Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
. 2012 Jul;222(2):337-42.
doi: 10.1007/s00213-012-2647-7.

Effects of coffee on driving performance during prolonged simulated highway driving

M A J Mets  1 , D Baas, I van Boven, B Olivier, J C Verster
Affiliations
Randomized Controlled Trial

Effects of coffee on driving performance during prolonged simulated highway driving

M A J Mets et al. Psychopharmacology (Berl). 2012 Jul.

Abstract

Rationale: Coffee is often consumed to counteract driver sleepiness. There is limited information on the effects of a single low dose of coffee on prolonged highway driving in non-sleep deprived individuals.

Objectives: The aim of this study was to examine the effects of a single cup of coffee (80 mg caffeine) on simulated highway driving performance.

Methods: Non-sleep deprived healthy volunteers (n024) participated in a double-blind, placebo-controlled, crossover study. After 2 h of monotonous highway driving, subjects received caffeinated or decaffeinated coffee during a 15-min break before continuing driving for another 2 h. The primary outcome measure was the standard deviation of lateral position (SDLP), reflecting the weaving of the car. Secondary outcome measures were speed variability, subjective sleepiness, and subjective driving performance.

Results: The results showed that caffeinated coffee significantly reduced SDLP as compared to decaffeinated coffee, both in the first (p00.024) and second hour (p00.019) after the break. Similarly, the standard deviation of speed (p0 0.024; p00.001), mental effort (p00.003; p00.023), and subjective sleepiness (p00.001; p00.002) were reduced in both the first and second hour after consuming caffeinated coffee. Subjective driving quality was significantly improved in the first hour after consuming caffeinated coffee (p00.004).

Conclusions: These findings demonstrate a positive effect of one cup of caffeinated coffee on driving performance and subjective sleepiness during monotonous simulated highway driving.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Standard deviation of lateral position (SDLP). Asterisks indicate significant difference compared to placebo (p < 0.05)
Fig. 2
Fig. 2
Standard deviation of speed (SDS). Asterisks indicate significant difference compared to placebo (p < 0.05)
Fig. 3
Fig. 3
Karolinska sleepiness scale. Asterisks indicate significant difference compared to placebo (p < 0.05)
See this image and copyright information in PMC

References

    1. Åkerstedt T, Gillberg M. Subjective and objective sleepiness in the active individual. Int J Neurosci. 1990;52:29–37. doi: 10.3109/00207459008994241. - DOI - PubMed
    1. Anund A, Kecklund G, Peters B, Åkerstedt T. Driver sleepiness and individual differences in preferences for countermeasures. J Sleep Res. 2008;17:16–22. doi: 10.1111/j.1365-2869.2008.00633.x. - DOI - PubMed
    1. Arnaud MJ. The pharmacology of caffeine. Prog Drug Res. 1987;31:273–313. - PubMed
    1. Biggs SN, Smith A, Dorrian J, Reid K, Dawson D, Van den Heuvel C, Baulk S. Perception of simulated driving performance after sleep restriction and caffeine. J Psychosom Res. 2007;63:573–577. doi: 10.1016/j.jpsychores.2007.06.017. - DOI - PubMed
    1. Blanchard J, Sawers SJA. The absolute bioavailability of caffeine in man. Eur J Clin Pharmacol. 1983;24:93–98. doi: 10.1007/BF00613933. - DOI - PubMed

Publication types