Can Exercise Affect Your IQ Score?

Does working out actually make you smarter? Discover how exercise impacts your IQ score and cognitive performance. Read our guide and try the RIOT test!

Dr. Russell T. WarneChief Scientist

The relationship between physical exercise and cognitive performance is one of the more robustly supported findings in behavioral neuroscience, and one of the most consistently misrepresented in popular media. The answer to whether exercise can affect your IQ score is yes, but the mechanism, the magnitude, the timeline, and the specific cognitive domains involved all matter enormously. This article breaks down what the research actually shows, where it's solid, and where its impact on your IQ test results remains genuinely uncertain.

Two Different Questions That Often Get Conflated

Before getting into the evidence, it's worth separating two distinct questions that the popular discussion tends to blend together.

The first is whether acute exercise or a single bout of physical activity can temporarily improve performance on cognitive tasks, including tasks that appear on IQ tests. The second is whether regular, long-term exercise produces durable improvements in cognitive ability that would show up as a meaningfully higher IQ score weeks or months later.

The answer to the first question is fairly clear: yes, with meaningful effect sizes on specific domains. The answer to the second is more complicated — the evidence for sustained structural cognitive gains exists, but the magnitude is more modest and the effect is not uniform across all cognitive domains.

What Happens Immediately After Exercise

The acute cognitive effects of exercise are well-documented. A 2025 study of 121 participants randomly assigned to a moderate-intensity resistance exercise session or rest found that acute resistance exercise produced faster processing speed during inhibitory control (effect size d = 0.37) and improved working memory performance (d = 0.46), with corresponding reductions in P3 latency on EEG indicating faster neural processing. These effects were observed immediately following the exercise session.

A study examining time-dependent effects of acute aerobic exercise found that reaction times on processing speed and working memory tasks decreased significantly immediately after 30 minutes of moderate-intensity treadmill running, with working memory improvements persisting 30 minutes post-exercise in temperate conditions. These are not trivial effects — in psychometric terms, effect sizes in the 0.35–0.50 range are meaningful enough to shift performance on individual subtests.

The mechanism behind these acute effects is reasonably well understood. Exercise increases cerebral blood flow and raises circulating levels of neurotransmitters including dopamine, norepinephrine, and serotonin, all of which support attentional control and working memory. It also elevates brain-derived neurotrophic factor (BDNF), a protein that supports synaptic plasticity and neuronal communication. These effects are transient but real, which raises an interesting practical implication: if you take an IQ test shortly after moderate exercise, your performance on processing speed and working memory subtests may be genuinely better than if you took it after a sedentary morning.

What Long-Term Exercise Does to the Brain

The structural evidence for long-term exercise effects on cognition is where the science becomes particularly compelling. Aerobic exercise is well-established for its beneficial effects on cognitive performance through its impact on adult hippocampal neurogenesis — the growth of new neurons in the hippocampus, a region central to memory consolidation and spatial navigation. BDNF is the primary molecular mediator of this effect, stimulating neural stem cell proliferation, neuronal survival, and synaptic plasticity in the hippocampal dentate gyrus.

What this means practically is that regular aerobic exercise appears to do something that most other behavioral interventions cannot: it physically changes the structure of a brain region directly involved in learning and memory. Numerous studies have documented enduring neurological alterations resulting from aerobic exercise training that are strongly correlated with observed enhancements in cognitive performance, particularly in long-term modifications within the hippocampus.

A 2025 Bayesian network meta-analysis of 15 randomized controlled trials involving 3,400 participants aged 5–18 found that exercise was linked to small-to-moderate improvements in general intelligence (SMD = 0.59), fluid intelligence (SMD = 0.43), and crystallized intelligence (SMD = 0.64). Dual-task balance training produced the most consistent and significant benefits across all three domains. These are meaningful effect sizes — particularly the fluid intelligence finding, since fluid reasoning is widely considered the cognitive domain most resistant to environmental manipulation.

A separate 2025 meta-analysis of physical exercise interventions in adolescents found that exercise produced significant positive effects on executive function, attention, working memory, cognitive flexibility, and inhibitory control, with the largest effects observed for aerobic exercise modalities. Network meta-analysis further found that dance demonstrated the highest ranking for improving working memory accuracy (SMD = 0.67), outperforming standard aerobic exercise, HIIT, and mixed modalities on that specific domain.

The IQ-Specific Question

Here's where I want to be precise, because the evidence above doesn't automatically translate into "exercise raises your IQ score" in the way that headline-friendly summaries sometimes suggest.

The cognitive domains most reliably improved by exercise — working memory, processing speed, executive function, and attentional control — are exactly the domains that IQ tests partially measure. The RIOT measures six cognitive indices including processing speed and working memory; the WAIS measures similar domains. So if exercise produces genuine, measurable improvements in those capacities, those improvements would show up on a well-constructed IQ battery.

The question is magnitude. Most of the effect sizes in the literature, while statistically significant and meaningful in clinical or educational contexts, translate into relatively modest IQ point gains — typically in the range of 3 to 7 points under the most favorable conditions (sustained aerobic exercise over months, in populations with low baseline fitness). That's a real effect, but it's not the dramatic IQ transformation that some popular accounts imply. And it's worth noting that the 2025 meta-analysis finding SMD = 0.59 for general intelligence in children represents the upper end of the literature — adult populations typically show smaller effects, particularly on measures of fluid reasoning.

The modality also matters considerably. Aerobic exercise consistently shows the strongest effects on hippocampal-dependent memory and fluid reasoning. Resistance exercise shows stronger acute effects on processing speed and executive function but less consistent long-term structural impact on the hippocampus. Combined exercise programs show variable results depending on the sequencing and intensity — notably, research in rats found that strength exercise weakened aerobic exercise-induced cognitive improvements and hippocampal neurogenesis in an intensity-dependent manner, suggesting that the combination isn't automatically additive.

What This Means Before You Take an IQ Test

The acute exercise literature has a direct practical implication that most test-preparation guides don't mention: moderate aerobic exercise in the 24–48 hours before an IQ assessment, and potentially even a light 20–30 minute session on the morning of the test, is likely to produce a small but measurable boost in processing speed and working memory performance relative to a sedentary comparison condition.

This isn't gaming the test — it's optimizing your physiological state, which is no different in principle from getting adequate sleep or eating before testing. What it doesn't do is change your fluid reasoning capacity or your crystallized knowledge base. The cognitive domains that exercise most acutely benefits — processing speed and working memory — are real components of a full cognitive profile, but they're not the only ones.

The flip side also matters: taking an IQ test in a state of physical exhaustion from intense exercise the day before — when DOMS, fatigue, and disrupted sleep may all be factors — is likely to suppress performance below your actual level. The optimal preparation window for the acute benefit is moderate-intensity exercise roughly 20–60 minutes before testing, not high-intensity exercise the day before.

The Takeaway

Exercise does affect cognitive performance, and by extension, IQ test scores, but the relationship is nuanced. Acutely, moderate aerobic and resistance exercise reliably improves processing speed and working memory within minutes to hours of the session, with effect sizes large enough to be practically meaningful on individual subtests. Long-term, sustained aerobic exercise produces structural brain changes — particularly hippocampal neurogenesis via BDNF — that support genuine improvements in memory, executive function, and, in some populations, fluid reasoning. The magnitude of the long-term IQ effect is real but modest, typically in the 3–7 point range under favorable conditions.

The most evidence-based takeaway is also the least surprising: exercise is one of the highest-leverage behavioral investments you can make for cognitive health across the lifespan — not because it turns you into a different thinker, but because it consistently supports the brain systems that underlie the cognitive capacities that IQ tests are built to measure.

If you want to see your current cognitive profile across all the domains that exercise most directly affects — processing speed, working memory, and fluid reasoning — the RIOT gives you a precise, domain-level picture rather than a single number.

References

PubMed Central. (2025). Brawn and Brainpower: Acute Resistance Exercise Improves Behavioral and Neuroelectric Measures of Executive Function. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12575885/
PubMed Central. (2017). Time-Dependent Effects of Acute Exercise on University Students' Cognitive Performance. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5506219/
PubMed Central. (2018). Strength exercise weakens aerobic exercise-induced cognitive improvements in rats. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179267/
PubMed Central. (2025). Optimal exercise modalities and dose for enhancing intelligence in children and adolescents: a Bayesian network meta-analysis. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12851973/
PubMed Central. (2025). The effects of physical exercise on cognitive function in adolescents: a systematic review and meta-analysis. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12337486/
PubMed Central. (2025). Effects of different long-term exercise interventions on working memory in children and adolescents: a network meta-analysis. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12019642/
PubMed Central. (2025). Aerobic Exercise Promotes Hippocampal Neurogenesis and Ameliorates Cognitive Dysfunction. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12865327/
PubMed Central. (2025). Effects of Exercise on Cognitive Function in People with Intellectual Disabilities: A Systematic Review and Meta-Analysis. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12651325/