Age-related reductions in heart rate variability do not worsen during exposure to humid compared to dry heat: A secondary analysis.

We conducted a secondary analysis to investigate whether age-related attenuations in heart rate variability (HRV) worsen during exposure to moderate, dry (36.5°C, 20% RH) or humid (36.5°C, 60% RH) heat conditions that resulted in greater body heat storage among older compared to young participants, and during humid compared to dry heat, regardless of age.

Age alters cardiac autonomic modulations during and following exercise-induced heat stress in females.

The aim of this study was to examine the effect of natural ageing on heart rate variability during and following exercise-induced heat stress in females. Eleven young (∼24 years) and 13 older (∼51 years), habitually active females completed an experimental session consisting of baseline rest, moderate intensity intermittent exercise (four 15-min bouts separated by 15-min recovery) and 1-hour of final recovery in a hot and dry (35°C, 20% relative humidity) environment. Respiratory and heart rate recordings were continuously logged with 10-min periods analysed at the end of: baseline rest; each of the exercise and recovery bouts; and during the 1-hour final recovery period.

Amplified Pilot Head Vibration and the Effects of Vibration Mitigation on Neck Muscle Strain.

Introduction: Rotary wing pilot neck strain is increasing in prevalence due to the combined effects of head supported mass (e.g., Night Vision Goggles, head mounted displays) and whole-body vibration.

The Damage Control Surgery in Austere Environments Research Group (DCSAERG): A dynamic program to facilitate real-time telementoring/telediagnosis to address exsanguination in extreme and austere environments.

Hemorrhage is the most preventable cause of posttraumatic death. Many cases are potentially anatomically salvageable, yet remain lethal without logistics or trained personnel to deliver diagnosis or resuscitative surgery in austere environments. Revolutions in technology for remote mentoring of ultrasound and surgery may enhance capabilities to utilize the skill sets of non-physicians.

The marriage of surgical simulation and telementoring for damage-control surgical training of operational first responders: A pilot study.

Background: Hemorrhage is the leading cause of preventable posttraumatic death. Many such deaths may be potentially salvageable with remote damage-control surgical interventions. As recent innovations in information technology enable remote specialist support to point-of-care providers, advanced interventions, such as remote damage-control surgery, may be possible in remote settings.

Technical innovations that may facilitate real-time telementoring of damage control surgery in austere environments: a proof of concept comparative evaluation of the importance of surgical experience, telepresence, gravity and mentoring in the conduct of damage control laparotomies.

Bleeding to death is the most preventable cause of posttraumatic death worldwide. Despite the fact that many of these deaths are anatomically salvageable with relatively basic surgical interventions, they remain lethal in actuality in prehospital environments when no facilities and skills exist to contemplate undertaking basic damage control surgery (DCS). With better attention to prehospital control of extremity hemorrhage, intracavitary bleeding (especially intraperitoneal) remains beyond the scope of prehospital providers.

Increased Air Velocity Reduces Thermal and Cardiovascular Strain in Young and Older Males during Humid Exertional Heat Stress.

Older adults have been reported to have a lower evaporative heat loss capacity than younger adults during exercise when full sweat evaporation is permitted. However, it is unclear how conditions of restricted evaporative and convective heat loss (i.e.

Preservation of cognitive performance with age during exertional heat stress under low and high air velocity.

Unlabelled: Older adults may be at greater risk for occupational injuries given their reduced capacity to dissipate heat, leading to greater thermal strain and potentially cognitive decrements.

Purpose: To examine the effects of age and increased air velocity, during exercise in humid heat, on information processing and attention.

Methods: Nine young (24 ± 1 years) and 9 older (59 ± 1 years) males cycled 4 × 15 min (separated by 15 min rest) at a fixed rate of heat production (400 W) in humid heat (35°C, 60% relative humidity) under 0.

Older firefighters are susceptible to age-related impairments in heat dissipation.

Purpose: The aging-induced reduction in whole-body heat loss (HL) capacity generates concerns regarding the continued participation of older workers in occupations such as firefighting. We compared HL and change in body heat storage (S) during intermittent exercise in warm/dry and warm/humid conditions among older male firefighters (OLDER, n = 9, age = 54.7 ± 2.

Treatment of exertional heat stress developed during low or moderate physical work.

Purpose: We examined whether treatment for exertional heat stress via ice water immersion (IWI) or natural recovery is affected by the intensity of physical work performed and, thus, the time taken to reach hyperthermia.

Methods: Nine adults (18-45 years; 17.9 ± 2.

Changes in heart rate variability during the induction and decay of heat acclimation.

Purpose: We evaluated the changes in core temperature, heart rate, and heart rate variability (HRV) during the induction and decay of heat acclimation.

Methods: Ten males (23 ± 3 years; 79.5 ± 3.

Increased air velocity during exercise in the heat leads to equal reductions in hydration shifts and interleukin-6 with age.

Purpose: The effectiveness of increased air velocity in reducing hydration shifts and physiological strain during work in the heat was examined in young and older males.

Methods: Ten young (mean ± SE, 24 ± 1 years) and 10 older (59 ± 1 years) males, matched for height, mass, and body surface area, cycled 4 × 15-min at moderate-to-heavy heat production (400 W), with 15-min rest separations between exercise bouts (final recovery 30 min), while wearing work clothing in humid heat (35 °C, 60 % relative humidity) under low (~0.5 m s(-1)) and high (~3.

Age-related differences in heat loss capacity occur under both dry and humid heat stress conditions.

This study examined the progression of impairments in heat dissipation as a function of age and environmental conditions. Sixty men (n = 12 per group; 20-30, 40-44, 45-49, 50-54, and 55-70 yr) performed four intermittent exercise/recovery cycles for a duration of 2 h in dry (35°C, 20% relative humidity) and humid (35°C, 60% relative humidity) conditions. Evaporative heat loss and metabolic heat production were measured by direct and indirect calorimetry, respectively.

Inflammatory responses of older firefighters to intermittent exercise in the heat.

Purpose: Repeated strenuous work in the heat may predispose firefighters to augmented immune responses and inflammation. This study examined the immune responses in 12 older Firefighters (FF) and 12 older Non-Firefighters (Non-FF), and a group of 6 young FF and 6 young Non-FF, following intermittent exercise in the heat.

Methods: The participants, matched for age, body surface area, body composition, and VO(2peak), cycled 4 × 15 min at moderate-to-high heat production (400 W), each followed by 15-min rest, in dry [10-20% relative humidity (RH)] and humid (60% RH) heat (35 °C).

Heart rate variability during exertional heat stress: effects of heat production and treatment.

Purpose: We assessed the efficacy of different treatments (i.e., treatment with ice water immersion vs.