scientific press on the general subject of physical exercise. All articles published in 2010/2011 found through the keyword exercise were collected from 11 Brazilian Journals. They were hand filtered to exclude all but original research papers. They were grouped according to subject categories and subcategories. A brief summary of all included articles was produced, comparing similar articles between them. The most commonly found interactions refer to exercise vs. the cardiovascular system, metabolism and the locomotor system, in this order. The volume of scientific research in the field is high and of sufficient quality to justify highlighting.

Efeitos agudos de uma sessão de reabilitação cardíaca sobre a pressão arterial

INTRODUÇÃO: Hipertensão arterial é uma condição mórbida presente em grande parte dos adultos. Estudos evidenciam que exercícios físicos de moderada intensidade e curta duração têm efeitos satisfatórios na redução da pressão arterial. OBJETIVO: Mensurar a duração do efeito hipotensor de uma única sessão de reabilitação cardíaca a partir da prática de exercício aeróbico de curta duração e moderada intensidade. MATERIAIS E MÉTODOS: O estudo foi prospectivo e quase-experimental. Participaram do estudo nove voluntários hipertensos e sedentários (cinco do sexo feminino e quatro do masculino), monitorizados pelo exame de medida ambulatorial da pressão arterial por 12 horas e 30 minutos. Foi realizada uma única sessão de treinamento aeróbico por dez minutos em bicicleta ergométrica numa intensidade moderada. RESULTADOS: Houve redução tanto na PAS (pressão arterial sistólica) como na PAD (pressão arterial diastólica) (ANOVA, p < 0,001) durante as 12 horas de estudo. CONCLUSÃO: Uma sessão de exercício físico de curta duração com intensidade moderada foi suficiente para reduzir os níveis pressóricos dos voluntários analisados por um período de 12 horas.

Triagem pré-participação em exercício físico em pacientes com doença arterial periférica

CONTEXTO: Os indivíduos com doença arterial periférica (DAP) apresentam alto risco de doença cardiovascular. Dessa forma, é imprescindível que os instrumentos de triagem pré-participação em exercício indiquem quais pacientes com DAP devem realizar avaliação cardiovascular antes de iniciar o programa de exercício. OBJETIVO: Comparar a sensibilidade de dois instrumentos de triagem pré-participação em exercício para identificação de indivíduos com DAP. MÉTODOS: Vinte e oito pacientes com DAP de ambos os sexos responderam ao questionário de prontidão para a atividade física (PAR-Q) e um questionário de estratificação do risco cardiovascular (QERC) baseado nas diretrizes do American College of Sports Medicine. RESULTADOS: O PAR-Q mostrou que a questão seis (Algum médico já recomendou o uso de medicamentos para a sua pressão arterial ou condição cardiovascular?) foi a que apresentou maior frequência de respostas positivas (82,1%). Considerando todas as respostas, cinco indivíduos não tiveram nenhuma positiva ao questionário (17,9%), indicando que estariam aptos para a prática de atividade física. Os resultados do QERC mostraram que as questões 11 (Você sente queimação ou sensação de câimbras em suas pernas quando faz caminhada?) e 2 (Algum médico já falou que você tem pressão alta?) apresentaram a maior frequência de respostas positivas (82,1%). CONCLUSÕES: Segundo o QERC, todos os indivíduos da amostra foram considerados com alto risco cardiovascular. O PAR-Q não foi sensível o suficiente para identificar todos os sujeitos, ao passo que o QERC identificou todos os indivíduos. Assim, sugere-se a utilização do QERC para identificação de indivíduos com DAP.