Effects of different levels of physical activity on arterial stiffness and physical fitness performance in firefighters

Abstract

Background: Firefighters have lower levels of physical activity while on call. It is critical to understand the impact of firefighters' physical activity on arterial stiffness. This study classified groups by physical activity level and combined peripheral vascular monitor measurement to explore the relationships between the level of physical activity and cardiovascular (CV) risk and physical fitness (PF) of firefighters, as well as the acute response to arterial stiffness (AS) following maximal aerobic exercise test (MAET) intervention. Methods: The International Physical Activity Questionnaire (IPAQ) was used to classify the participants into 3 groups: low, moderate, and high level of physical activity group, respectively. A total of 36 participants were recruited, 12 in each group. Participants were assessed for body composition, rest brachial-ankle pulse wave velocity (baPWV), handgrip strength (HGS), maximal oxygen uptake (V̇O_2max), and MAET baPWV. Results: In the three groups, significant differences were observed in V̇O_2max, HGS, relative fat mass (%FM), body mass index (BMI), muscle mass ratio (MMR), and Rest baPWV (p < 0.05). After maximal aerobic exercise, the MAET baPWV values decreased significantly in all groups (all p < 0.001). Rest baPWV was significantly correlated with firefighters' age, seniority, metabolic equivalents (METs), height and muscle mass (MM) (p < 0.05). Conclusions: Firefighters with high levels of physical activity had better body composition and physical fitness and lower Rest baPWV. In all three groups, baPWV was lower after the MAET than before it. Therefore, regardless of a firefighter's level of physical activity, high-intensity aerobic exercise may have a beneficial effect on arterial stiffness.

Keywords: arteriosclerosis; body composition; firefighter; physical training.

Figure 1

Experimental procedure description.

Figure 2

Changes in baPWV after maximal aerobic exercise testing for LPAL, MPAL, and HPAL. LPAL, low level of physical activity group. MPAL, moderate level of physical activity group. HPAL, high level of physical activity group. Gray bars represent the group mean. Solid black dots represent individual data points at pre and post-test, respectively. ** Indicates post-test was significantly difference from pre-test, p < 0.001.