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Shortened Recovery Period Between Firefighting Work Bouts Increases Cardiac Response Disproportionately With
Philippe Gendron1, François Trudeau, Louis Laurencelle
1Département des sciences de l'activité physique [Department of Physical Activity Sciences] (Mr Gendron, Dr Trudeau, Dr Laurencelle, Dr Lajoie); Département d'anatomie [Anatomy Department] (Mr Gendron); Faculté des sciences de l'activité physique, [Faculty of Physical Education and Sports], Université de Sherbrooke [Sherbrooke University] (Dr Goulet); Département des sciences infirmières [Nursing Department] (Dr Houle), Université du Québec à Trois-Rivières (UQTR) [University of Québec in Trois-Rivières (UQTR)], Trois-Rivières, Québec, Canada.
Objective:
To compare physiological responses between two firefighting simulations with different recovery periods, one having work bouts intercalated by a shortened recovery period.
Methods:
Thirteen male firefighters participated in two different simulations, which comprised two identical 25-minute effort bouts (E1 and E2) intercalated by a recovery period of either 20 (T20) or 5 (T5) minutes.
Results:
From E1 to E2, the increase of mean heart rate (HR) (26 ± 5 vs 14 ± 5 bpm, P < 0.001) and mean VO2 (1.8 ± 0.4 vs 1.3 ± 0.4 mL kg min, P < 0.001) was higher in T5 than in T20.
Conclusion:
Results indicate that a shortened recovery time between firefighting work bouts intensifies cardiac strain disproportionately with metabolic rate, since mean HR increased by 19.3% and 10.8% while mean VO2 increased by only 7.2% and 5.0% in T5 and T20, respectively.
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