Vascular Responses to High-Intensity Battling Rope Exercise between the Sexes.

The purpose of the study was to assess high-intensity battling rope exercise (HI-BRE) on hemodynamics, pulse wave reflection and arterial stiffness during recovery and between sexes. Twenty-three young, healthy resistance-trained individuals (men: n = 13; women: n = 10) were assessed for all measures at Rest, as well as 10-, 30-, and 60-minutes following HI-BRE. A one-way repeated measures ANOVA was used to analyze the effects of HI-BRE across time (Rest, 10, 30, and 60-minutes) on all dependent variables. Significant main effects were analyzed using paired t-tests with a Sidak correction factor. Significance was accepted a priori at p 0.05. There were significant reductions in hemodynamic measures of diastolic blood pressure (BP) in women, but not men following HI-BRE at 30 minutes. Further, measures of pulse wave reflection, specifically those of the augmentation index (AIx) and wasted left ventricular energy (ΔEw), were significantly increased in both men and women for 60 minutes, but changes were significantly attenuated in women suggesting less ventricular work. There were also significant increases in arterial stiffness in regard to the aorta and common carotid artery that were fully recovered by 30 and 60 minutes, respectively with no differences between men and women. Thus, the primary findings of this study suggest that measures of hemodynamics and pulse wave reflection are collectively altered for at least 60 minutes following HI-BRE, with women having attenuated responses compared to men.

Autonomic modulation following an acute bout of bench press with and without blood flow restriction.

PURPOSE: Traditional resistance exercise decreases vagal tone up to 30 min after an acute bout of resistance exercise, which may increase the risk of cardiovascular events. However, the effects of resistance exercise with blood flow restriction (BFR) on autonomic modulation are unclear. To evaluate autonomic modulation after resistance exercise with and without BFR in resistance-trained men. METHODS: Eleven young men volunteered for the study. Autonomic modulation was assessed at rest, 15 (Rec 1), and 25 (Rec 2) minutes after low-load bench press with BFR (LL-BFR), traditional high-load bench press (HL), and a control (CON). Autonomic modulation assessments were expressed as natural logarithm (Ln), and included total power (LnTP), low-frequency power (LnLF), high-frequency power (LnHF), sympathovagal balance (LnLF/LnHF ratio), root mean square of the successive differences (LnRMSSD), and the proportion of intervals differing by > 50 ms from the preceding intervals (LnPNN50). A repeated measures ANOVA was used to evaluate conditions (LL-BFR, HL and CON) across time (Rest, Rec1, and Rec2) on autonomic modulation. RESULTS: There were significant condition by time interactions for LnTP, LnHF, and LnRMSSD such that they were reduced during recovery after LL-BFR and HL compared to Rest and CON. There were no interactions in the LnLF, LnLF/LnHF ratio, and LnPNN50. CONCLUSIONS: These data suggest that LL-BFR and HL significantly alter autonomic modulation up to 30 min after exercise with significant reduction after HL compared to LL-BFR when exercise volume is equated.

High-Intensity Interval Cycling Exercise on Wave Reflection and Pulse Wave Velocity.

Kingsley, JD, Tai, YL, Vaughan, J, and Mayo, X. High-intensity interval cycling exercise on wave reflection and pulse wave velocity. J Strength Cond Res 31(5): 1313-1320, 2017-The purpose of this study was to assess the effects of high-intensity exercise on wave reflection and aortic stiffness. Nine young, healthy men (mean ± SD: age: 22 ± 2 years) participated in the study. The high-intensity interval cycling exercise consisted of 3 sets of Wingate Anaerobic Tests (WATs) with 7.5% of bodyweight as resistance and 2 minutes of rest between each set. Measurements were taken at rest and 1 minute after completion of the WATs. Brachial and aortic blood pressures, as well as wave reflection characteristics, were measured through pulse wave analysis. Aortic stiffness was assessed through carotid-femoral pulse wave velocity (cfPWV). A repeated-measures analysis of variance was used to investigate the effects of the WATs on blood pressure and vascular function across time. There was no change in brachial or aortic systolic pressure from rest to recovery. There was a significant (p ≤ 0.05) decrease in brachial diastolic pressure (rest: 73 ± 6 mm Hg; recovery: 67 ± 9 mm Hg) and aortic diastolic pressure (rest: 75 ± 6 mm Hg; recovery: 70 ± 9 mm Hg) from rest to recovery. In addition, there was no significant change in the augmentation index (rest: 111.4 ± 6.5%; recovery: 109.8 ± 5.8%, p = 0.65) from rest to recovery. However, there was a significant (p ≤ 0.05) increase in the augmentation index normalized at 75 b·min (rest: 3.29 ± 9.82; recovery 21.21 ± 10.87) during recovery compared with rest. There was no change in cfPWV (rest: 5.3 ± 0.8 m·s; recovery: 5.7 ± 0.5m·s; p = 0.09) in response to the WAT. These data demonstrate that high-intensity interval cycling exercise with short rest periods has a nonsignificant effect on vascular function.

[Living With Tolerable Burden: Exploring the Ethical Self of Nurses Who Provide End-of-Life Care].

BACKGROUND: Providing end-of-life (EOL) care elicits complex emotions in nurses in the context of modern medicine. Nurses must not only watch their patients succumb to disease and death but also witness their suffering. PURPOSE: This qualitative study adopted the perspective of "the other", as proposed by Emmanuel Levinas, to understand the experience of nurses who provide EOL care and the possibilities of nurses build up their ethical selves within the context of modern medicine. METHODS: The study used interpretative phenomenology and group dialogue. Thirteen nurses who had EOL care experience were included. Data were drawn from the six transcripts of the group sessions, the researcher's diaries, and participants' feedback sheets. Interpretative phenomenological analysis was used to analyze the data. RESULTS: The findings showed that nurses not only execute medical procedures but are also capable of self-molding into ethical subjects. The categories of participant experiences included: (1) encountering the death; (2) encountering my inner self; and (3) greeting the death. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: EOL nursing does not require abstract or decontextualized knowledge, but rather requires more experiential knowledge. EOL care may inspire nurses to become ethical persons and to gain wisdom if they shift away from a self-centered perspective to receive "the other". This study illustrates that EOL care should not depend solely on ethical codes or principles but should also adopt the attitudes of "for the other".

Arterial Stiffness and Autonomic Modulation After Free-Weight Resistance Exercises in Resistance Trained Individuals.

Kingsley, JD, Mayo, X, Tai, YL, and Fennell, C. Arterial stiffness and autonomic modulation after free-weight resistance exercises in resistance trained individuals. J Strength Cond Res 30(12): 3373-3380, 2016-We investigated the effects of an acute bout of free-weight, whole-body resistance exercise consisting of the squat, bench press, and deadlift on arterial stiffness and cardiac autonomic modulation in 16 (aged 23 ± 3 years; mean ± SD) resistance-trained individuals. Arterial stiffness, autonomic modulation, and baroreflex sensitivity (BRS) were assessed at rest and after 3 sets of 10 repetitions at 75% 1-repetition maximum on each exercise with 2 minutes of rest between sets and exercises. Arterial stiffness was analyzed using carotid-femoral pulse wave velocity (cf-PWV). Linear heart rate variability (log transformed [ln] absolute and normalized units [nu] of low-frequency [LF] and high-frequency [HF] power) and nonlinear heart rate complexity (Sample Entropy [SampEn], Lempel-Ziv Entropy [LZEn]) were measured to determine autonomic modulation. BRS was measured by the sequence method. A 2 × 2 repeated measures analysis of variance (ANOVA) was used to analyze time (rest, recovery) across condition (acute resistance exercise, control). There were significant increases in cf-PWV (p = 0.05), heart rate (p = 0.0001), normalized LF (LFnu; p = 0.001), and the LF/HF ratio (p = 0.0001). Interactions were also noted for ln HF (p = 0.006), HFnu (p = 0.0001), SampEn (p = 0.001), LZEn (p = 0.005), and BRS (p = 0.0001) such that they significantly decreased during recovery from the resistance exercise compared with rest and the control. There was no effect on ln total power, or ln LF. These data suggest that a bout of resistance exercise using free-weights increases arterial stiffness and reduces vagal activity and BRS in comparison with a control session. Vagal tone may not be fully recovered up to 30 minutes after a resistance exercise bout.

Hemodynamics and Arterial Stiffness in Response to Oral Glucose Loading in Individuals with Type II Diabetes and Controlled Hypertension.

INTRODUCTION: Type 2 diabetes (T2D), the fastest growing pandemic, is typically accompanied by vascular complications. A central hallmark of both T2D and vascular disease is insulin resistance which causes impaired glucose transport and vasoconstriction concomitantly. Those with cardiometabolic disease display greater variation in central hemodynamics and arterial elasticity, both potent predictors of cardiovascular morbidity and mortality, which may be exacerbated by concomitant hyperglycemia and hyperinsulinemia during glucose testing. Thus, elucidating central and arterial responses to glucose testing in those with T2D may identify acute vascular pathophysiologies triggered by oral glucose loading. AIM: This study compared hemodynamics and arterial stiffness to an oral glucose challenge (OGC: 50g glucose) between individuals with and without T2D. 21 healthy (48 ± 10 years) and 20 participants with clinically diagnosed T2D and controlled hypertension (52 ± 8 years) were tested. METHODS: Hemodynamics and arterial compliance were assessed at baseline, and 10, 20, 30, 40, 50, and 60 min post-OGC. RESULTS: Heart rate increased between 20 and 60 post-OGC in both groups (p < 0.05). Central systolic blood pressure (SBP) decreased in the T2D group between 10 and 50 min post-OGC while central diastolic blood pressure (DBP) decreased in both groups from 20 to 60 post-OGC. Central SBP decreased in T2D between 10 and 50 min post-OGC and central DBP decreased in both groups between 20 and 60 min post-OGC. Brachial SBP decreased between 10 and 50 min in healthy participants, whereas both groups displayed decreases in brachial DBP between 20 and 60 min post-OGC. Arterial stiffness was unaffected. CONCLUSIONS: An OGC alters central and peripheral blood pressure in healthy and T2D participants similarly with no changes in arterial stiffness.

Hemodynamic response and pulse wave analysis after upper- and lower-body resistance exercise with and without blood flow restriction.

Resistance exercise (RE) has been shown to elevate hemodynamics and pulse wave reflection. However, the effects of acute RE with blood flow restriction (BFR) on hemodynamics and pulse wave reflection are unclear. The purpose of this study was to evaluate the differences between upper- and lower-body RE with and without BFR on hemodynamics and pulse wave reflection. Twenty-three young resistance-trained individuals volunteered for the study. Hemodynamics and pulse wave reflection were assessed at rest, 10, 25, 40, and 55 min after either upper- or lower-body with or without BFR. The upper-body RE (URE) consisted of the latissimus dorsi pulldown and chest press; the lower-body RE (LRE) consisted of knee extension and knee flexion. The BFR condition consisted of four sets of 30, 15, 15, and 15 repetitions at 30% 1-repetition maximum (1RM) while the without BFR condition consisted of four sets of 8 repetitions at 70% 1RM. Heart rate, rate pressure product, and subendocardial viability ratio significantly (p < 0.05) increased after all exercises. Brachial and aortic systolic blood pressure (BP) significantly (p < 0.05) elevated after LRE while brachial and aortic diastolic BP significantly (p < 0.05) reduced after URE. Augmentation pressure, augmentation index (AIx), AIx normalized at 75 bpm, and wasted left ventricular pressure energy significantly (p < 0.05) increased after URE while transit time of reflected wave significantly (p < 0.05) decreased after LRE. URE places greater stress on pulse wave reflection while LRE results in greater responses in BP. Regardless of URE or LRE, the cardiovascular responses between BFR and without BFR are similar.HIGHLIGHTS High-load resistance exercise and low-load resistance exercise with blood flow restriction may produce similar cardiovascular responses.Upper-body resistance exercise generates greater changes on pulse wave reflections while lower-body resistance exercise induces greater elevations in systolic blood pressure.

The Effects of Machine-Weight and Free-Weight Resistance Exercise on Hemodynamics and Vascular Function.

The purpose of this study was to examine hemodynamic and vascular responses between machine-weight and free-weight exercise. Resistance-trained individuals were assigned to a machine-weight (n = 13) or free-weight (n = 15) group. Groups completed two visits consisting of their assigned exercise condition and a control (CON). A 2 × 2 × 3 repeated measures ANOVA was used to test the effects of group across condition and time on the hemodynamic parameters [cardiac output (CO), heart rate (HR), total peripheral resistance (TPR), mean arterial pressure (MAP), and stroke volume (SV)]. A 2 × 2 × 2 repeated measures ANOVA was used to test the effects of group across condition and time on the hemodynamic variable, forearm vascular conductance (FVC), as well as on vascular measures [forearm blood flow (FBF), blood flow peak, and total reactive hyperemia (RH)]. Main effects were analyzed using pairwise comparisons. The results of the present study demonstrate that both machine-weight and free-weight exercise produce similar (p > 0.05) alterations in hemodynamics and vascular function. Specifically, during recovery both groups demonstrated significant (p ≤ 0.05) increases in measures of hemodynamics such as CO, HR and FVC, as well as significant (p ≤ 0.05) decreases in TPR, MAP, and SV. Measures of vascular function such as FBF, blood flow peak, and total RH were also significantly (p ≤ 0.05) increased during recovery. Therefore, this study suggests that either machine weight or free-weight exercise may induce acute hemodynamic and vascular benefits, which may reduce the risk of cardiovascular disease (CVD) and CVD events.

Free-weight versus weight machine resistance exercise on pulse wave reflection and aortic stiffness in resistance-trained individuals.

The purpose of this study was to compare the vascular responses to acute free-weight (FW) resistance exercise (RE) versus weight machines (WM). Thirty-two resistance-trained individuals participated in this study. Both modalities involved performing acute RE and a control. Blood pressure and measures of pulse wave reflection were assessed using pulse wave analysis. Aortic stiffness was assessed using carotid-femoral pulse wave velocity (cf-PWV). A repeated measures analysis of variance was used to determine the effects of modality (FW and WM) and condition (acute RE and control) across time (rest and 10-20 min after exercise) on measures of pulse wave reflection and aortic stiffness. Significance was set a priori at p ≤ 0.05. There were no modality by condition by time interactions for any variable, such that the FW and WM modalities responded similarly across time after acute RE (p > 0.05). There were significant (p ≤ 0.05) increases in heart rate, aortic systolic blood pressure, aortic pulse pressure, augmentation index normalized at 75bpm, and decreases in subendocardial viability ratio (SEVR) after acute RE, compared to rest. There was also a significant (p ≤ 0.05) increase in cf-PWV after acute RE, compared to rest. In conclusion, this study demonstrates that acute free-weight and weight-machine RE are associated with transient increases in measures of pulse wave reflection and aortic stiffness, with reductions in myocardial perfusion. These data demonstrate that both modalities result in significant stress on the myocardium during recovery, while simultaneously increasing pressure on the aorta for at least 10-20 min.

Pulse wave reflection responses to bench press with and without practical blood flow restriction.

Resistance exercise is recommended to increase muscular strength but may also increase pulse wave reflection. The effect of resistance exercise combined with practical blood flow restriction (pBFR) on pulse wave reflection is unknown. The purpose of this study was to evaluate the differences in pulse wave reflection characteristics between bench press with pBFR and traditional high-load bench press in resistance-trained men. Sixteen resistance-trained men participated in the study. Pulse wave reflection characteristics were assessed before and after low-load bench press with pBFR (LL-pBFR), traditional high-load bench press (HL), and a control (CON). A repeated-measures ANOVA was used to evaluate differences in pulse wave reflection characteristics among the conditions across time. There were significant (p ≤ 0.05) interactions for heart rate, augmentation index, augmentation index normalized at 75 bpm, augmentation pressure, time-tension index, and wasted left ventricular energy such that they were increased after LL-pBFR and HL compared with rest and CON, with no differences between LL-pBFR and HL. Aortic pulse pressure (p < 0.001) was elevated only after LL-pBFR compared with rest. In addition, there was a significant (p ≤ 0.05) interaction for aortic diastolic blood pressure (BP) such that it was decreased after LL-pBFR compared with rest and CON but not HL. The subendocardial viability ratio and diastolic pressure-time index were significantly different between LL-pBFR and HL compared with rest and CON. There were no significant interactions for brachial systolic or diastolic BP, aortic systolic BP, or time of the reflected wave. In conclusion, acute bench press resistance exercise significantly altered pulse wave reflection characteristics without differences between LL-pBFR and HL.

Autonomic modulation and baroreflex sensitivity after acute resistance exercise: responses between sexes.

BACKGROUND: The aim of this study was to evaluate autonomic modulation, blood pressure variability and baroreflex sensitivity (BRS) responses to an acute bout of free-weight resistance exercise in resistance-trained men (N.=14) and women (N.=13). METHODS: Participants underwent both an acute bout of resistance exercise (RE) consisting of 3 sets of 10 repetitions at 75% 1-repetition maximum on the squat, bench press, and deadlift, and a quiet control. Autonomic modulation, blood pressure variability (LFSAP), and cardiovagal BRS were assessed at rest, 15-20 minutes (Rec1) and 25-30 minutes (Rec2) postexercise. Log transformed measures of autonomic modulation included root square of the mean ssquared differences of successive RR intervals (LnRMSSD), high-frequency power (LnHFRR) and low-frequency power (LnLFRR) and sympathovagal balance (LnLFRR/HFRR). LFSAP was used as a measurement of vasomotor tone. Cardiovagal BRS was assessed using the sequence method. RESULTS: There were no significant sex differences at rest and no significant sex by time by condition interactions for any variable. Compared with rest there were augmentations in LnLFRR/HFRR (P=0.002) and LFSAP (P=0.001) at Rec1 and Rec2. RMSSD and cardiovagal BRS were significantly (P=0.0001) decreased at Rec1 and Rec2 compared to rest after the acute RE. CONCLUSIONS: Both sexes demonstrated that acute resistance exercise using free weights has a profound impact on autonomic modulation, blood pressure variability and cardiovagal BRS.

Acute resistance exercise using free weights on aortic wave reflection characteristics.

Aortic wave reflection characteristics such as the augmentation index (AIx), wasted left ventricular pressure energy (ΔEw ) and aortic haemodynamics, such as aortic systolic blood pressure (ASBP), strongly predict cardiovascular events. The effects of acute resistance exercise (ARE) using free-weight exercises on these characteristics are unknown. Therefore, we sought to determine the effects of acute free-weight resistance exercise on aortic wave reflection characteristics and aortic haemodynamics in resistance-trained individuals. Fifteen young, healthy resistance-trained (9 ± 3 years) individuals performed two randomized sessions consisting of an acute bout of free-weight resistance exercise (ARE) or a quiet control (CON). The ARE consisted of three sets of 10 repetitions at 75% one repetition maximum for squat, bench press and deadlift. In CON, the participants rested in the supine position for 30 min. Measurements were made at baseline before sessions and 10 min after sessions. A two-way ANOVA was used to compare the effects of condition across time. There were no significant interactions for aortic or brachial blood pressures. Compared to rest, there were significant increases in augmentation pressure (rest: 5·7 ± 3·0 mmHg; recovery: 10·4 ± 5·7 mmHg, P = 0·002), AIx (rest: 116·8 ± 4·2%; recovery: 123·2 ± 8·4%, P = 0·002), AIx normalized at 75 bpm (rest: 5·2 ± 7·6%; recovery: 27·3 ± 13·2%, P<0·0001), ΔEw (rest: 1215 ± 674 dynes s cm-2 ; recovery: 2096 ± 1182 dynes s cm-2 , P = 0·008), and there was a significant decrease in transit time of the reflected wave (rest: 150·7 ± 5·8 ms; recovery 145·5 ± 5·6 ms, P<0·001) during recovery from ARE compared to CON. These data suggest that ARE using free-weight exercises may have no effect on aortic and brachial blood pressure but may significantly alter aortic wave reflection characteristics.

Autonomic Modulation in Older Women: Using Resistance Exercise as a Countermeasure.

It is unclear if resistance training (RT) can be used to alter declines in autonomic modulation associated with aging. Young women (YW; range 18-25 yrs) and older women (OW; range 50-72 yrs) were compared at baseline. Only OW underwent supervised RT 2 days a week for 12-weeks. Baseline and post-training measurements included heart rate variability (HRV) and complexity (Sample Entropy) to assess autonomic modulation. The 12-weeks of RT consisted of 9 exercises performing 3 sets of 8-12 repetitions. At baseline, group differences in maximal strength, and autonomic modulation were evaluated with a one-way ANOVA with BMI as a covariate. In the OW, the effects of RT were evaluated with repeated-measures ANOVA in order to compare baseline to after RT. The YW had significantly (p≤0.05) lower diastolic, but not systolic blood pressure. The YW also had significantly (p≤0.05) greater absolute Ln (natural logarithm) high-frequency (HF) power and normalized HF power compared to the OW. In addition, there were significantly (p≤0.05) greater levels of normalized low-frequency power (LF) (and the LF/HF ratio) in the OW compared to the YW before RT. However, no difference was found for Sample Entropy. After RT, OW significantly (p≤0.05) increased the chest press (28%) and leg extension (33%). RT had no significant effect on any autonomic parameter suggesting that it may not be a sufficient stimulus to alter the effects of aging.

Free-weight resistance exercise on pulse wave reflection and arterial stiffness between sexes in young, resistance-trained adults.

We sought to determine the sex-specific effects of an acute bout of free-weight resistance exercise (RE) on pulse wave reflection (aortic blood pressures, augmentation index (AIx), AIx at 75 bpm (AIx@75), augmentation pressure (AP), time of the reflected wave (Tr), subendocardial viability ratio (SEVR)), and aortic arterial stiffness in resistance-trained individuals. Resistance-trained men (n = 14) and women (n = 12) volunteered to participate in the study. Measurements were taken in the supine position at rest, and 10 minutes after 3 sets of 10 repetitions at 75% 1-repetition maximum on the squat, bench press, and deadlift. A 2 × 2 × 2 ANOVA was used to analyse the effects of sex (men, women) across condition (RE, control) and time (rest, recovery). There were no differences between sexes across conditions and time. There was no effect of the RE on brachial or aortic blood pressures. There were significant condition × time interactions for AIx (rest: 12.1 ± 7.9%; recovery: 19.9 ± 10.5%, p = .003), AIx@75 (rest: 5.3 ± 7.9%; recovery: 24.5 ± 14.3%, p = .0001), AP (rest: 4.9 ± 2.8 mmHg; recovery: 8.3 ± 6.0 mmHg, p = .004), and aortic arterial stiffness (rest: 5.3 ± 0.6 ms; recovery: 5.9 ± 0.7 ms, p = .02) with significant increases during recovery from the acute RE. There was also a significant condition × time for time of the reflected wave (rest: 150 ± 7 ms; recovery: 147 ± 9 ms, p = .02) and SEVR (rest: 147 ± 17%; recovery: 83 ± 24%, p = .0001) such that they were reduced during recovery from the acute RE compared to the control. These data suggest that an acute bout of RE increases AIx, AIx@75, and aortic arterial stiffness similarly between men and women without significantly altering aortic blood pressures.