Manousakis JE, et al. – This study was performed to investigate impairment and recovery of performance alongside decaying levels of alcohol, with and without sleep restriction. Findings revealed that falling breath alcohol concentrations [BrACs] were an inadequate guide for performance/safety and rest breaks without sleep were not a safety measure for mitigating performance impairment when consuming alcohol following restricted sleep.

Methods

• In the study presented here, 16 healthy young males (18–27 years) underwent 4 counterbalanced conditions: Baseline, Alcohol (breath alcohol concentration [BrAC] < 0.05%), Sleep Restriction (5 hr time in bed), and Combined.
• Members consumed alcohol (or control drink) ~4.5 hr post wake (12:30 p.m.).
• Attention and vigilance test batteries commenced 1 hr after consumption and were completed every 30 min for 2 hr (1:30 p.m.–3:30 p.m.) to test on the descending limb of alcohol.

Results

• Researchers reported that the Combined condition impaired subjective and objective sleepiness.
• They observed that performance deficits peaked 90 min after alcohol consumption or 30 min after the BrAC peak.
• They noted that performance did not return to baseline levels until 2.5 hr following consumption, despite receiving rest breaks in between testing.