Impact of overnight traffic noise on sleep quality, sleepiness, and vigilant attention in long-haul truck drivers: Results of a pilot study.

This study aimed to evaluate the impact of traffic noise along the motorway on sleep quality, sleepiness, and vigilant attention in long-haul truck drivers. This was a randomized, crossover, within-subject controlled study. Healthy long-haul truck drivers spent 6 consecutive nights in a real truck berth with full sleep laboratory equipment. During 3 nights, subjects were exposed to replayed traffic noise alongside motorways, whereas the other 3 nights were without traffic noise. Polysomnography was recorded during the nights and numerous sleepiness tests and vigilance examinations were performed during the following standardized working day. Outcome measures were compared between noisy and silent nights using the paired Wilcoxon test. Ten healthy long-haul truck drivers with a mean age of 36.3 ± 7.3 years completed the study as planned. On noisy nights, subjects had greater latencies to the rapid eye movement (REM) phase (90 ± 32 min vs 69 ± 16 min, P = 0.074) and higher percentages of sleep stage 1 (13.7 ± 5.5% vs 11.2 ± 4.4%; P = 0.059). Subjects also rated their sleep quality as having been better during nights without noise (28.1 ± 3.7 vs 30.3 ± 6.2, P = 0.092). The impact of these differences on daytime sleepiness and vigilance was rather low; however, mean Karolinska Sleepiness Scale (KSS) scores measured during the course of the following day were higher on six out of eight occasions after noisy nights. The effects of overnight traffic noise on sleep quality are detectable but unlikely to have any major impact on the vigilant attention and driving performance of long haul-truck drivers with low nocturnal noise sensitivity. This might not be true for subgroups prone to sleeping disorders.

Multimodal in-vehicle lighting system increases daytime light exposure and alertness in truck drivers under Arctic winter conditions.

Drowsiness while driving negatively impacts road safety, especially in truck drivers. The present study investigated the feasibility and alerting effects of a daylight-supplementing in-truck lighting system (DS) providing short-wavelength enriched light before, during, and after driving. In a within-participants design, eight truck drivers drove a fully-loaded truck under wintry Scandinavian conditions (low daylight levels) with a DS or placebo system for five days. Subjective and objective measures of alertness were recorded several times daily, and evening melatonin levels were recorded three times per study condition. DS significantly increased daytime light exposure without causing negative side effects while driving. In addition, no negative carry-over effects were observed on evening melatonin and sleepiness levels or on nighttime sleep quality. Moreover, objective alertness (i.e., psychomotor vigilance) before and after driving was significantly improved by bright light exposure. This effect was accompanied by improved subjective alertness in the morning. This field study demonstrated that DS was able to increase daytime light exposure in low-daylight conditions and to improve alertness in truck drivers before and after driving (e.g., during driving rest periods). Further studies are warranted to investigate the effects of daylight-supplementing in-cabin lighting on driving performance and road safety measures.

Effects of a seat-integrated mobilization system during passive driver fatigue.

OBJECTIVE: The aim of this study is to evaluate the effectiveness of a seat-integrated mobilization system for maintaining vigilance under monotonous driving situations. METHOD: For this purpose, vigilance indicators were compared intra-individually in a test condition with mobilization (seat-integrated stimulation) and a placebo condition under standardized conditions in a real driving study (N = 31). During a monotonous two-hour ride, physiological (brain activity by the EEG alpha spindle rate), performance-based (reaction times) and subjective indicators were recorded. RESULTS: The necessary precondition for the paradigm of inducing fatigue through monotony was confirmed by a significant increase in the EEG alpha spindle rate and the subjective vigilance indices. The mobilization system had a significant impact on the most fatigue-sensitive parameter of the alpha spindle rate, whereas the other parameters of vigilance did not reflect a significant effect of mobilization. CONCLUSION: The Mobilization Seat is an effective measure to prevent drivers' fatigue during monotonous situations.

Food choice patterns of long-haul truck drivers driving through Germany, a cross sectional study.

BACKGROUND: Long-haul truck drivers are exposed to unfavorable working conditions affecting their health but information on truck drivers travelling through Europe is missing. The study aimed to describe the populations' characteristics and food choice patterns while working compared with eating patterns at home, taking weight status into account. METHODS: A cross-sectional survey using questionnaires in 12 languages conducted at two truck stops in Germany. RESULTS: Among 404 truck drivers of 24 nationalities, only 24% were normal weight while 46% were considered overweight and 30% obese. In regards to their health, more than half reported that they smoked and 32% reported at least one chronic disease. 37% ate their meals often or always at truck stops, while 6% never did so. The most common food items brought from home were fruits (62%) followed by sausages (50.6%), sandwiches (38.7%), self-cooked meals (37%), sweets (35.4%), and raw vegetables (31%). Bivariate analyses revealed differences in food choices during work and at home with more sausages, energy drinks and soft drinks, and canned foods eaten during trips. Fresh vegetables, legumes and fish were more often chosen at home. Available food appliances in trucks appeared to be associated with food choice patterns. Interestingly, food choice patterns and food preparation did not differ significantly across weight categories. CONCLUSIONS: The working conditions of professional truck drivers make a healthy lifestyle difficult to follow and appear to influence food choices while working. Particular effort should be taken to improve food choice patterns, food preparation and purchasing possibilities during trips.