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PURPOSE: Posttraumatic stress disorder (PTSD) has been associated with an increase in risk of cardiovascular disease (CVD). The goal of the study was to determine if peripheral vascular dysfunction, a precursor to CVD, was present in young adults with PTSD, and if an acute antioxidant (AO) supplementation could modify this potential PTSD-induced vascular dysfunction. METHODS: Thirteen individuals with PTSD were recruited for this investigation and were compared to 35 age- and sex-matched controls (CTRL). The PTSD group participated in two visits, consuming either a placebo (PTSD-PL) or antioxidants (PTSD-AO; Vitamins C and E; Alpha Lipoic Acid) prior to their visits, while the CRTL subjects only participated in one visit. Upper and lower limb vascular function were assessed via flow-mediated dilation and passive leg movement technique. Heart rate variability was utilized to assess autonomic nervous system modulation. RESULTS: The PTSD-PL condition, when compared to the CTRL group, reported lower arm and leg microvascular function as well as sympathetic nervous system (SNS) predominance. Following acute AO supplementation, arm, but not leg, microvascular function was improved and SNS predominance was lowered to which the prior difference between PTSD group and CTRL was no longer significant. CONCLUSION: Young individuals with PTSD demonstrated lower arm and leg microvascular function as well as greater SNS predominance when compared to age- and sex-matched controls. Furthermore, this lower vascular/autonomic function was augmented by an acute AO supplementation to the level of the healthy controls, potentially implicating oxidative stress as a contributor to this blunted vascular/autonomic function.

New Finding What is the central question of this study?This study sought to determine whether prior upper limb aerobic training can attenuate the vascular dysfunction resulting from negative alteration of blood flow patterns. What is the main finding and its importance?We demonstrated that the microvasculature of young men with prior upper limb aerobic training (rowing) was equally susceptible to negatively altered blood flow patterns when compared with untrained control subjects. This finding reveals that aerobic training does not provide adequate protection against this type of vascular insult, highlighting the importance of reducing known vascular insults regardless of training status. Abstract Acute alteration of blood flow patterns can substantially reduce blood vessel function and, if consistently repeated, may chronically reduce vascular health. Aerobic exercise training is associated with improved vascular health, but it is not well understood whether aerobic training‐induced vascular adaptations provide protection against acute vascular insults. This study sought to determine whether prior upper limb aerobic training can attenuate the vascular dysfunction resulting from an acute vascular insult (increased retrograde/oscillatory shear). Ten young arm‐trained (AT) men (rowers; 22 ± 1 years of age) and 10 untrained (UT) male control subjects (21 ± 3 years of age) were recruited for this study. Subjects completed two brachial artery (BA) flow‐mediated dilatation (FMD) tests separated by an acute bout of subdiastolic cuff inflation (SDCI) of the distal forearm. Brachial artery dilatation (normalized for the shear stimulus) and reactive hyperaemia evaluated during the BA FMD test were used to determine conduit artery and microvascular function, respectively. Data were presented as mean values ± SD. The AT group reported significantly greater whole body (peak oxygen uptake; P = 0.01) and forearm aerobic capacity (P < 0.001). The SDCI intervention significantly increased retrograde (P < 0.001) and oscillatory shear (P < 0.001) in both groups. After the SDCI, microvascular function (post‐cuff release hyperaemia), but not conduit artery function (shear‐induced BA dilatation), was significantly reduced from pre‐SDCI values (P = 0.001) independent of group. This study revealed that young men with prior upper limb aerobic training, when compared with untrained control subjects, were equally susceptible to the microvascular dysfunction associated with an acute increase in retrograde/oscillatory shear.

Vascular function and blood flow responses to upper limb exercise are differentially altered in response to different exercise training modalities. Rowing is a unique exercise modality that incorporates the upper limbs and can significantly augment upper limb endurance, strength, and power capacity. Purpose This study sought to determine whether vascular function and blood flow regulation during handgrip exercise are altered in row-trained males. Methods Nine young row-trained males (ROW, 20 ± 1 yr; V˙O2peak = 51 ± 2 mL·kg−1·min−1) and 14 recreationally active male controls (C: 22 ± 1 yr; V˙O2peak = 37 ± 2 mL·kg−1·min−1) were recruited for this study. Subjects performed multiple bouts of progressive rhythmic handgrip exercise. Brachial artery (BA) diameter, blood flow, shear rate, and mean arterial pressure were measured at rest and during the last minute of each exercise workload. Results Resting values for BA diameter, blood flow, shear rate, and mean arterial pressure were not different between groups. During handgrip exercise, the ROW group reported significantly lower BA blood flow (ROW vs C: 4 kg [146 ± 21 vs 243 ± 13 mL·min−1], 8 kg [248 ± 29 vs 375 ± 17 mL·min−1], 12 kg [352 ± 43 vs 490 ± 22 mL·min−1]) across all workloads when compared with controls. The examination of BA dilation, when controlled for the shear rate stimulus and evaluated across all workloads, was revealed to be significantly greater in ROW group versus controls. Conclusion This study revealed that vascular function and blood flow regulation were significantly different in row-trained males when compared with untrained controls evidenced by greater shear-induced BA dilation and lower arm blood flow during progressive handgrip exercise.

Purpose: Adequate, robust vascular responses to passive and active movement represent two distinct components linked to normal, healthy cardiovascular function. Currently, limited research exists determining if these vascular responses are altered in premenopausal females (PMF) when compared across sex or menstrual cycle phase. Methods: Vascular responses to passive leg movement (PLM) and handgrip (HG) exercise were assessed in PMF (n = 21) and age-matched men (n = 21). A subset of PMF subjects (n = 11) completed both assessments during the early and late follicular phase of their menstrual cycle. Microvascular function was assessed during PLM via changes in leg blood flow, and during HG exercise, via steady-state arm vascular conductance. Macrovascular (brachial artery [BA]) function was assessed during HG exercise via BA dilation responses as well as BA shear rate-dilation slopes. Results: Leg microvascular function, determined by PLM, was not different between sexes or across menstrual cycle phase. However, arm microvascular function, demonstrated by arm vascular conductance, was lower in PMF compared with men at rest and during HG exercise. Macrovascular function was not different between sexes or across menstrual cycle phase. Conclusions: This study identified similar vascular function across sex and menstrual cycle phase seen in microvasculature of the leg and macrovascular (BA) of the arm. Although arm microvascular function was unaltered by menstrual cycle phase in PMF, it was revealed to be significantly lower when compared with age-matched men highlighting a sex difference in vascular/blood flow regulation during small muscle mass exercise.