Heavy Physical Work: Cardiovascular Load in Male Construction Workers

Abstract

This study aimed to elucidate cardiovascular loads (CVL) in construction workers during work and leisure by relative heart rate (RHR) over several days. Furthermore, we sought to evaluate the level of CVL in relation to individual factors, work ability, musculoskeletal pain and subjective general health. From a group of 255 construction workers responding to the baseline questionnaire, the CVL during work and leisure time was determined by recording RHR in 42 workers over 3-4 days. Almost 60% of the workday was spent below 20% RHR. The mean RHR during work for all participants was 16% RHR, with large differences between professions. On average, the 42 workers spent 14% of the workday at a RHR above 33%, and four subjects (10%) had a mean RHR above 33% during work. Eight (19%) of the participants had a mean length of their workday exceeding calculated maximal acceptable work time. Seven persons (17%) experienced on average one or more episode(s) of 5 min or more continuously above 33% RHR. The cardiovascular load at work was significantly associated with age and V̇O(2max), but not with work ability, musculoskeletal pain or subjective general health.

Keywords: construction work; general health; musculoskeletal pain; physical demands; work ability.

Figure 1

Examples of single periods of measured work and leisure heart rate for a foreman and a carpenter. (A) work foreman; (B) leisure foreman; (C) work carpenter and (D) leisure carpenter.

Figure 2

Relative heart rate distribution during work and leisure presented as minutes with standard deviation. During work: All; n = 42, Bricklayer; n = 5, Carpenter; n = 12, Concrete worker; n = 8, Foreman; n = 4, Henchman; n = 8, Project manager; n = 5. During leisure: All; n = 36, Bricklayer; n = 3, Carpenter; n = 11, Concrete worker; n = 7, Foreman; n = 4, Henchman; n = 6, Project manager; n = 5.

Figure 3

Mean relative heart rate during work and maximal acceptable worktime for professions.

Figure 4

Number of episodes with mean RHR above 33% (exertion) or below 10% (rest) continuously for 5 min or more.