Exercise and Brain Health: Proven Cognitive Benefits

As a functional nutrition therapy practitioner and nootropics expert, I’m often asked if simple lifestyle measures like exercise can really make a difference for brain health and function. You may be surprised to discover that physical activity provides incredible cognitive gains that often rival pharmaceutical options. ¹Erickson KI, Hillman CH, Stillman CM, et al. Physical activity, cognition, and brain outcomes: a review of the 2018 physical activity guidelines. Med Sci Sports Exerc. 2019;51(12):2442-2451. doi:10.1249/MSS.0000000000002116 https://pubmed.ncbi.nlm.nih.gov/31095081/ and ²Stillman CM, Cohen J, Lehman ME, Erickson KI. Mediators of physical activity on neurocognitive function: A review at multiple levels of analysis. Front Hum Neurosci. 2016;10:626. Published 2016 Dec 6. doi:10.3389/fnhum.2016.00626 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5161022/ can further amplify the nootropic power of fitness.

In this article, we’ll break down the science explaining how exercise benefits the brain. I’ll also provide my top tips to optimize your workouts for maximum mental gains.

Let’s dive into unlocking your brain’s full potential through exercise!

How Does Exercise Impact Brain Power?

Physical activity boosts blood flow, stimulates neuron growth, and activates key pathways for improved function. Here are some of the key mechanisms for fitness-fueled cognitive gains:

1. Boosts Brain Plasticity

Your brain’s plasticity is its ability to form new neuronal connections and pathways. The more plastic your brain, the easier it is to learn, memorize, and adapt ³Firth J, Stubbs B, Vancampfort D, et al. Effect of aerobic exercise on hippocampal volume in humans: A systematic review and meta-analysis. Neuroimage. 2020;116906. doi:10.1016/j.neuroimage.2020.116906 https://pubmed.ncbi.nlm.nih.gov/29113943/.

Research confirms that exercise ramps up plasticity, especially in memory centers like the hippocampus ⁴Erickson KI, Hillman CH, Stillman CM, et al. Physical activity, cognition, and brain outcomes: a review of the 2018 physical activity guidelines. Med Sci Sports Exerc. 2019;51(12):2442-2451. doi:10.1249/MSS.0000000000002116 https://pubmed.ncbi.nlm.nih.gov/31095081/.

In animal trials, just three weeks of running doubled nerve cell growth in the hippocampus. Human data also shows aerobic activity leads to significant structural changes, including enhanced connectivity ⁵Burzynska AZ, Chaddock-Heyman L, Voss MW, et al. Physical activity and cardiorespiratory fitness are beneficial for white matter in low-fit older adults. PLoS One. 2014;9(9):e107413. Published 2014 Sep 15. doi:10.1371/journal.pone.0107413 https://pubmed.ncbi.nlm.nih.gov/25229455/.

Read more: 11 Best Supplements For Neuroplasticity

2. Stimulates Brain-Derived Neurotrophic Factor (BDNF)

Think of BDNF as the “miracle grow” fertilizer for your brain. This powerful protein repairs neurons stimulate growth and forms new connections ⁶Szuhany KL, Bugatti M, Otto MW. A meta-analytic review of the effects of exercise on brain-derived neurotrophic factor. J Psychiatr Res. 2015;60:56-64. doi:10.1016/j.jpsychires.2014.10.003 https://pubmed.ncbi.nlm.nih.gov/25455510/.

Research confirms fitness ramps up BDNF across brain regions critical for learning and memory, like the cortex and hippocampus ⁷Griffin ÉW, Mullally S, Foley C, Warmington SA, O’Mara SM, Kelly ÁM. Aerobic exercise improves hippocampal function and increases BDNF in the serum of young adult males. Physiol Behav. 2011;104(5):934-941. doi:10.1016/j.physbeh.2011.06.005 https://pubmed.ncbi.nlm.nih.gov/21722657/.

Animal data shows exercise doubles BDNF gene expression ⁸Berchtold NC, Castello N, Cotman CW. Exercise and time-dependent benefits to learning and memory. Neuroscience. 2010;167(3):588-597. doi:10.1016/j.neuroscience.2010.02.050 https://pubmed.ncbi.nlm.nih.gov/20219647/. The key memory center (hippocampus) also enlarges after aerobic training ⁹Liu PZ, Nusslock R. Exercise-mediated neurogenesis in the hippocampus via BDNF. Front Neurosci. 2018;12:52. Published 2018 Feb 13. doi:10.3389/fnins.2018.00052 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5808288/.

Clearly, moving your body provides some serious neuron-growing power!

3. Boosts Blood Flow to the Brain

As a nutritional therapy practitioner, I always emphasize optimizing delivery systems before sending in nutrients.

The same concept applies to our brain health. What good are neurons and BDNF if not properly nourished?

Luckily, research confirms that exercise significantly increases cerebral blood flow ¹⁰Sugawara J, Tomoto T, Repshas J, Zhang R, Tarumi T. Middle-aged endurance athletes exhibit lower cerebrovascular impedance than sedentary peers. J Appl Physiol (1985). 2020;129(2):335-342. doi:10.1152/japplphysiol.00239.2020. Published 2020 Jul 16. PMCID: PMC7473949. PMID: 32673159. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7473949/. This effect occurs acutely during activity and lasts hours after ¹¹Dennis A, Thomas AG, Rawlings NB, et al. An ultra-high field magnetic resonance spectroscopy study of post exercise lactate, glutamate and glutamine change in the human brain. Front Physiol. 2015;6:351. doi:10.3389/fphys.2015.00351. Published 2015 Dec 17. https://www.frontiersin.org/articles/10.3389/fphys.2015.00351/full.

The visual and memory centers of the brain (occipital and parahippocampal regions) experience the greatest gains ¹²Burdette JH, Laurienti PJ, Espeland MA, et al. Using network science to evaluate exercise-associated brain changes in older adults. Front Aging Neurosci. 2010;2:23. Published 2010 Jun 25. doi:10.3389/fnagi.2010.00023 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2893375/.

Read more: The 10 Best Nootropics For Creativity | Supplements, Biohacks, & More!

Proven Cognitive Gains from Fitness

Let’s move from mechanisms to real-world brainpower gains with some compelling research.

Enhanced Executive Function

The executive function, the crown jewel of cognitive skill, allows you to plan, memorize, problem-solve, and focus. Without it, you’d struggle with even basic daily tasks.

The good news? Numerous studies prove aerobic activity enhances executive function across all ages:

• Older women performed over 20% better on planning and scheduling tests after just 6 months of aerobic training ¹³Liu-Ambrose T, Nagamatsu LS, Graf P, Beattie BL, Ashe MC, Handy TC. Resistance training and executive functions: a 12-month randomized controlled trial. Arch Intern Med. 2010;170(2):170-178. doi:10.1001/archinternmed.2009.494 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3448565/.
• A 30-minute treadmill workout boosted young adults’ executive function by nearly 100% – similar gains from some powerful smart drugs! ¹⁴Winter B, Breitenstein C, Mooren FC, et al. High impact running improves learning. Neurobiol Learn Mem. 2007;87(4):597-609. doi:10.1016/j.nlm.2006.11.003 https://pubmed.ncbi.nlm.nih.gov/17185007/.

Clearly, both one-time aerobic bursts and chronic training pay exponential dividends for core brainpower.

Boosts Learning and Memory

A sharp memory helps us acquire and recall knowledge rapidly.

Once again, science confirms fitness fuels these key learning processes:

• Young women performed nearly 10% better on memory tests after 30 minutes of intense treadmill running ¹⁵Winter B, Breitenstein C, Mooren FC, et al. High impact running improves learning. Neurobiol Learn Mem. 2007;87(4):597-609. doi:10.1016/j.nlm.2006.11.003 https://pubmed.ncbi.nlm.nih.gov/17185007/.
• School-aged children had 12% higher reading scores and 10% higher math scores when they exercised just 45 minutes more per week ¹⁶Donnelly JE, Hillman CH, Castelli D, et al. Physical Activity, Fitness, Cognitive Function, and Academic Achievement in Children: A Systematic Review. Med Sci Sports Exerc. 2016;48(6):1197-1222. doi:10.1249/MSS.0000000000000901 https://pubmed.ncbi.nlm.nih.gov/27182986/.

Whether you’re a student cramming for exams or a professional absorbing critical job knowledge, exercise can clearly help you learn and remember more in less time.

Read more: Best Nootropics For Studying, Memory, and Focus

Top Tips to Optimize Workouts for Brain Gains

Now that you’ve seen how potent a nootropic fitness can be, let’s talk practical strategies to maximize these mental benefits.

Follow these tips at your next workout to take your brainpower to new heights!

1. Include High-Intensity Interval Training (HIIT)

Research confirms that HIIT style training increases BDNF and executive function more than moderate intensity ¹⁷Herold F, Törpel A, Schega L, Müller NG. Functional and structural brain alterations following high-intensity aerobic exercise. Sci Rep. 2019;9(1):8595. Published 2019 Jun 13. doi:10.1038/s41598-019-45184-x https://pubmed.ncbi.nlm.nih.gov/31333805/.

Our favorite HIIT protocols are:

• Tabata – 20 seconds maximal effort followed by 10 seconds rest, repeat eight times.
• Sprint intervals – 30 seconds as fast as possible, 90 seconds recovery, repeat five times.

Aim to include Tabata or sprints 1-2x per week in addition to regular training.

2. Layer Strength and Cardio

Most studies on exercise and cognition focus solely on aerobic training. However, science shows layered strength + cardio training provides more widespread cognitive gains ¹⁸Northey JM, Cherbuin N, Pumpa KL, Smee DJ, Rattray B. Exercise interventions for cognitive function in adults older than 50: a systematic review with meta-analysis. Br J Sports Med. 2018;52(3):154-160. doi:10.1136/bjsports-2016-096587 https://pubmed.ncbi.nlm.nih.gov/28438770/.

Try this blended workout structure:

• 5-10 minute warmup
• 30 minutes weights/resistance bands
• 20 minutes cardio
• 5-10 minute cooldown

This stimulates both aerobic and anaerobic pathways for maximum mental benefits.

3. Train Outdoors In Nature

If possible, conduct some of your workouts surrounded by natural settings. Studies show exercising in nature enhances memory, focus, and mood more than indoor training ¹⁹Berman MG, Jonides J, Kaplan S. The Cognitive Benefits of Interacting With Nature. Psychol Sci. 2008;19(12):1207-1212. doi:10.1111/j.1467-9280.2008.02225.x https://pubmed.ncbi.nlm.nih.gov/19121124/.

Factors like negative ions, reduced noise/crowds, increased oxygen, and microbes boost training’s cognitive effects.

So hike a local trail, grab your yoga mat for the park, or go for a peaceful country run. Just be sure to soak in the natural sights, sounds, and air to energize your workout and your brain!

4. Support with Nootropic Nutrition

You wouldn’t exercise without proper pre/post-fueling and hydration. Likewise, select nootropic supplements before and after workouts to amplify cognitive gains.

Key areas to support include plasticity, BDNF, blood flow, and bioenergetics pathways. Recommended products include:

• Mind Lab Pro – Citicoline reinforces neuron membranes.
• Microbiome Labs MegasporeBiotic – Repairs gut permeability
• Nootropics Depot ALCAR – Carnitine transports fats to fuel mitochondria
• Omni PEMF – Enhances post-workout recovery
• Performance Lab Mind – Marigold suppresses inflammatory cytokines
• Performance Lab Vitamin D + K2 – Vitamin D aids nutrient absorption
• Nootropics Depot Holy Basil – An adaptogen that combats exercise-induced stress
• Nootropics Depot Taurine – Stabilizes cellular fluid changes from training
• Zona Plus – Improves blood flow to enhance circulation
• NutriSense CGM – Monitors glucose levels to optimize carb intake
• Recess – Adaptogens reduce cortisol spikes
• Higher Dose Infrared PEMF Mat – Infrared therapy aids recovery

Time this nootropic nutrition 30-60 minutes pre and post-exercise for optimal absorption.

References

• Erickson KI, Hillman CH, Stillman CM, et al. Physical activity, cognition, and brain outcomes: a review of the 2018 physical activity guidelines. Med Sci Sports Exerc. 2019;51(12):2442-2451. doi:10.1249/MSS.0000000000002116 https://pubmed.ncbi.nlm.nih.gov/31095081/
• Firth J, Stubbs B, Vancampfort D, et al. Effect of aerobic exercise on hippocampal volume in humans: A systematic review and meta-analysis. Neuroimage. 2020;116906. doi:10.1016/j.neuroimage.2020.116906 https://pubmed.ncbi.nlm.nih.gov/29113943/
• Stillman CM, Cohen J, Lehman ME, Erickson KI. Mediators of physical activity on neurocognitive function: A review at multiple levels of analysis. Front Hum Neurosci. 2016;10:626. Published 2016 Dec 6. doi:10.3389/fnhum.2016.00626 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5161022/
• Szuhany KL, Bugatti M, Otto MW. A meta-analytic review of the effects of exercise on brain-derived neurotrophic factor. J Psychiatr Res. 2015;60:56-64. doi:10.1016/j.jpsychires.2014.10.003 https://pubmed.ncbi.nlm.nih.gov/25455510/
• Griffin ÉW, Mullally S, Foley C, Warmington SA, O’Mara SM, Kelly ÁM. Aerobic exercise improves hippocampal function and increases BDNF in the serum of young adult males. Physiol Behav. 2011;104(5):934-941. doi:10.1016/j.physbeh.2011.06.005 https://pubmed.ncbi.nlm.nih.gov/21722657/
• Berchtold NC, Castello N, Cotman CW. Exercise and time-dependent benefits to learning and memory. Neuroscience. 2010;167(3):588-597. doi:10.1016/j.neuroscience.2010.02.050 https://pubmed.ncbi.nlm.nih.gov/20219647/
• Sugawara J, Tomoto T, Repshas J, Zhang R, Tarumi T. Middle-aged endurance athletes exhibit lower cerebrovascular impedance than sedentary peers. J Appl Physiol (1985). 2020;129(2):335-342. doi:10.1152/japplphysiol.00239.2020. Published 2020 Jul 16. PMCID: PMC7473949. PMID: 32673159. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7473949/
• Dennis A, Thomas AG, Rawlings NB, et al. An ultra-high field magnetic resonance spectroscopy study of post exercise lactate, glutamate and glutamine change in the human brain. Front Physiol. 2015;6:351. doi:10.3389/fphys.2015.00351. Published 2015 Dec 17. https://www.frontiersin.org/articles/10.3389/fphys.2015.00351/full
• Kempermann G, Fabel K, Ehninger D, et al. Why and how physical activity promotes experience-induced brain plasticity. Front Neurosci. 2010;4:189. doi:10.3389/fnins.2010.00189 https://pubmed.ncbi.nlm.nih.gov/21151782/
• Burdette JH, Laurienti PJ, Espeland MA, et al. Using network science to evaluate exercise-associated brain changes in older adults. Front Aging Neurosci. 2010;2:23. Published 2010 Jun 25. doi:10.3389/fnagi.2010.00023 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2893375/
• Liu PZ, Nusslock R. Exercise-mediated neurogenesis in the hippocampus via BDNF. Front Neurosci. 2018;12:52. Published 2018 Feb 13. doi:10.3389/fnins.2018.00052 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5808288/
• Filippova YY, Kholodilina ME, Burmistrova AL. Cytokines and brain-derived neurotrophic factor in context of cognitive impairment in the elderly. Chelyabinsk State Univ. 2019;19(1S):18-19. doi:10.17816/MAJ19301. Available from: https://journals.eco-vector.com/MAJ/article/view/19301
• Winter B, Breitenstein C, Mooren FC, et al. High impact running improves learning. Neurobiol Learn Mem. 2007;87(4):597-609. doi:10.1016/j.nlm.2006.11.003 https://pubmed.ncbi.nlm.nih.gov/17185007/
• Donnelly JE, Hillman CH, Castelli D, et al. Physical Activity, Fitness, Cognitive Function, and Academic Achievement in Children: A Systematic Review. Med Sci Sports Exerc. 2016;48(6):1197-1222. doi:10.1249/MSS.0000000000000901 https://pubmed.ncbi.nlm.nih.gov/27182986/
• Burzynska AZ, Chaddock-Heyman L, Voss MW, et al. Physical activity and cardiorespiratory fitness are beneficial for white matter in low-fit older adults. PLoS One. 2014;9(9):e107413. Published 2014 Sep 15. doi:10.1371/journal.pone.0107413 https://pubmed.ncbi.nlm.nih.gov/25229455/
• Liu-Ambrose T, Nagamatsu LS, Graf P, Beattie BL, Ashe MC, Handy TC. Resistance training and executive functions: a 12-month randomized controlled trial. Arch Intern Med. 2010;170(2):170-178. doi:10.1001/archinternmed.2009.494 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3448565/
• Berman MG, Jonides J, Kaplan S. The Cognitive Benefits of Interacting With Nature. Psychol Sci. 2008;19(12):1207-1212. doi:10.1111/j.1467-9280.2008.02225.x https://pubmed.ncbi.nlm.nih.gov/19121124/
• Northey JM, Cherbuin N, Pumpa KL, Smee DJ, Rattray B. Exercise interventions for cognitive function in adults older than 50: a systematic review with meta-analysis. Br J Sports Med. 2018;52(3):154-160. doi:10.1136/bjsports-2016-096587 https://pubmed.ncbi.nlm.nih.gov/28438770/
• Herold F, Törpel A, Schega L, Müller NG. Functional and structural brain alterations following high-intensity aerobic exercise. Sci Rep. 2019;9(1):8595. Published 2019 Jun 13. doi:10.1038/s41598-019-45184-x https://pubmed.ncbi.nlm.nih.gov/31333805/
• Donnelly JE, Hillman CH, Greene JL, et al. Physical activity and academic achievement across the curriculum: Results from a 3-year cluster-randomized trial. Prev Med. 2017;99:140-145. doi:10.1016/j.ypmed.2017.02.006 https://pubmed.ncbi.nlm.nih.gov/28193490/

• 1
  Erickson KI, Hillman CH, Stillman CM, et al. Physical activity, cognition, and brain outcomes: a review of the 2018 physical activity guidelines. Med Sci Sports Exerc. 2019;51(12):2442-2451. doi:10.1249/MSS.0000000000002116 https://pubmed.ncbi.nlm.nih.gov/31095081/
• 2
  Stillman CM, Cohen J, Lehman ME, Erickson KI. Mediators of physical activity on neurocognitive function: A review at multiple levels of analysis. Front Hum Neurosci. 2016;10:626. Published 2016 Dec 6. doi:10.3389/fnhum.2016.00626 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5161022/
• 3
  Firth J, Stubbs B, Vancampfort D, et al. Effect of aerobic exercise on hippocampal volume in humans: A systematic review and meta-analysis. Neuroimage. 2020;116906. doi:10.1016/j.neuroimage.2020.116906 https://pubmed.ncbi.nlm.nih.gov/29113943/
• 4
  Erickson KI, Hillman CH, Stillman CM, et al. Physical activity, cognition, and brain outcomes: a review of the 2018 physical activity guidelines. Med Sci Sports Exerc. 2019;51(12):2442-2451. doi:10.1249/MSS.0000000000002116 https://pubmed.ncbi.nlm.nih.gov/31095081/
• 5
  Burzynska AZ, Chaddock-Heyman L, Voss MW, et al. Physical activity and cardiorespiratory fitness are beneficial for white matter in low-fit older adults. PLoS One. 2014;9(9):e107413. Published 2014 Sep 15. doi:10.1371/journal.pone.0107413 https://pubmed.ncbi.nlm.nih.gov/25229455/
• 6
  Szuhany KL, Bugatti M, Otto MW. A meta-analytic review of the effects of exercise on brain-derived neurotrophic factor. J Psychiatr Res. 2015;60:56-64. doi:10.1016/j.jpsychires.2014.10.003 https://pubmed.ncbi.nlm.nih.gov/25455510/
• 7
  Griffin ÉW, Mullally S, Foley C, Warmington SA, O’Mara SM, Kelly ÁM. Aerobic exercise improves hippocampal function and increases BDNF in the serum of young adult males. Physiol Behav. 2011;104(5):934-941. doi:10.1016/j.physbeh.2011.06.005 https://pubmed.ncbi.nlm.nih.gov/21722657/
• 8
  Berchtold NC, Castello N, Cotman CW. Exercise and time-dependent benefits to learning and memory. Neuroscience. 2010;167(3):588-597. doi:10.1016/j.neuroscience.2010.02.050 https://pubmed.ncbi.nlm.nih.gov/20219647/
• 9
  Liu PZ, Nusslock R. Exercise-mediated neurogenesis in the hippocampus via BDNF. Front Neurosci. 2018;12:52. Published 2018 Feb 13. doi:10.3389/fnins.2018.00052 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5808288/
• 10
  Sugawara J, Tomoto T, Repshas J, Zhang R, Tarumi T. Middle-aged endurance athletes exhibit lower cerebrovascular impedance than sedentary peers. J Appl Physiol (1985). 2020;129(2):335-342. doi:10.1152/japplphysiol.00239.2020. Published 2020 Jul 16. PMCID: PMC7473949. PMID: 32673159. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7473949/
• 11
  Dennis A, Thomas AG, Rawlings NB, et al. An ultra-high field magnetic resonance spectroscopy study of post exercise lactate, glutamate and glutamine change in the human brain. Front Physiol. 2015;6:351. doi:10.3389/fphys.2015.00351. Published 2015 Dec 17. https://www.frontiersin.org/articles/10.3389/fphys.2015.00351/full
• 12
  Burdette JH, Laurienti PJ, Espeland MA, et al. Using network science to evaluate exercise-associated brain changes in older adults. Front Aging Neurosci. 2010;2:23. Published 2010 Jun 25. doi:10.3389/fnagi.2010.00023 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2893375/
• 13
  Liu-Ambrose T, Nagamatsu LS, Graf P, Beattie BL, Ashe MC, Handy TC. Resistance training and executive functions: a 12-month randomized controlled trial. Arch Intern Med. 2010;170(2):170-178. doi:10.1001/archinternmed.2009.494 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3448565/
• 14
  Winter B, Breitenstein C, Mooren FC, et al. High impact running improves learning. Neurobiol Learn Mem. 2007;87(4):597-609. doi:10.1016/j.nlm.2006.11.003 https://pubmed.ncbi.nlm.nih.gov/17185007/
• 15
  Winter B, Breitenstein C, Mooren FC, et al. High impact running improves learning. Neurobiol Learn Mem. 2007;87(4):597-609. doi:10.1016/j.nlm.2006.11.003 https://pubmed.ncbi.nlm.nih.gov/17185007/
• 16
  Donnelly JE, Hillman CH, Castelli D, et al. Physical Activity, Fitness, Cognitive Function, and Academic Achievement in Children: A Systematic Review. Med Sci Sports Exerc. 2016;48(6):1197-1222. doi:10.1249/MSS.0000000000000901 https://pubmed.ncbi.nlm.nih.gov/27182986/
• 17
  Herold F, Törpel A, Schega L, Müller NG. Functional and structural brain alterations following high-intensity aerobic exercise. Sci Rep. 2019;9(1):8595. Published 2019 Jun 13. doi:10.1038/s41598-019-45184-x https://pubmed.ncbi.nlm.nih.gov/31333805/
• 18
  Northey JM, Cherbuin N, Pumpa KL, Smee DJ, Rattray B. Exercise interventions for cognitive function in adults older than 50: a systematic review with meta-analysis. Br J Sports Med. 2018;52(3):154-160. doi:10.1136/bjsports-2016-096587 https://pubmed.ncbi.nlm.nih.gov/28438770/
• 19
  Berman MG, Jonides J, Kaplan S. The Cognitive Benefits of Interacting With Nature. Psychol Sci. 2008;19(12):1207-1212. doi:10.1111/j.1467-9280.2008.02225.x https://pubmed.ncbi.nlm.nih.gov/19121124/