Vascular Mechanisms of Post-exercise Blood Pressure Responses in Peripheral Artery Disease

Characterizing the interindividual postexercise hypotension response for two order groups of concurrent training in patients with morbid obesity

Background: Postexercise hypotension (PEH) is a common physiological phenomenon occurring immediately after endurance training (ET), resistance training (RT), and ET plus RT, also termed concurrent training (CT); however, there is little knowledge about the interindividual and magnitude response of PEH in morbidly obese patients.

Aim: The aims of this study were (1) to investigate the effect of CT order (ET + RT vs. RT + ET) on the blood pressure responses; 2) characterize these responses in responders and nonresponders, and 3) identify potential baseline outcomes for predicting blood pressure decreases as responders.

Methods: A quasi-experimental study developed in sedentary morbidly obese men and women (age 43.6 ± 11.3 years; body mass index [BMI] ≥40 kg/m²) was assigned to a CT group of ET plus RT (ET + RT; n = 19; BMI 47.8 ± 16.7) or RT plus ET order group (RT + ET; n = 17; BMI 43.0 ± 8.0). Subjects of both groups received eight exercise sessions over four weeks. Primary outcomes include systolic (SBP), diastolic (DBP), mean arterial pressure [MAP], heart rate at rest [HR], and pulse pressure [PP] measurements before and after 10 min post-exercise. Secondary outcomes were other anthropometric, body composition, metabolic, and physical fitness parameters. Using the delta ∆SBP reduction, quartile categorization (Q) in “high” (Rs: quartile 4), “moderate” (MRs: quartile 3), “low” (LRs: quartile 2), and “nonresponders” (NRs: quartile 1) was reported.

Results: Significant pre–post changes were observed in ET + RT in session 2 for SBP (131.6 vs. 123.4 mmHg, p = 0.050) and session 4 (131.1 vs. 125.2 mmHg, p = 0.0002), while the RT + ET group showed significant reductions in session 4 (134.2 vs. 125.3 mmHg, p < 0.001). No significant differences were detected in the sum of the eight sessions for SBP (∑∆SBP) between ET + RT vs. RT + ET (−5.7 vs. −4.3 mmHg, p = 0.552). Interindividual analyses revealed significant differences among frequencies comparing Q1 “NRs” (n = 8; 22.2%), Q2 “LRs” (n = 8; 22.2%), Q3 “MRs” (n = 9; 25.0%), and Q4 “HRs” (n = 11; 30.5%), p < 0.0001. Quartile comparisons showed significant differences in SBP changes (p = 0.035). Linear regression analyses revealed significant association between ∑∆SBP with body fat % (β –3.826, R² 0.211 [21.1%], p = 0.031), skeletal muscle mass [β –2.150, R² 0.125 (12.5%), p = 0.023], fasting glucose [β 1.273, R² 0.078 (7.8%), p = 0.003], triglycerides [β 0.210, R² 0.014 (1.4%), p = 0.008], and the 6-min walking test [β 0.183, R² 0.038 (3.8%), p = 0.044].

Conclusion: The CT order of ET + RT and RT + ET promote a similar ‘magnitude’ in the postexercise hypotensive effects during the eight sessions of both CT orders in 4 weeks of training duration, revealing “nonresponders” and ‘high’ responders that can be predicted from body composition, metabolic, and physical fitness outcomes.

Concurrent training and interindividual response in women with a high number of metabolic syndrome risk factors

The non-responders (NRs) after exercise training have been poorly studied in populations with morbid obesity. The purpose of this study was to determine the NR prevalence after 20 weeks of concurrent training of morbidly obese women with a high or low number of metabolic syndrome (MetS) risk factors. Twenty-eight women with morbid obesity participated in an exercise training intervention and were allocated into two groups distributed based on a high (≥3, n = 11) or low number (<3, n = 17) of MetS risk factors. The main outcomes were waist circumference (WC), fasting plasma glucose (FPG), high-density lipids (HDL-c), triglycerides (Tg), and systolic (SBP) and diastolic (DBP) blood pressure, and secondary outcomes were body composition, anthropometric and physical fitness, determined before and after 20 weeks of concurrent training. NRs were defined as previously used technical error cut-off points for the MetS outcomes. Significantly different (all p < 0.05) prevalences of NRs between the H-MetS vs. L-MetS groups (respectively) in WC (NRs 18.2 % vs. 41.1 %, p < 0.0001), SBP (NRs 72.7 % vs. 47.0 %, p = 0.022), DBP (NRs 54.5 % vs. 76.4 %, p < 0.0001), FPG (NRs 100% vs. 64.8 %, p < 0.0001), and HDL-c (NRs 90.9 % vs. 64.7 %, p = 0.012) were observed. In addition, the H-MetS group evidenced significant changes on ΔSBP (−10.2 ± 11.4 mmHg), ΔFPG (−5.8 ± 8.2 mg/dl), ΔHDL-c (+4.0 ± 5.9 mg/dl), and ΔTg (−8.8 ± 33.8 mg/dl), all p < 0.05. The L-MetS group only showed significant changes in ΔWC (−3.8 ± 5.0 cm, p = 0.009). Comparing H-MetS vs. L-MetS groups, significant differences were observed in ∆FPG (−5.8 ± 8.2 vs. +0.3 ± 3.2 mg/dl, p = 0.027), but not in other MetS outcomes. In conclusion, 20 weeks of concurrent training promotes greater beneficial effects in morbidly obese patients with a high number of MetS risk factors. However, the NR prevalence for improving MetS outcomes was significantly superior in these more-diseased groups in SBP, FPG, and HDL-c, independent of their major training-induced effects.

Functional and Cardiovascular Measurements in Patients With Peripheral Artery Disease: COMPARISON BETWEEN MEN AND WOMEN

PURPOSE

To compare functional and cardiovascular variables of men and women with peripheral artery disease (PAD).

METHODS

This observational, cross-sectional study included 67 women and 144 men (age 66 ± 9 and 67 ± 10 yr, respectively) with PAD. Patients were submitted to a clinical evaluation, 6-min walk test (6MWT) and cardiovascular evaluation, including blood pressure, arterial stiffness variables, and heart rate variability.

RESULTS

Women had lower claudication onset distance (P = .033) and 6MWT distance (P < .001), and similar percentage of the predicted 6MWT distance (P > .05). Women had higher pulse pressure (P = .002), augmentation index (P < .001), augmentation index corrected by 75 bpm (P < .001), and brachial and central systolic blood pressure (P = .041 and P = .029). Diastolic blood pressure, pulse wave velocity, and heart rate variability were similar between sexes (P > .05).

CONCLUSION

Although predicted 6MWT performance was similar between sexes, women had higher blood pressure and wave reflection variables compared with men. Interventions to reduce blood pressure and wave reflection should be emphasized in women with PAD.

Effects of Exercise Mode on Arterial Stiffness in Symptomatic Peripheral Artery Disease Patients: A Randomized Crossover Clinical Trial

BACKGROUND

Exercise program has been recommended for the treatment of symptomatic peripheral artery disease (PAD) patients. However, whether exercise promotes reduction in arterial stiffness in these patients, who exhibit high arterial stiffness, is poor known.

AIM

To analyze the effects of a single session of resistance, walking, and combined exercises on arterial stiffness in symptomatic PAD patients and to describe individual responses and identify clinical predictors of arterial stiffness responses after exercises.

METHODS

Twelve patients with symptomatic PAD underwent four experimental sessions in random order: walking exercise (W - 10 bouts of 2-min walking at the speed corresponding to the onset of claudication pain with 2-min interval among sets), resistance exercise (R - 2 sets of 10 reps in eight resistance exercises), combined exercise (CO - 1 set of 10 reps in eight resistance exercises + 5 bouts of 2-min walking with 2-min interval between) and control session (C - resting in exercise room). Ambulatory arterial stiffness index (AASI) was obtained during ambulatory period after each session. Body mass index, ankle brachial index, sex and age also were evaluated.

RESULTS

AASI was lower in R compared to other sessions (R - 0.52 ± 0.05; W - 0.59 ± 0.05; CO - 0.64 ± 0.05; C - 0.60 ± 0.05, P < 0.001), with 75% of patients presenting lower AASI after R session. No difference was found between W, CO and C sessions (P> 0.05). Ankle brachial index was negatively correlated with R and W sessions net effect (r = -0.618 and -0.750, respectively; P< 0.05 for both), no correlation was found with CO.

CONCLUSION

A single bout of resistance exercise acutely reduces arterial stiffness in symptomatic PAD, while walking and combined exercise did not alter this variable. This response is more likely to occur in individuals with less severe disease.

Functional and Cardiovascular Parameters in Peripheral Artery Disease Patients with Interarm Blood Pressure Difference

BACKGROUND

To analyze the impact of interarm blood pressure difference (IAD) on functional and cardiovascular parameters in patients with peripheral artery disease (PAD).

METHODS

Ninety-eight patients with PAD were recruited in this cross-sectional study. Patients with differences between the right and left arms of systolic and/or diastolic blood pressure ≥10 mm Hg were classified as IAD, whereas the remaining patients were classified as PAD control subjects. Functional parameters included were the 6-min walk test, short physical performance battery, walking impairment questionnaire (WIQ), and the walking estimated-limitation calculated by history. Systemic cardiovascular parameters included were arterial stiffness and heart rate variability. Local cardiovascular parameters assessed in both arms were brachial blood pressure and flow-mediated dilation.

RESULTS

Patients with IAD presented higher systolic blood pressure and pulse pressure compared with control patients (P < 0.01). The carotid femoral pulse wave velocity tended to be higher and flow-mediated dilation tended to be lower in PAD patients with IAD compared with control subjects (P < 0.09). Patients with IAD presented lower scores in short physical performance battery (P = 0.012), WIQ distance (P = 0.003), WIQ speed (P = 0.008), WIQ stair climbing (P = 0.034), and walking estimated-limitation calculated by history (P = 0.026) when compared with PAD control patients.

CONCLUSIONS

In patients with PAD, IAD is associated with lower physical function and impairments in cardiovascular parameters compared with PAD patients without IAD.

Cardiac Autonomic Modulation Is Associated with Arterial Stiffness in Patients with Symptomatic Peripheral Artery Disease

BACKGROUND

The objective of this study was to analyze the association between cardiac autonomic modulation and arterial stiffness in patients with peripheral artery disease (PAD).

METHODS

This cross-sectional study included one hundred fourteen patients with symptomatic PAD (67.5% men; 65 ± 7 years; body mass index: 26.8 ± 4.5 kg/m²). Heart rate variability (HRV) was measured within time (standard deviation of all RR intervals [beat to beat heart interval] [SDNN], root mean square of the successive differences between adjacent normal RR intervals [RMSSD], and the proportion of successive RR intervals that differed by more than 50 msec [pNN50]) and frequency (low frequency [LF] and high frequency [HF]) domains. Arterial stiffness was assessed by carotid-femoral pulse wave velocity (cfPWV). Crude and adjusted linear regression analyses examined the relationship between HRV and cfPWV.

RESULTS

Nonsignificant crude associations were identified among cfPWV and RMSSD (P = 0.181), SDNN (P = 0.105), pNN50 (P = 0.087), LF (P = 0.376), HF (P = 0.175), and LF/HF ratio (P = 0.426). After adjustments for age, sex, smoking, body mass index, ankle-brachial index, and use of beta-blockers, significant associations were identified among cfPWV and RMSSD (P = 0.037), SDNN (P = 0.049), and pNN50 (P = 0.049).

CONCLUSIONS

Cardiac autonomic modulation was significantly associated with arterial stiffness in patients with PAD after adjustment for confounding factors. This relationship may contribute to the enhanced cardiovascular disease risk for PAD patients and provides a target for strategies to improve patient clinical outcomes.

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.

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.