DVIDS – News – Helping soldiers train their brains and bodies to improve endurance

Soldiers have long known that a disciplined exercise regimen can improve their physical strength. Researchers at the U.S. Army Medical Research and Development Command’s Walter Reed Army Institute of Research are now investigating ways to augment physical exercise with “brain exercises” that could potentially help military members improve their performance under conditions of stress and fatigue.

“We’re not saying that cognitive training can make you smarter,” says Dr. Brad Fawver, research scientist at WRAIR’s US Army Medical Research Directorate-West. “But it’s well established that we tend to be better at the things we train on and worse at the things we ignore.”

Building on the pioneering work of director USAMRD-Wa regiment. Michael Dretsch, Ph.D., Fawver leads the Brain-Physical Optimization Conditioning research program. With financial support from USAMRDC’s Military Operational Medicine Research Program, B-POC is evaluating new strategies for building military members’ resilience through mind-body training and other integrated interventions. One approach the team is testing uses brain endurance training, or BET, which involves performing mentally demanding tasks (say, recalling a specific sequence or sequence of shapes, symbols, and colors) before, during, or after strenuous physical exercise. Fawver and other researchers believe that this inclusion of mental fatigue in addition to physical fatigue changes the brain’s tolerance to exhaustion.

This is important because published reports show that muscle and joint fatigue is preceded by perceptions of effort originating in the brain, which determine how long a person is willing to push themselves before shutting down—often too soon. Mental fatigue also negatively affects a wide range of physical and technical skills including exercise, sports, driving and flying. Research has shown that people who include BET in their aerobic training experience improved physical performance results and also that BET appears to cause functional changes in parts of the brain associated with the perception of demand, effort and fatigue.

Fawver provided an overview of the B-POC program’s recent achievements at the 2023 Military Health System Research Symposium on August 17, 2023. In their first series of tests, a group of volunteer service members participated in a six-week training program in which half of the volunteers performed a low-level memory task. to moderate demand while they ran on a treadmill for 45 minutes, while the other half performed a memory task with almost no demands while doing the same exercise. Each participant received comprehensive pre- and post-training assessments that included an endurance test, a battery of cognitive tests while fatigued, and a dynamic marksmanship test before and after the ruck march.

Fawver’s team found that volunteers who were given low-to-moderate memory tasks during training showed a twofold improvement in endurance performance and twice as much effort perception compared to a control group after six weeks of training.

“We designed this first study to be quite simple, as a way to reduce the number of variables while expanding the science,” explains Fawver. “But we were shocked by the results. Some very physically fit soldiers ran 5 to 15 minutes longer in a test they had previously failed completely just six weeks before. This gives us the confidence to assess more complex and challenging training approaches.”

The team at USAMRD-W is currently investigating the utility of this approach with high-intensity interval and circuit exercises, both of which are better aligned with the current Army Combat Fitness Test. With the help of stakeholders such as the Army’s Holistic Health and Fitness Program, the team will be able to identify other potential applications. They are also interested in the benefits of operational training tasks, psychological skill development, and even neurostimulation during physical training. One project will stimulate participants’ vagus nerve during exercise rest periods to improve their cognitive functioning.

Many questions remain about how to optimize these training approaches, including whether some changes last longer than a few weeks.

“I wish I could tell you we have all the answers,” Fawver says, “but we’re starting to narrow down the underlying neural mechanisms and apply that knowledge to the ‘gamification’ of training systems.”

To support their research, the USAMRD-W team developed international partnerships with the Brazilian Army’s Physical Fitness Research Institute and the Norwegian Arctic University to evaluate this training approach in combination with a series of strenuous physical exercises in extreme climates. Future research and development will also examine individual differences in tolerance and identify other psychological and physiological processes that contribute to the effectiveness of BET.

“Many people think of psychological resilience as something extra beyond the physical body, a tool you have to reach into your bag and get,” says Fawver. “But the best form of resilience is not resource-consuming per se; it is implicit and integrated, and becomes part of your operational skill set. This kind of training will produce Warfighters who are much more resilient to things like anxiety, physical stress and all those other operational demands placed on them in deployed environments.”

Ultimately, the USAMRD-W team aims to see these cognitive training tools tailored to an individual’s personal health and fitness goals. The inclusion of performance feedback or other incentives could be included to improve engagement, such as competition with family, friends, co-workers or ranking the best in their local installation. As Fawver points out, almost everyone has a wearable device, cell phone or tablet that they can use to exercise their brain while exercising.

“This is where the fun begins, because you’re finally starting to see more studies confirming the effects of these integrated interventions,” says Fawver. “We’re excited about where this research will take us, but the challenge is to create something truly innovative and impactful for the brain health and performance of service members. They will always be our main focus.”