Initial evaluation of N,N-diethyl-m-toluamide and permethrin absorption in human volunteers under stress conditions.

Objectives: This was a pilot study to determine (1) whether it is feasible to effectively blind human subjects to the presence of the insect repellents N,N-diethyl-m-toluamide (DEET) and permethrin; (2) whether DEET affects the absorption of permethrin; and (3) whether combat videotape viewing and mental arithmetic are stressful.

Methods: Ten volunteers were exposed to DEET, permethrin, and stress (1-hour combat videotape plus mental arithmetic) in a double-blind, randomized, placebo-controlled trial. Outcome measurements included hemodynamics, plasma DEET and permethrin levels, and questionnaires to assess blinding.

Health assessment of U.S. Army Rangers.

Purpose: Assess the health behaviors of U.S. Army Rangers, including their diet and physical activity patterns, and their use of alcohol, tobacco, and nutritional supplements.

Choline ingestion does not modify physical or cognitive performance.

Objectives: This study was undertaken to determine whether choline ingestion improves physical and cognitive performance following exhaustive load carriage exercise.

Methods: In a double-blind crossover study, 13 men (28 +/- 2 years) underwent four test sessions: load carriage treadmill and no-load carriage test sessions after taking choline or placebo. Physical and cognitive performance batteries were administered at the end of the test sessions.