Author(s): JAVANMARDI, S., RAPPELT, L., HEINKE, L., FREIWALD, J., NIEDERER, D., BAUMGART, C., Institution: UNIVERSITY OF WUPPERTAL, Country: GERMANY, Abstract-ID: 853

INTRODUCTION:
A higher pace of work on repetitive tasks may affect physical strain and work-related outcomes like error rate in industrial workers. However, the effects of different work paces on cardiovascular variables have not yet been investigated. This study elucidated the impact of work pace on cardiorespiratory factors and assessed workers’ comfort, effort, and load. By understanding the needs of industrial workers, we can develop tailored health interventions.
METHODS:
Twelve industrial workers (age: 44 ± 9 years; BMI: 27.7 ± 4.5 kg/m2) with at least one year of experience at a repetitive workstation and no acute injuries or physical limitations were tested on three different production environments (comparable repetitive tasks and equal amount of product handled). Work paces at 100%, 115%, and 130% of the internal target yield were randomly assessed. At each pace, a 5-minute familiarization was followed by a 5-minute data collection. Every minute, participants received feedback to adjust their pace. The total ventilation (VE), oxygen uptake (VO2), carbon dioxide release (VCO2), respiratory exchange ratio (RER; Metamax 3 B, Cortex, Leipzig), and heart rate (HR; Polar H10 chest band) were measured. Thereon, energy expenditure (EE) was calculated. In addition, the carried load (CL) was recorded in kg. Moreover, for each pace, all participants provided feedback on their comfort level using the visual analogue scale (VAS; 0-100) and their perceived effort (RPE; 0-10). One-way ANOVA was performed using R version 4.2.2.
RESULTS:
No significant between-pace difference was found for RER, HR, RPE, or comfort (p ≤ .993; ƞp²≥ .001). However, significant between-pace differences were found for VE, VO2, VCO2, EE, and CL (p ≤ .042; ƞp²≥ .25). Post hoc comparisons revealed significant differences with small effect sizes between 100% and 130% in VE (15.9±2.8 vs. 17.1±3.3 l/min, p=.041, SMD=.38), VO2 (.48±.09 vs. .52±.12 l/min, p=.006, SMD=.35), VCO2 (.43±.09 vs. .46±.11l/min, p=.023, SMD=.34), and EE (165.9±33.4 vs. 178.8±40.1 kcal/h, p=.008; SMD=.35). Significant large pace effects were found for CL between 100% and 130% (14.6±1.4 vs. 18.4±1.8kg, p<.001, SMD=2.38), and between 115% and 130% (16.2±1.7 vs. 18.4±1.8kg, p=.007, SMD=1.25).
CONCLUSION:
A work pace of 130% increases the physiological demand of industrial workers. However, whether the amount of changes and a load variation of only 4 kg/5 min influence health-related factors is questionable. Nevertheless, this study sheds light on the physiological profile of industrial workers, offering insights that may be valuable for informing preventive health-promotion strategies. Specifically, interventions in physical activity, job rotation or nutrition should be tailored to address the specific demands identified in this study.