The fan cooling vest use reduces thermal and perceptual strain during outdoor exercise in the heat on a sunny summer day.

The fan cooling vest is coming into very common use by Japanese outdoor manual workers. We examined that to what extent using this vest reduces thermal strain and perception during outdoor exercise in the heat on a sunny summer day. Ten male baseball players in high school conducted two baseball training sessions for 2-h with (VEST) or without (CON) a commercially available fan cooling vest on a baseball uniform.

Thermal strain is greater in the late afternoon than morning during exercise in the gym without airflow and air conditioning on a clear summer day.

Introduction: There are no reports examining the time-of-day effect on team training sessions in the gym without airflow and air conditioning on thermal strain in the summer heat. We investigated this effect during badminton training sessions on a clear summer day.

Methods: Nine male high school badminton players (Mean ± SD; age 17.

Prior heat exposure diminishes upper-body endurance work capacity and maximal arm and leg strength in young men.

Workers often experience heat exposure before manual labour. This study investigated whether prior heat exposure diminished upper-body endurance work capacity and maximal isokinetic arm and leg strength in young men. Ten male participants completed two trials in a climatic chamber maintained at 25°C with 50% relative humidity.

The use of sun-shade on safe heat exposure limit on a sunny summer day: a modelling study in Japan.

Sustainable methods are required to reduce the risks of thermal strain and heat-related illness without exacerbating greenhouse gas emissions. We investigated the effects of sun-shade use on safe heat exposure limit on a sunny summer day using historical climate data in Japan. We simulated a heat-acclimatised person standing at rest (metabolic heat production, 70 W·m) and during light work (100 W·m) on an asphalt pavement in the sun and sun-shade.

Cooling Between Exercise Bouts and Post-exercise With the Fan Cooling Jacket on Thermal Strain in Hot-Humid Environments.

This study investigated the effects of cooling between exercise bouts and post-exercise with a commercially available fan cooling jacket on thermal and perceptual responses during and following exercise in hot-humid environments. Ten male athletes completed two 30 min cycling bouts at a constant workload (1.4 watts⋅kg of body mass) with a 5 min recovery period in between.

Roundtable on Preseason Heat Safety in Secondary School Athletics: Environmental Monitoring During Activities in the Heat.

Objective: To develop best-practice recommendations using thermal indices to determine work-to-rest ratios and facilitate further implementation of environmental monitoring for heat safety in secondary school athletics in the United States.

Data Sources: A narrative review of the current literature on environmental monitoring for heat safety during athletics was conducted by content experts. A list of action-oriented recommendations was established from the narrative review and further refined using the Delphi method.

Greater thermoregulatory strain in the morning than late afternoon during judo training in the heat of summer.

Purpose: The time-of-day variations in environmental heat stress have been known to affect thermoregulatory responses and the risk of exertional heat-related illness during outdoor exercise in the heat. However, such effect and risk are still needed to be examined during indoor sports/exercises. The current study investigated the diurnal relationships between thermoregulatory strain and environmental heat stress during regular judo training in a judo training facility without air conditioning on a clear day in the heat of summer.

Combined effects of solar radiation and airflow on endurance exercise capacity in the heat.

This study investigated the combined effects of different levels of solar radiation and airflow on endurance exercise capacity and thermoregulatory responses during exercise-heat stress. Ten males cycled at 70% peak oxygen uptake until exhaustion in an environmental chamber (30°C, 50% relative humidity). Four combinations of solar radiation and airflow were tested (800 W⋅m and 10 km⋅h [High-Low], 800 W⋅m and 25 km⋅h [High-High], 0 W⋅m and 10 km⋅h [No-Low], and 0 W⋅m and 25 km⋅h [No-High]).

Rising vs. falling phases of core temperature on endurance exercise capacity in the heat.

Purpose: Core temperature (T) shows rising (05:00-17:00 h) and falling (17:00-05:00 h) phases. This study examined the time-of-day effects on endurance exercise capacity and heat-loss responses to control T in the heat at around the midpoint of the rising and falling phases of T.

Methods: Ten male participants completed cycling exercise at 70% peak oxygen uptake until exhaustion in the heat (30 °C, 50% relative humidity).

Solar radiation and the validity of infrared tympanic temperature during exercise in the heat.

We investigated the validity of infrared tympanic temperature (IR-T) during exercise in the heat with variations in solar radiation. Eight healthy males completed stationary cycling trials at 70% peak oxygen uptake until exhaustion in an environmental chamber maintained at 30°C with 50% relative humidity. Three solar radiation conditions, 0, 250 and 500 W/m, were tested using a ceiling-mounted solar simulator (metal-halide lamps) over a 3 × 2 m irradiated area.

Solar Radiation Exposure Has Diurnal Effects on Thermoregulatory Responses During High-Intensity Exercise in the Heat Outdoors.

Otani, H, Goto, T, Goto, H, Hosokawa, Y, and Shirato, M. Solar radiation exposure has diurnal effects on thermoregulatory responses during high-intensity exercise in the heat outdoors. J Strength Cond Res 33(10): 2608-2615, 2019-This study investigated the diurnal effects of variations in solar radiation associated with changing solar elevation angle on thermoregulatory responses during high-intensity exercise in the heat outdoors.

Exposure to high solar radiation reduces self-regulated exercise intensity in the heat outdoors.

High radiant heat load reduces endurance exercise performance in the heat indoors, but this remains unconfirmed in outdoor exercise. The current study investigated the effects of variations in solar radiation on self-regulated exercise intensity and thermoregulatory responses in the heat outdoors at a fixed rating of perceived exertion (RPE). Ten male participants completed 45-min cycling exercise in hot outdoor environments (about 31°C) at a freely chosen resistance and cadence at an RPE of 13 (somewhat hard).

Diurnal effects of prior heat stress exposure on sprint and endurance exercise capacity in the heat.

Active individuals often perform exercises in the heat following heat stress exposure (HSE) regardless of the time-of-day and its variation in body temperature. However, there is no information concerning the diurnal effects of a rise in body temperature after HSE on subsequent exercise performance in a hot environnment. This study therefore investigated the diurnal effects of prior HSE on both sprint and endurance exercise capacity in the heat.

Air velocity influences thermoregulation and endurance exercise capacity in the heat.

This study examined the effects of variations in air velocity on time to exhaustion and thermoregulatory and perceptual responses to exercise in a hot environment. Eight male volunteers completed stationary cycle exercise trials at 70% peak oxygen uptake until exhaustion in an environmental chamber maintained at 30 °C and 50% relative humidity. Four air velocity conditions, 30, 20, 10, and 0 km/h, were tested, and the headwind was directed at the frontal aspect of the subject by 2 industrial fans, with blade diameters of 1 m and 0.

Time-of-day effects of exposure to solar radiation on thermoregulation during outdoor exercise in the heat.

High solar radiation has been recognised as a contributing factor to exertional heat-related illness in individuals exercising outdoors in the heat. Although solar radiation intensity has been known to have similar time-of-day variation as body temperature, the relationship between fluctuations in solar radiation associated with diurnal change in the angle of sunlight and thermoregulatory responses in individuals exercising outdoors in a hot environment remains largely unknown. The present study therefore investigated the time-of-day effects of variations in solar radiation associated with changing solar elevation angle on thermoregulatory responses during moderate-intensity outdoor exercise in the heat of summer.

Separate and combined effects of exposure to heat stress and mental fatigue on endurance exercise capacity in the heat.

Purpose: This study investigated the effects of exposure to pre-exercise heat stress and mental fatigue on endurance exercise capacity in a hot environment.

Methods: Eight volunteers completed four cycle exercise trials at 80% maximum oxygen uptake until exhaustion in an environmental chamber maintained at 30 °C and 50% relative humidity. The four trials required them to complete a 90 min pre-exercise routine of either a seated rest (CON), a prolonged demanding cognitive task to induce mental fatigue (MF), warm water immersion at 40 °C during the last 30 min to induce increasing core temperature (WI), or a prolonged demanding cognitive task and warm water immersion at 40 °C during the last 30 min (MF + WI).

Effects of solar radiation on endurance exercise capacity in a hot environment.

Purpose: The present study investigated the effects of variations in solar radiation on endurance exercise capacity and thermoregulatory responses in a hot environment.

Methods: Eight male volunteers performed four cycle exercise trials at 70 % maximum oxygen uptake until exhaustion in an environmental chamber maintained at 30 °C and 50 % relative humidity. Volunteers were tested under four solar radiation conditions: 800, 500, 250 and 0 W/m(2).

Effect of the volume of fluid ingested on urine concentrating ability during prolonged heavy exercise in a hot environment.

This study examined the effect of the volume of fluid ingested on urine concentrating ability during prolonged heavy exercise in a hot environment at low levels of dehydration. Seven healthy males performed 105 min of intermittent cycle exercise at 70% maximum oxygen uptake (32°C, 60% relative humidity) while receiving no fluid ingestion (NF), voluntary fluid ingestion (VF), partial fluid ingestion equivalent to one-half of body mass loss (PF), and full fluid ingestion equivalent to body mass loss (FF). Fluid (5°C, 3.

Influence of relative humidity on prolonged exercise capacity in a warm environment.

This study examined the influence of relative humidity on endurance exercise performance in a warm environment. Eight male volunteers performed four cycle exercise trials at 70% maximum oxygen uptake until volitional exhaustion in an environmental chamber maintained at 30.2 ± 0.