The present study analyses whether the stress and strain experienced by seafarers differ between the various occupational groups on board container ships. In a maritime field study, 323 sailors on 22 container ships were asked to complete a questionnaire and were biometrically surveyed. In addition, a survey of energy expenditure and heart rate (variability) was carried out with the SenseWear^® armband monitor and the Polar RS800 watch, respectively. The activity data objectively collected by the armband monitor showed an average sleep duration of 5.0 h per day, with particularly short sleep episodes amongst nautical officers. This occupational group also significantly more frequently reported sleep deficits (67%). The highest work-related energy expenditure per day was among the deck ratings (801 kcal), followed by the engine room personnel (777 kcal), and finally the nautical officers (568 kcal). The last-mentioned group, who were also the most likely to experience mental stress in the workplace, had the lowest heart rate variability compared to the other occupational groups. The average working time was the only stress parameter that correlated significantly negatively with the heart rate variability (r = −0.387; p = 0.002). Overall, job-related stressors of seafarers on board should be objectified in further studies and occupational group-specific health promotion programmes should be developed.

Overweight and obesity is quite prevalent among seafarers. The present study examined differences in BMI and their association with weight, shape and nutrition related attitudes and perceptions among seafarer from Kiribati, a Pacific Island Group, and European origin. The Seafarer Nutrition Study compared 48 Kiribati and 33 European male seafarers from 4 commercial merchant ships. BMI was calculated from measured weight and height. Attitudes to weight, shape and nutrition and disinhibition of control as a characteristic of eating behavior were assessed in a structured interview. Differences between the two groups were examined using t-tests and Chi-square-tests as appropriate. Associations between the variables were examined using Multiple Regression Analysis (MRA) and correlations. Kiribati seafarer had significantly higher BMI than Europeans (30.3 ± 4.2 vs. 25.6 ± 3.4; p < 0.001). However, MRA indicated that Kiribati were choosing thinner shapes as being “most similar” to their appearance than Europeans with the same BMI (B = − 1.14; p < 0.05). In addition, Kiribati had significantly higher scores of disinhibition than Europeans (5.6 ± 2.2 vs. 4.3 ± 2.1; p < 0.01), and disinhibition correlated with BMI in the Kiribati (r = 0.39; p < 0.01), but not in the European group (r = 0.17; n.s.). For Kiribati seafarers the nutrition situation on board represents a highly tempting westernized food environment. Their tendency to disinhibited eating facilitates overconsumption and weight gain, and self-evaluation of their shapes as being thinner than comparable Europeans may hamper appropriate weight control behavior.

Seafarers experience a lot of job-related risk factors for cardiovascular diseases (CVD). Considering the healthy-worker effect due to the biennial pre-employment examination and the periodical medical fitness tests, a (slightly) elevated risk for CVD among seafarers is assumed compared to the reference population ashore. In seafaring, the most important, influenceable risk factors for CVD refer to the ship-specific stress situation, the malnutrition and the lack of exercises on board. Furthermore, the prognosis of acute severe CVD often depends on the measures taken in the first few hours after occurrence of the symptoms. Owing to the lack of health professionals on board and the limited treatment options of events at sea, effective cardio-pulmonary resuscitation is often delayed and the outcome of cardiac events is worse compared to that ashore. Seafarers experience a lot of job-related risk factors for cardiovascular diseases (CVD). Considering the healthy-worker effect due to the biennial pre-employment examination and the periodical medical fitness tests, a (slightly) elevated risk for CVD among seafarers is assumed compared to the reference population ashore. In seafaring, the most important, influenceable risk factors for CVD refer to the ship-specific stress situation, the malnutrition and the lack of exercises on board. Furthermore, the prognosis of acute severe CVD often depends on the measures taken in the first few hours after occurrence of the symptoms. Owing to the lack of health professionals on board and the limited treatment options of events at sea, effective cardio-pulmonary resuscitation is often delayed and the outcome of cardiac events is worse compared to that ashore.

The present study describes the intercultural differences in the perception of stress and the preparation of seafarers. Three hundred twenty-three seafarers (156 [48.3%] Europeans and 167 [51.7%] Southeast Asians) were interviewed about their subjective stress on board. According to the interviews with ship's officers, mostly represented by Europeans, mental stress was most often due to high responsibilities (82.0%), extensive administrative tasks (81.1%) and lack of qualification of seafarers (64.8%). Subjectively, the Europeans questioned were significantly more likely to experience mental stress on board than the Southeast Asians (74.2% vs. 56.3%), whereas the latter were more prone to being physically stressed. 43.1% of the Southeast Asian seafarers often felt lonely on board compared with 26.2% of the Europeans. Preparation for maritime-specific stress in the form of specific training units is only provided in 1 of the 5 universities surveyed. The most important reason for this is a lack of time. Intercultural leadership training was also only offered at one university. In view of the many psychophysical stressors in daily life on a ship and the lacking respective education, it is recommended to integrate stress management and diversity training in intercultural communication in the higher education of future superiors on board.