The Effects of a Combination of TeaCrine®, Dynamine, and Caffeine on Marksmanship Accuracy and Reaction Time in ROTC Members, Military, and Law Enforcement Following a Mentally Fatiguing Protocol

BASELINE ASSESSMENT:

• Subjects will report to the University of South Carolina Sport Science Lab normally hydrated and having refrained from eating for minimum 2 hours prior.
• Upon arrival, subjects will complete the informed consent and the Caffeine Frequency Questionnaire (CFQ) to assess their intake.
• Subjects will have body composition assessed using air displacement plethysmography (Bod Pod, Cosmed, Inc.) using standardized procedures.
• A salivary sample will be provided by each subject before beginning familiarization to analyze for presence of the CYP1A2 (caffeine) gene.
• Subjects will be familiarized with the cognitive testing protocols using the Dynavision D2TM board and TRAZER Sports Simulator. They will complete a shortened version of the mentally fatiguing condition on the DynavisionTM to familiarize with the protocol. They will be able to complete 3 trials of reaction time using the simulation on the TRAZER.
• Following this, subjects will then complete 3 trials of marksmanship assessment using the optical targetry system.

CONDITIONS:

• Following exercise familiarization, subjects will be randomly assigned to the condition of placebo (P), caffeine (C), or combination of caffeine + TeaCrine + Dynamine (DC). Sessions will be scheduled at the same time as the initial baseline/familiarization session.
• Subjects will be asked to maintain a normal sleep schedule in the week leading up to their session, maintaining the same wake time each day.
• Subjects will be asked to refrain from alcohol for 48 hours and caffeine 24 hours prior to their condition, with no major changes in food intake.
• Subjects will consume the supplement, complete the Multi-Component Training Distress Scale (MTDS) and will begin their session 30 minutes later.
• Sessions will include 30 minutes of a mentally fatiguing task on the Dynavision D2TM board, designed with a go/no-go stimulus. The blinds will be drawn and lights switched off to reduce glare on the board.
• At baseline and after each phase of the protocol, an assessment of psychological arousal will be taken using subjective measures of the Felt Arousal Scale (FAS) .
• Subjects will then perform the reaction time assessment on the TRAZER and shooting assessment. This will be performed twice. The TRAZER will consist of 40 targets, and the shooting assessment will be 8 shots with a tactical re-load followed by an additional 8 shots. A 2-minute rest will be taken between trials. Total time allotted for assessments will be 20 minutes.
• Subjects will then be seated in a room for 30 minutes, during which time they will read leisurely. At the completion of this time, subjects will complete the mentally fatiguing protocol once more (30 minutes). Following this, measures of reaction time and shooting assessment will be performed again (20 minutes).
• Heart rate will be monitored and recorded throughout testing to establish average and peak values during the reaction time and marksmanship tasks.
• Blood pressure will be measured pre- and post-testing using the Omron HEM 907XL Intellisense Pro Digital Blood Pressure cuff.