Using environmental and exercise physiology to address gender inequalities in climate change and occupational health research.

Climate change is a health-risk and health-inequity multiplier with excessive heat exposure a direct climate change impact already affecting the health and livelihood of billions globally. Women face greater risks and burdens from climate change impacts. Biological sex may or may not influence an individual's thermoregulatory capacity, heat tolerance or heat susceptibility.

The Environmental Impact of a High-Altitude Medical Research Expedition.

Joyce, Kelsey E., Catherine A. Campbell, Arthur R.

The work-recovery cycle of kidney strain and inflammation in sugarcane workers following repeat heat exposure at work and at home.

Purpose: To examine heat exposure at work and home and the work-recovery cycle and temporal variation of kidney strain, muscle injury and inflammation biomarkers in sugarcane workers.

Methods: 20 male sugarcane workers (age: 33 ± 7 years) with a workplace Rest.Shade.

Nocturnal pulse oximetry for the detection and prediction of acute mountain sickness: An observational study.

Acute mountain sickness (AMS) is a well-studied illness defined by clinical features (e.g., headache and nausea), as assessed by the Lake Louise score (LLS).

Association Between Acute Kidney Injury Hospital Visits and Environmental Heat Stress at a Nicaraguan Sugarcane Plantation.

Background: Mesoamerican sugarcane cutters are at a high risk of chronic kidney disease of non-traditional origin, a disease likely linked to heat-related acute kidney injury (AKI). Studies in general populations have described a positive association between high environmental temperatures and clinically assessed kidney outcomes, but there are no studies in occupational settings.

Method: We accessed routine records of clinically diagnosed AKI (AKI-CD) and wet bulb globe temperatures (WBGT) at a large Nicaraguan sugarcane plantation and modeled the relationship between these using negative binomial regression.

Impact of heat and a rest-shade-hydration intervention program on productivity of piece-paid industrial agricultural workers at risk of chronic kidney disease of nontraditional origin.

Objectives: Assess the impact of environmental heat and a rest-shade-hydration (RSH) intervention against heat stress on productivity of piece-paid Mesoamerican sugarcane cutters. These workers are at a high risk of chronic kidney disease of non-traditional origin (CKDnt), from the severe heat stress they experience due to heavy work under hot conditions. RSH interventions in these populations improve kidney health outcomes, but their impact on productivity has yet to be examined.

Exposure to passive heat and cold stress differentially modulates cerebrovascular-CO responsiveness.

Heat and cold stress influence cerebral blood flow (CBF) regulatory factors (e.g., arterial CO partial pressure).

Menstrual phase influences cerebrovascular responsiveness in females but may not affect sex differences.

Sex differences in the rate and occurrence of cerebrovascular diseases (e.g., stroke) indicate a role for female sex hormones (i.

Targeting workload to ameliorate risk of heat stress in industrial sugarcane workers.

Objective: The aim of this study was to quantify the physiological workload of manual laborers in industrial sugarcane and assess the effect of receiving a rest, shade, and hydration intervention to reduce heat stress exposure risk.

Methods: In an observational study, physiological workload was evaluated for burned cane cutters (BCC), seed cutters (SC) and drip irrigation repair workers (DIRW) using heart rate (HR) recorded continuously (Polar®) across a work shift. Workers' percentage of maximal HR (%HR), time spent in different HR zones, and estimated core temperature (ECTemp) were calculated.

Non-pharmacological interventions for vascular health and the role of the endothelium.

The most common non-pharmacological intervention for both peripheral and cerebral vascular health is regular physical activity (e.g., exercise training), which improves function across a range of exercise intensities and modalities.

Impact of acute dynamic exercise and arterial shear rate modification on radial artery low-flow mediated constriction in young men.

Purpose: Leg cycling exercise acutely augments radial artery low-flow mediated constriction (L-FMC). Herein, we sought to determine whether this is associated with exercise-induced changes in arterial shear rate (SR).

Methods: Ten healthy and recreationally active young men (23 ± 2 years) participated in 30 min of incremental leg cycling exercise (50, 100, 150 Watts).

Workplace Intervention for Heat Stress: Essential Elements of Design, Implementation, and Assessment.

Heat stress is associated with numerous health effects that potentially harm workers, especially in a warming world. This investigation occurred in a setting where laborers are confronted with occupational heat stress from physically demanding work in high environmental temperatures. Collaboration with a major Nicaraguan sugarcane producer offered the opportunity to study interventions to prevent occupational heat-stress-related kidney disease.

Sex differences in adaptation to intermittent post-exercise sauna bathing in trained middle-distance runners.

Background: The purpose of this study was to investigate the effect of sex on the efficacy of intermittent post-exercise sauna bathing to induce heat acclimation and improve markers of temperate exercise performance in trained athletes.

Methods: Twenty-six trained runners (16 female; mean ± SD, age 19 ± 1 years, V̇O F: 52.6 ± 6.

A Systematic Review and Meta-Analysis Examining Whether Changing Ovarian Sex Steroid Hormone Levels Influence Cerebrovascular Function.

Sex differences in cerebrovascular disease rates indicate a possible role for ovarian sex steroid hormones in cerebrovascular function. To synthesise and identify knowledge gaps, a systematic review and meta-analysis was conducted to assess how ovarian sex steroid hormone changes across the lifespan affect cerebrovascular function in women. Three databases (EMBASE, MEDLINE and Web of Science) were systematically searched for studies on adult cerebrovascular function and ovarian sex steroid hormones.

Occupational heat exposure and the risk of chronic kidney disease of nontraditional origin in the United States.

Occupational heat exposure is linked to the development of kidney injury and disease in individuals who frequently perform physically demanding work in the heat. For instance, in Central America, an epidemic of chronic kidney disease of nontraditional origin (CKDnt) is occurring among manual laborers, whereas potentially related epidemics have emerged in India and Sri Lanka. There is growing concern that workers in the United States suffer with CKDnt, but reports are limited.

Corrigendum: Cerebral Hemodynamic and Neurotrophic Factor Responses Are Dependent on the Type of Exercise.

[This corrects the article DOI: 10.3389/fphys.2020.

Cerebral Hemodynamic and Neurotrophic Factor Responses Are Dependent on the Type of Exercise.

This study examined acute cerebral hemodynamic and circulating neurotrophic factor responses to moderate intensity continuous exercise (MICT), guideline-based high intensity interval exercise (HIIT), and sprint interval exercise (SIT). We hypothesized that the pattern of middle cerebral artery velocity (MCAv) response would differ between interval and continuous exercise, with SIT inducing the smallest increase from rest, while increases in neurotrophic factors would be intensity-dependent. In a randomized crossover design, 24 healthy adults (nine females) performed three exercise protocols: (i) MICT (30 min), (ii) HIIT (4 × 4 min at 85% HR), and (iii) SIT (4 × 30 s supramaximal).

Intermittent post-exercise sauna bathing improves markers of exercise capacity in hot and temperate conditions in trained middle-distance runners.

Purpose: This study investigated whether intermittent post-exercise sauna bathing across three-weeks endurance training improves exercise heat tolerance and exercise performance markers in temperate conditions, compared to endurance training alone. The subsidiary aim was to determine whether exercise-heat tolerance would further improve following 7-Weeks post-exercise sauna bathing.

Methods: Twenty middle-distance runners (13 female; mean ± SD, age 20 ± 2 years, [Formula: see text]O 56.

Impact of whole body passive heat stress and arterial shear rate modification on radial artery function in young men.

We sought to determine how whole body heating acutely influences radial artery function, characterized using flow-mediated dilation (FMD) and low-flow-mediated constriction (L-FMC), and the mechanistic role of shear rate modification on radial artery functional characteristics during heating. Eleven young healthy men underwent whole body heating (water-perfused suit) sufficient to raise the core temperature by +1°C. Trials were repeated with (heat + WC) and without (heat) the application of a wrist cuff located distal to the radial artery examined, known to prevent increases in mean and anterograde shear rates but increase retrograde shear rate.

Exercise-induced elevations in cerebral blood velocity are greater in running compared to cycling at higher intensities.

The optimal exercise intensity and modality for maximizing cerebral blood flow (CBF) and hence potential exposure to positive, hemodynamically derived cerebral adaptations is yet to be fully determined. This study compared CBF velocity responses between running and cycling across a range of exercise intensities. Twenty-six participants (12 females; age: 26 ± 8 years) completed four exercise sessions; two mode-specific maximal oxygen consumption (VO ) tests, followed by (order randomized) two incremental exercise protocols (3-min stages at 35%, 50%, 65%, 80%, 95% VO ).

Pathophysiological Mechanisms by which Heat Stress Potentially Induces Kidney Inflammation and Chronic Kidney Disease in Sugarcane Workers.

Background: Chronic kidney disease of non-traditional origin (CKDnt) is common among Mesoamerican sugarcane workers. Recurrent heat stress and dehydration is a leading hypothesis. Evidence indicate a key role of inflammation.

Preventing kidney injury among sugarcane workers: promising evidence from enhanced workplace interventions.

Objectives: To assess if improvement of working conditions related to heat stress was associated with improved kidney health outcomes among sugarcane harvest workers in Chichigalpa, Nicaragua, a region heavily affected by the epidemic of chronic kidney disease of non-traditional origin.

Methods: Based on our findings during the 2017-2018 harvest (harvest 1), recommendations that enhanced the rest schedule and improved access to hydration and shade were given before the 2018-2019 harvest (harvest 2). Actual work conditions during harvest 2 were then observed.

Insulation and Evaporative Resistance of Clothing for Sugarcane Harvesters and Chemical Sprayers, and Their Application in PHS Model-Based Exposure Predictions.

Many workers are exposed to heat stress that can be exacerbated by the type of clothing they wear. The resulted heat strain can lead to short or long-term heat-related disorders. This study aimed to measure clothing properties of sugarcane field workers and evaluate the heat strain by an international standard, predicted heat strain model (PHS).