Feasibility of a modern video-based technology for assessing the reaction time during specific karate kumite situations

Intraocular pressure responses to a virtual reality shooting simulation in active-duty members of the Spanish Army: The influence of task complexity

Ocular physiology is sensitive to cognitively demanding tasks. However, it is unknown whether the intraocular pressure is also affected by the cognitive demands of military operations. The main objective was to determine the impact of a virtual reality shooting simulation with two levels of complexity on intraocular pressure levels in military personnel. Eighteen active-duty members of the Spanish Army and eighteen civilians performed two 4 min simulated shooting tasks with two levels of complexity using a virtual reality. In the "easy" task participants performed a simulated shoot when the stimulus (military with a rifle) appeared, while in the "difficult" task the stimulus randomly was a military with a rifle or with his hands on the air and participants were instructed to respond only when the military with a rifle appeared. Intraocular pressure was measured with a rebound tonometer before and immediately after each task. Complementarily, perceived levels of mental load and shooting performance (reaction time) were assessed. Intraocular pressure was greater after completing the more complex task in both military personnel (p-value < 0.01, Cohen´s d = 1.19) and civilians (p-value < 0.01, Cohen´s d = 1.16). Also, perceived levels of task load and reaction time were higher in the difficult compared to the easy shooting tasks (both p < 0.001). The rise in intraocular pressure is positively associated with the cognitive demands of simulated military operations. The potential application of this finding is the development of objective tools based on intraocular pressure for the evaluation of the mental state in real-world contexts, permitting to improve soldiers´ safety and performance.

Association of military-specific reaction time performance with physical fitness and visual skills

Background

The aim of the present study was to explore whether military-specific reaction time (RT) test performance is affected by individuals' physical and visual skills.

Method

In a single testing session, the military-specific Simple and Go, No-Go RT, aerobic power (20-m Multistage Shuttle Run test), maximal upper- and lower-body mechanical capacities (bench press and squat against different loads), and visual skills (multiple object tracking and dynamic visual acuity) of 30 young men (15 active-duty military personnel and 15 sport science students) were evaluated.

Results

The main findings revealed that the Simple RT and Go, No-Go RT presented (1) with aerobic power non-significant small correlations in military personnel (r = -0.39 and -0.35, respectively) and non-significant negligible correlations in sport science students (r = -0.10 and 0.06, respectively), (2) inconsistent and generally non-significant correlations with the maximal mechanical capacities of the upper- and lower-body muscles (r range = -0.10, 0.67 and -0.27, 0.48, respectively), (3) non-significant correlations with visual skills (r magnitude ≥ 0.58) with the only exception of the Go, No-Go RT that was significantly correlated to all visual variables in the group of students (i.e., students who achieved better results during visual tests had shorter RT; r magnitude ≥ 0.58), and (4) none of the physical and visual variables significantly predicted the Simple RT or Go, No-Go RT.

Conclusion

Altogether, these results indicate that military-specific RT performance is generally independent of physical and visual skills in both military personnel and active university students.

Feasibility of Volitional Reaction Time Tests in Athletes: A Systematic Review

This systematic review aimed to synthesize the current evidence on the feasibility of volitional reaction time (RT) tests to evaluate the information processing abilities of athletes. Four databases were searched, and, finally, 38 studies exploring the reliability, validity, or sensitivity of RT tests were included. Seven studies explored the reliability, which ranged from poor to excellent, while only three studies explored the validity of RT tests. The most important downside of the majority of the implemented RT tests is their nonspecific nature (i.e., stimulus and response did not resemble the sports actions). Sports scientists should focus on developing RT tests that are specific for each sport and refine the testing procedures to obtain accurate, reproducible, and sensitive measurements of RT.

Reliability and Sensitivity of Reaction Time Measurements During Quasi-Realistic Soccer Situations

Reliability and sensitivity of reaction time (RT) during quasi-realistic soccer situations was explored in 10 professional soccer players (skilled; age = 20.9 ± 3.6 years) and 10 males without soccer experience (nonskilled; age = 23.4 ± 0.5 years). The participants were instructed to react as fast as possible to a stimulus presented via the video-based method while standing on force platforms. RT was computed as the difference between the instant when the rate of force development of any leg reaches 5% of its maximal value and the instant of stimulus presentation. The results revealed acceptable to high reliability of RT (intraclass correlation coefficient median = .90; coefficient of variation ≤ 5.83%), and shorter RT for skilled compared with nonskilled participants in three out of eight comparisons (effect size range = 1.00-1.41). The video-based methods can be confidently used to assess the RT in soccer players.