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Background: To limit exposures to occupational heat stress, leading occupational health and safety organizations recommend work–rest regimens to prevent core temperature from exceeding 38°C or increasing by ≥1°C. This scoping review aims to map existing knowledge of the effects of work–rest regimens in hot environments and to propose recommendations for future research based on identified gaps. Methods: We performed a search of 10 databases to retrieve studies focused on work–rest regimens under hot conditions. Results: Forty‐nine articles were included, of which 35 were experimental studies. Most studies were conducted in laboratory settings, in North America (71%), on healthy young adults, with 94% of the 642 participants being males. Most studies (66%) employed a protocol duration ≤240 min (222 ± 162 min, range: 37–660) and the time‐weighted average wet‐bulb globe temperature was 27 ± 4°C (range: 18–34). The work–rest regimens implemented were those proposed by the American Conference of Governmental and Industrial Hygiene (20%), National Institute of Occupational Safety and Health (11%), or the Australian Army (3%). The remaining studies (66%) did not mention how the work–rest regimens were derived. Most studies (89%) focused on physical tasks only. Most studies (94%) reported core temperature, whereas only 22% reported physical and/or mental performance outcomes, respectively. Of the 35 experimental studies included, 77% indicated that core temperature exceeded 38°C. Conclusions: Although work–rest regimens are widely used, few studies have investigated their physiological effectiveness. These studies were mainly short in duration, involved mostly healthy young males, and rarely considered the effect of work–rest regimens beyond heat strain during physical exertion. [ABSTRACT FROM AUTHOR]

Planet Earth is warming at an unprecedented rate and our future is now assured to be shaped by the consequences of more frequent hot days and extreme heat. Humans will need to adapt both behaviorally and physiologically to thrive in a hotter climate. From a physiological perspective, countless studies have shown that human heat acclimation increases thermoeffector output (i.e., sweating and skin blood flow) and lowers cardiovascular strain (i.e., heart rate) during heat stress. However, the mechanisms mediating these adaptations remain understudied. Furthermore, several possible benefits of heat acclimation for other systems and functions involved in maintaining health and performance during heat stress remain to be elucidated. This review summarizes recent advances in human heat acclimation, with emphasis on recent studies that (1) advanced our understanding of the mechanisms mediating improved thermoeffector output and (2) investigated adaptations that go beyond those classically associated with heat acclimation. We highlight that these studies have contributed to a better understanding of the integrated physiological responses underlying human heat acclimation while leaving key unanswered questions that will need to be addressed in the future. What is the topic of this review?This review summarizes studies that advance our understanding of the mechanisms mediating improved thermoeffector output following heat acclimation and investigate adaptations that go beyond those classically associated with heat acclimation.What advances does it highlight?Most studies that investigated possible mechanisms mediating greater thermoeffector output following heat acclimation have focused on end‐organ responses. Some evidence suggests that heat acclimation improves cardiac function, body fluid regulatory functions, and preserves cognitive performance under heat stress. However, these conclusions are based on limited and conflicting data. [ABSTRACT FROM AUTHOR]

Intradialytic exercise is feasible and yields substantial clinical benefits in middle-aged patients. However, evidence is scarce in older hemodialysis patients. Objective: To assess the feasibility and clinical benefits of supervised, intradialytic exercise in older patients. Methods: Multicenter one-arm feasibility study. The main outcome was feasibility (ease of recruitment, dropout rate, adherence, affective valence, and adverse events). The secondary outcomes were physical capacity (five-repetition sit-to-stand, 60-s sit-to-stand tests, and grip strength), quality of life (36-Item Short-Form Health Survey), quality of sleep (Pittsburgh Sleep Quality Index), depressive symptoms (Beck Depression Inventory), and dialysis efficacy (Kt/V and urea reduction ratio). Results: About 79% of the screened patients agreed to participate (n = 25, 73 [66–77] years). The dropout rate was high (32%), but adherence remained high among the participants who completed the study (94%). Improvements were found in the five-repetition sit-to-stand (p <.001), 60-s sit-to-stand tests (p =.028), 36-Item Short-Form Health Survey mental component score (p =.008), depressive symptoms (p =.006), and quality of sleep (p =.035). Conclusion: Supervised intradialytic exercise seems safe and beneficial in older patients. [ABSTRACT FROM AUTHOR]

Glanders is a contagious zoonotic disease caused by Burkholderia mallei. Following the detection of glanders positive horses using the OIE complement fixation test, the tissues of two horses were analysed by PCR. While PCR systems targeting the Burkholderia pseudomallei complex gave positive signals, the species‐specific PCR systems targeting B. mallei (fliP‐IS407A) and B. pseudomallei (orf11)—the OIE recommended targets—resulted in negative signals. However, the presence of B. mallei in these tissues was confirmed with a recently described B. mallei‐specific real‐time PCR system and genotyping with MLST‐ and SNP‐based methods, performed on the most positive tissue, identified a genotype closely related to B. mallei strains recently isolated in the Middle East. This study leads to recommendations regarding the use of PCR systems for the molecular diagnosis of glanders, especially in regions where the circulating B. mallei strains have not yet been fully genetically characterized. [ABSTRACT FROM AUTHOR]

We compared the effect of programmed (PFI) and thirst-driven (TDFI) fluid intake on prolonged cycling performance and exercise associated muscle cramps (EAMC). Eight male endurance athletes (26 ± 6 years) completed two trials consisting of 5 h of cycling at 61% V ˙ O 2 peak followed by a 20 km time-trial (TT) in a randomized crossover sequence at 30 °C, 35% relative humidity. EAMC was assessed after the TT with maximal voluntary isometric contractions of the shortened right plantar flexors. Water intake was either programmed to limit body mass loss to 1% (PFI) or consumed based on perceived thirst (TDFI). Body mass loss reached 1.5 ± 1.0% for PFI and 2.5 ± 0.9% for TDFI (p = 0.10). Power output during the 20 km TT was higher (p < 0.05) for PFI (278 ± 41 W) than TDFI (263 ± 39 W), but the total performance time, including the breaks to urinate, was similar (p = 0.48) between conditions. The prevalence of EAMC of the plantar flexors was similar between the drinking conditions. Cyclists competing in the heat for over 5 h may benefit from PFI aiming to limit body mass loss to <2% when a high intensity effort is required in the later phase of the race and when time lost for urination is not a consideration. [ABSTRACT FROM AUTHOR]