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Recreational possibilities for seafarers during shipboard leisure time
Marcus Oldenburg1, Hans-Joachim Jensen2
1Institute for Occupational and Maritime Medicine Hamburg (ZfAM), University Medical Center Hamburg-Eppendorf (UKE), Seewartenstrasse 10, 20459, Hamburg, Germany. marcus.oldenburg@bgv.hamburg.de.
Purpose:
This study is aiming to document the leisure time opportunities and their actual utilization on board merchant ships.
Methods:
A scientist examined the whole crew on board 22 container ships (323 seafarers; participation rate 88.5%). Data about energy consumption and heart rate were continuously collected during the seafarers' leisure and sleeping time through a SenseWear® wrist monitor and a Polar watch RS 800 worn for at least 2.5 days.
Results:
The seafarers spent an average of 28.2% of the day for leisure time activities and 32.6% for sleeping. A significantly higher energy consumption was found among deck ratings compared to engine room personnel and nautical officers. Across all occupational groups, the variability of the heart rate was lower during sleeping hours than during leisure time. Suggestions for substantial improvement of the leisure time opportunities on board included more frequent and free opportunities for telecommunication (59.1%), shorter work assignments, and a stronger cohesion of the crew. The following coping strategies were paramount: "calming down/settling down" (41.9%), getting in touch with the family (32.0%) and relaxing/sleeping (30.4%).
Conclusions:
The limited heart rate variability during sleeping hours suggests a reduced quality of sleep that might be due to the permanent heaving motions of the vessel, noise, and vibration. The (deck) ratings had more physical activities that corresponded with their higher energy consumption during leisure time. Altogether, there is a need to optimize opportunities for relaxation and recreation on board, taking into consideration characteristics of the different occupational and ethnic groups.
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