Release time: 2020-10-20 10:29

More Proof That Vigorous Workouts Boost Fluid Intelligence

Another new study reports that exercise regimens can improve fluid intelligence.

Last month, researchers from Colorado State University and the University of Illinois at Urbana-Champaign published a study (Burzynska et al. 2020) showing moderate-to-vigorous physical activity (MVPA) is positively correlated with improved fluid intelligence abilities. In contrast, sedentariness appears to facilitate better cognitive abilities relating to crystallized knowledge. Arthur Kramer, formerly of UIUC's Beckman Institute for Advanced Science and Technology, was this study's senior author. (See "Moderate-to-Vigorous Exercise May Benefit Fluid Intelligence.")

Today, another new study (Zwilling et al., 2020) was published in Scientific Reports that corroborates the link between vigorous workouts and better fluid intelligence abilities. Aron Barbey, a psychology professor at the University of Illinois at Urbana-Champaign and director of Beckman's Decision Neuroscience Laboratory, led the research team along with postdoctoral researcher and first author Christopher Zwilling.

For this 12-week, double-blind controlled clinical trial, the researchers recruited 148 active-duty Air Force airmen who were randomly assigned to two different groups in an experiment designed to see how effectively a multimodal physical fitness regimen alone—or in conjunction with a nutritional intervention—enhanced physical and cognitive performance.

All of the Air Force airmen (N = 148) participated in a 12-week exercise program that combined strength training gym workouts and high-intensity interval training (HIIT) cardio workouts. Notably, after just three months, the researchers found that, on average, fluid intelligence scores increased by 19.5 percent after kick-starting this exercise regimen.

Twice a day during this period, one group (n = 70) of airmen also drank a specially designed nutritional beverage that has been shown to boost cognitive functions in previous studies. This nutrient-enriched beverage contained vitamin B12, an omega-3 fatty acid (DHA), lutein, phospholipids, hydroxymethyl butyrate (HMB), and selected micronutrients, including folic acid.

The other cohort of airmen (n = 78), who represented a placebo control group, consumed a twice-daily beverage that was not enriched with nutrients. Neither the study participants nor the field researchers knew which group received the nutrient-enriched drink or a placebo beverage.

Chris Zwilling and colleagues also administered a battery of cognitive tests before and after the 12-week intervention to assess how the exercise regimen affected cognition by itself and in conjunction with the novel nutritional supplement. Six cognitive function domains were measured:

1\ episodic memory

2\ short-term memory

3\ working memory

4\ executive function

5\ fluid intelligence

6\ processing efficiency/reaction time

"Both groups improved in physical and cognitive function, with added gains among those who regularly consumed the nutritional beverage," the researchers stated in an October 19 news release.

As expected, the 12-week exercise regimen of strength training and HIIT workouts increased physical power and lean muscle mass, reduced participants' body fat percentages, and boosted their VO2 max. As mentioned, the most notable exercise-related gains in cognitive function were on tests designed to measure fluid intelligence.

After 12 weeks of HIIT and strength training exercise regimen, these are the "enhanced physical and cognitive performance in active duty airmen" results from the latest (2020) Zwilling et al. study: 

"The exercise intervention alone improved several dimensions of physical fitness [strength and endurance (+ 8.3 percent) power (+ 0.85 percent) mobility and stability (+ 22 percent) heart rate (− 1.1 percent) and lean muscle mass (+ 1.4 percent)] and cognitive function [(episodic memory (+ 9.5 percent) processing efficiency (+ 7.5 percent) executive function reaction time (− 4.8 percent) and fluid intelligence accuracy (+ 19.5 percent)]."

Interestingly, the researchers found that participants who consumed the nutrient-enriched beverage twice a day in addition to performing the exercise regimen "saw greater improvements in their ability to retain and process information. And their reaction time on tests of fluid intelligence improved more than their peers who took the placebo."

"The exercise intervention alone improved strength and endurance, mobility and stability, and participants also saw increases in several measures of cognitive function," Barbey explains in the news release. "They had better episodic memory and processed information more efficiently at the end of the 12 weeks. And they did better on tests that required them to solve problems they had never encountered before; an aptitude called fluid intelligence."

"Our work motivates the design of novel multimodal interventions that incorporate both aerobic fitness training and nutritional supplementation, and illustrates that their benefits extend beyond improvements in physical fitness to enhance multiple measures of cognitive function," Barbey concluded.

Christopher Bergland is a world-class endurance athlete, coach, author, and political activist.

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