Publications by authors named "Blake Perry"

Background And Aim: Dysmenorrhea affects the majority of young women worldwide, but geographical and cultural differences can influence the reporting, impact and management of symptoms. Aotearoa New Zealand is a culturally diverse country, with a high proportion of Māori and Pacific peoples. The aim of this scoping review was to assess the current literature on the prevalence, impact and management strategies for dysmenorrhea in Aotearoa New Zealand.

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Dynamic resistance exercise (RE) produces sinusoidal fluctuations in blood pressure, with hypotension and cerebral hypoperfusion commonly observed immediately following RE. Whether the cerebral vasculature adapts to these regular blood pressure challenges is unclear. This study examined the cerebrovascular response to post-dynamic RE orthostasis.

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During unilateral static and rhythmic handgrip exercise, middle cerebral artery blood velocity (MCAv) increases in the contralateral side to the exercising limb. However, whether this neurovascular coupling-mediated increase in contralateral MCAv is apparent against a background of fluctuating perfusion pressure produced by dynamic resistance exercise (RE) is unclear. We examined the cerebral haemodynamic response to unilateral dynamic RE in 30 healthy individuals (female = 16, mean ± SD: age, 26 ± 6 years; height, 175 ± 10 cm; weight, 74 ± 15 kg; body mass index, 24 ± 5 kg m).

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To determine whether using nicotine exacerbates exertional heat strain through an increased metabolic heat production (H) or decreased skin blood flow (SkBF), 10 nicotine-naïve trained males [37 ± 12 yr; peak oxygen consumption (V̇o): 66 ± 10 mL·min·kg] completed four trials at 20°C and 30°C following overnight transdermal nicotine (7 mg·24 h) and placebo use in a crossover, double-blind design. They cycled for 60 min (55% V̇o) followed by a time trial (∼75% V̇o) during which measures of gastrointestinal (T) and mean weighted skin ([Formula: see text]) temperatures, SkBF, H, and mean arterial pressure (MAP) were made. The difference in ΔT between nicotine and placebo trials was greater during 30°C (0.

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Dynamic resistance exercise (RE) produces sinusoidal fluctuations in blood pressure with simultaneous fluctuations in middle cerebral artery blood velocity (MCAv). Some evidence indicates that RE may alter cerebrovascular function. This study aimed to examine the effects of habitual RE training on the within-RE cerebrovascular responses.

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Article Synopsis
  • The study investigates how different intensities of exercise affect post-exercise hypotension, focusing on critical power and the gas exchange threshold as metabolic benchmarks.
  • It hypothesizes that exercising above critical power will lead to a greater decrease in blood pressure after exercise compared to exercising below it.
  • Results indicate that post-exercise hypotension is significantly more pronounced after workouts 10% above critical power, demonstrating the critical power threshold's importance in influencing blood pressure recovery.
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Background: During hyperthermia, the perturbations in mean arterial blood pressure (MAP) produced by the Valsalva manoeuvre (VM) are more severe. However, whether these more severe VM-induced changes in MAP are translated to the cerebral circulation during hyperthermia is unclear.

Methods: Healthy participants (n = 12, 1 female, mean ± SD: age 24 ± 3 years) completed a 30 mmHg (mouth pressure) VM for 15 s whilst supine during normothermia and mild hyperthermia.

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There is emerging evidence that ovarian hormones play a significant role in the lower stroke incidence observed in pre-menopausal women compared with men. However, the role of ovarian hormones in cerebrovascular regulation remains to be elucidated. We examined the blood pressure-cerebral blood flow relationship (cerebral autoregulation) across the menstrual cycle in eumenorrheic women (n = 12; mean ± SD: age, 31 ± 7 years).

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New Findings: What is the central question of this study? Does habitual exercise modality affect the directionality of the cerebral pressure-flow relationship? What is the main finding and its importance? These data suggest the hysteresis-like pattern of dynamic cerebral autoregulation appears present in long-term sedentary and endurance-trained individuals, but absent in resistance-trained individuals. This is the first study to expand knowledge on the directional sensitivity of the cerebral pressure-flow relationship to trained populations.

Abstract: Evidence suggests the cerebrovasculature may be more efficient at dampening cerebral blood flow (CBF) variations when mean arterial pressure (MAP) transiently increases, compared to when it decreases.

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Resistance exercise (RE) is a popular modality for the general population and athletes alike, due to the numerous benefits of regular participation. The acute response to dynamic RE is characterised by temporary and bidirectional physiological extremes, not typically seen in continuous aerobic exercise (e.g.

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Background: Offspring of parent(s) with age-related macular degeneration (AMD) have a 45% lifetime risk of developing the disease. High foveal macular pigment optical density (MPOD) is protective, whereas individuals with a "foveal macular pigment dip" (FMPD) are at increased risk. Shortage of the dietary carotenoids lutein, zeaxanthin as well as fish consumption are reported AMD risk factors.

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Hyperthermia produces profound redistribution of blood and circulatory reflex function. We investigated the potential for lower body positive pressure (LBPP) to maintain or restore haemodynamics during graded hyperthermia. Eight healthy adults rested supine in a custom-made LBPP box, sealed distal to the iliac crest.

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Sports-related concussions pose a significant public health concern, and preventative measures are needed to help reduce risk in sport. Vision training could be a suitable prevention strategy for sports-related concussion to help improve athletes' abilities to scan the visual field for oncoming objects or opponents and thus anticipate head impacts. By accurately anticipating impacts, athletes can prepare for impact or attempt to avoid the collision altogether.

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We examined the acute effects of anthocyanin-rich New Zealand blackcurrant extract and a placebo on hemodynamics during 120 min of sedentary sitting in healthy males. Additionally, we investigated whether changes in resting hemodynamics altered repeated isometric hand-grip exercise performance and post exercise forearm blood flow (FBF). Ten healthy males completed two trials during which they ingested either blackcurrant extract (1.

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Purpose: To examine the interactive effects of VM and isometric resistance exercise on cerebral haemodynamics.

Methods: Eleven healthy participants (mean ± SD 28 ± 9 years; 2 females) completed 20-s bilateral isometric leg extension at 50% of maximal voluntary contraction with continued ventilation (RE), a 20-s VM at mouth pressure of 40 mmHg (VM), and a combination (RE + VM), in randomised order. Mean beat-to-beat blood velocity in the posterior (PCAv) and middle cerebral arteries (MCAv), vertebral artery blood flow, end-tidal partial pressure of CO and mean arterial pressure (MAP) were measured.

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Purpose: To evaluate the ability of preoperative phenylephrine testing to predict postoperative upper eyelid tarsal platform show in patients undergoing Müller muscle-conjunctival resection (MMCR) ptosis repair without concurrent blepharoplasty.

Methods: A retrospective chart review was performed on 52 eyelids of patients who underwent MMCR without external skin incision. Photographs were reviewed to objectively and subjectively compare the results of phenylephrine testing to postoperative appearance.

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New Findings: What is the central question of this study? Does habitual resistance and endurance exercise modify dynamic cerebral autoregulation? What is the main finding and its importance? To the authors' knowledge, this is the first study to directly assess dynamic cerebral autoregulation in resistance-trained individuals, and potential differences between exercise training modalities. Forced oscillations in blood pressure were induced by repeated squat-stands, from which dynamic cerebral autoregulation was assessed using transfer function analysis. These data indicate that dynamic cerebral autoregulatory function is largely unaffected by habitual exercise type, and further document the systemic circulatory effects of regular exercise.

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Key Points: One in two female athletes chronically take a combined, monophasic oral contraceptive pill (OCP). Previous thermoregulatory investigations proposed that an endogenous rhythm of the menstrual cycle still occurs with OCP usage. Forthcoming large international sporting events will expose female athletes to hot environments differing in their thermal profile, yet few data exist on how trained women will respond from both a thermoregulatory and performance stand-point.

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Purpose: The purpose of this study was to identify whether post-resistance exercise (REx) blood flow restriction (BFR) can elicit a similar acute training stimulus to that offered by either heavy REx or traditional low-load BFR REx.

Method: Ten men completed trials with 30% one-repetition maximum (1RM) for 5 sets of 15 repetitions without BFR (30%), with BFR during exercise (30% RD), and with postexercise BFR (30% RP) and at 75% 1RM for 3 sets of 10 repetitions. Lactate and cortisol were measured before and up to 60 min after exercise.

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Conjunctivodacryocystorhinostomy with placement of a Jones tube (JT) is the gold standard for upper lacrimal system dysfunction. However, traditional JT have been associated with various complications. In their practice, the authors have encountered challenges with postoperative dry eye in a select group of patients, with recurrence of epiphora following tube occlusion, suggesting a need for decreasing the rate of tear drainage while maintaining a patent JT.

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Real-world cycling performance depends not only on exercise capacities, but also on efficiently traversing the bicycle through the terrain. The aim of this study was to determine if it was possible to quantify the braking done by a cyclist in the field. One cyclist performed 408 braking trials (348 on a flat road; 60 on a flat dirt path) over 5 days on a bicycle fitted with brake torque and angular velocity sensors to measure brake power.

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Purpose: To describe success rates and long-term outcomes of conjunctivodacryocystorhinostomy (CDCR) with larger collar (4.5 or 5.0 mm) frosted Jones tubes (FJTs).

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Key Points: Despite an attenuated fluctuation in ovarian hormone concentrations in well-trained women, one in two of such women believe their menstrual cycle negatively impacts training and performance. Forthcoming large international events will expose female athletes to hot environments, and studies evaluating aerobic exercise performance in such environments across the menstrual cycle are sparse, with mixed findings. We have identified that autonomic heat loss responses at rest and during fixed-intensity exercise in well-trained women are not affected by menstrual cycle phase, but differ between dry and humid heat.

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Introduction: Repair of large defects of the lower eyelid can be difficult. A common procedure performed to address these defects is a Hughes flap. This procedure has a number of disadvantages: The eye is closed postoperatively, a second stage is required, and the edge of the flap is often erythematous.

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