Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Aviat Space Environ Med. 2007 Sep;78(9):871-7.

Caffeine effects on physical and cognitive performance during sustained operations.

Author information

  • 1Individual Readiness Section, DRDC-Toronto, 1133 Sheppard Avenue West, PO Box 2000, Toronto, Ontario M3M 3B9, Canada. tom.mclellan@drdc-rddc.gc.ca

Abstract

PURPOSE:

This study examined caffeine (CAF) effects on physical performance and vigilance during 4 d and 3 nights of sustained operations in Special Forces personnel.

METHODS:

There were 20 soldiers (28.6 +/- 4.7 yr, 177.6 +/- 7.5 cm, 81.2 +/- 8.0 kg) who were divided equally into placebo (PLAC) and CAF groups. A 4-km run that included three obstacles (OBST) was completed each morning with the performance on Day 2 representing control (CON) after familiarization on Day 1 and an 8-h sleep. From 01:30 to 06:15 of Days 3-5, soldiers performed two 2-h vigilance (VIG) sessions in the field. PLAC or 200 mg of CAF was administered at 21:45 of Days 2-4 and at 01:00, 03:45, and approximately 07:00 on Days 3-5. The run commenced within 30 min of the final dose. Soldiers were provided a 4-h sleep period from 13:30-17:30 during Days 3 and 4.

RESULTS:

VIC during Days 3-5 was greater for CAF vs. PLAC and not different from CON. Total run time was faster for CAF (29.7 +/- 2.0 min) compared with PLAC (30.7 +/- 2.9 min) on Day 3 due to faster completion of OBST (8.7 +/- 0.7 min vs. 9.2 +/- 1.0 min for CAF and PLAC, respectively). Thereafter, run times decreased for both groups on Days 4 and 5 compared with CON due primarily to an increased pace between OBST.

CONCLUSIONS:

it was concluded that CAF maintained both vigilance and physical performance during sustained operations that require periods of overnight wakefulness and restricted opportunities for daytime sleep.

PMID:
17891897
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Ingenta plc
    Loading ...
    Write to the Help Desk