Hostler David, Colburn Deanna, Rittenberger Jon C, Reis Steven E
Prehosp Emerg Care. 2016 Nov-Dec;20(6):681-687. doi: 10.3109/10903127.2016.1168890. Epub 2016 Apr 14.
Fire suppression is a physically demanding occupation that often results in significant heat stress and hypohydration. Guidelines for the number of work intervals allowed before a structured recovery were consensus derived and have not been tested.
Apparently healthy firefighters were recruited for this field study. Subjects were assigned to two or three bouts of live fire training prior to 20 minutes of structured recovery to provide rehydration and cooling. After recovery, the subjects completed a timed test of firefighting skills.
Extending the fire suppression interval from two to three work periods before a structured recovery period increased core temperature and the time required to perform a high intensity circuit of firefighting skills immediately following recovery. A mild hypotension was noted during recovery but the groups did not differ for blood pressure, heart rate, or firefighter perception of thermal strain or exertion.
This is the first study to examine the physiologic effects of structural firefighting work intervals on recovery and subsequent performance. Both groups experienced maximal cardiovascular strain during fire suppression but extending the work interval worsened heat stress and negatively affected certain aspects of performance immediately following the recovery period.
灭火是一项对体力要求很高的职业，经常会导致严重的热应激和水分过少。关于在进行有组织的恢复之前允许的工作间隔次数的指导方针是通过共识得出的，尚未经过测试。
招募表面健康的消防员参与这项现场研究。在进行20分钟有组织的恢复（以补充水分和降温）之前，让受试者进行两到三轮实火训练。恢复后，受试者完成一项消防技能定时测试。
在有组织的恢复期之前，将灭火间隔从两个工作时段延长至三个工作时段会使核心体温升高，并且在恢复后立即进行高强度消防技能循环所需的时间增加。恢复过程中出现了轻度低血压，但两组在血压、心率、消防员对热应激或劳累的感知方面没有差异。
这是第一项研究结构性灭火工作间隔对恢复及后续表现的生理影响的研究。两组在灭火过程中都经历了最大程度的心血管应激，但延长工作间隔会加重热应激，并对恢复期后的某些表现方面产生负面影响。
