Why most of the fitness industry tries to sell you on abs is beyond me.
Six-pack abs—or the female equivalent, a “flat belly”—are a terrible motivator, because most people don’t consider it a realistic benefit of exercise. It’s an obvious, visible benchmark of extreme fitness, but it doesn’t actually do anything for you except look nice. And for most people (and virtually all business travelers) it seems like way too much work for something ephemeral and not super beneficial to your day-to-day life.
The medical community tries a different tack, the nebulous concept of longevity. A longer life is great, but it’s a terrible way to motivate you into building an active lifestyle today, because you don’t give a shit about future you— your brain thinks about “future you” in the same way that it thinks about a stranger, and simply has a hard time making very many sacrifices or changes for their benefit.
Instead, be active for current you. For a better daily life.
Of course, you probably don’t need to be sold on the general idea that being a more active person is, broadly speaking, better than being a less active person, but I’m still about to give you a long list of specific reasons that it’s better, for three reasons: because it’s even more valuable than you think, because the scientific community keeps coming out with research showing additional benefits on what seems like a weekly basis, and because I’m tired of doing this rant from memory without being able to point people at the research.
There is an immediate, concrete, non-pie-in-the-sky reason to improve your physical activity for just about everyone, whether improvement means going from nothing to something or going from something to something more.
A extremely modest amount of time invested into regularly moving your body is proven to help you become smarter, happier, a better performer at work, a better performer in the bedroom (both sleep and sex), get sick less often, and directly improve your life right now in dozens of other small and large ways.
Once you add the myriad indirect and psychological benefits that regular exercise can provide, like better self-image, self-discipline, and scientifically-validated improvements in how other people treat you? You’d be silly not to start some sort of activity practice.
More generally, physical activity is one of the best possible uses of your time, because it’s one of the few activities that gives you more time. Specifically, more useful time; more time in the day in the form of increased mental and physical energy and more time in your life in the form of increased useful life span.
Forget about the six pack. A six pack might be nice, but there are better reasons
31 of them, to be precise. There are probably more, but this post compiles every one I’ve ever encountered with scientific references to prove it, in one ~12,000 word behemoth of a post. Enjoy.
To that same point, in the interest of keeping this thing a reasonable length, this is an overview, not a detailed research review. Some of the studies I’m citing here are better than others, but I get into it where I think it’s relevant or it looks like the jury may truly still be out on something. I’ll do deeper dives into many of the benefits that have contentious or less-rigorous science behind them in future posts.
Also also: not all forms of activity confer all of these benefits to every person. I try to be clear when the research seems to favor one modality over others, but if you’re particularly interested in one of these benefits, have a look at the provided sources to see the specific durations or movements the researchers used.
On with the show.
The physical benefits of activity
Also, as a warning, these summaries get a little jargony and science-wordsy at points, because specific words mean specific things in scientific writing, and I’m trying to stay as accurate to the research I’m referencing as possible.
You don’t need to become a sweaty, grunting gym rat or a musclebound lunk to get a lot out of moving your body. The MUST GO HARD ALL THE TIME mentality espoused by most of the fitness industry just doesn’t bear out in the research — many of these benefits can be achieved with modest amounts of simple activity (and some seem to be most effective only when you’re not going all-out); more might be better, but just going for a brisk walk or doing a few dozen push-ups in the comfort of your own home can get you a majority of any of the following benefits.
It reduces your near- and long-term risk of dying.1Warburton, D. E.R. “Health Benefits of Physical Activity: the Evidence.” Canadian Medical Association Journal, vol. 174, no. 6, 2006, pp. 801–809., doi:10.1503/cmaj.051351. 2O’Donovan, Gary, et al. “Association of ‘Weekend Warrior’ and Other Leisure Time Physical Activity Patterns With Risks for All-Cause, Cardiovascular Disease, and Cancer Mortality.” JAMA Internal Medicine, vol. 177, no. 3, Jan. 2017, p. 335., 3Blair, Steven N. “Physical Fitness and All-Cause Mortality.” Jama, vol. 262, no. 17, Mar. 1989, p. 2395., 4 Oja, Pekka, et al. “Associations of Specific Types of Sports and Exercise with All-Cause and Cardiovascular-Disease Mortality: a Cohort Study of 80â 306 British Adults.” British Journal of Sports Medicine, vol. 51, no. 10, 2016, pp. 812–817., doi:10.1136/bjsports-2016-096822″.
Seriously modest amounts of exercise—weekend warrior, Saturday at the tennis court modest— are associated with a 40%+ reduced risk of getting a disease and/or dying from it when compared to a totally sedentary person.
The specific idea being researched here is “all-cause mortality” and it means death from all disease-related causes; everything from heart disease and atherosclerosis to dementia and other neurodegenerative diseases, cancer, and virtually everything else that we consider a “disease” in the traditional sense.
It improves sleep quality.5 Youngstedt, Shawn D., et al. “The Effects of Acute Exercise on Sleep: A Quantitative Synthesis.” Sleep, vol. 20, no. 3, 1997, pp. 203–214., doi:10.1093/sleep/20.3.203″. 6Yang, Pei-Yu, et al. “Exercise Training Improves Sleep Quality in Middle-Aged and Older Adults with Sleep Problems: a Systematic Review.” Journal of Physiotherapy, vol. 58, no. 3, 2012, pp. 157–163., doi:10.1016/s1836-9553(12)70106-6″. 7Reid, Kathryn J., et al. “Aerobic Exercise Improves Self-Reported Sleep and Quality of Life in Older Adults with Insomnia.” Sleep Medicine, vol. 11, no. 9, 2010, pp. 934–940., doi:10.1016/j.sleep.2010.04.014″.
Exercise has been shown to moderately improve sleep, in basically every way you can measure it — subjective quality measurements, time to fall asleep, increased slow-wave (physically restorative) sleep, total sleep time, reduced daytime sleepiness, reduced use of sleep medication, and so-on.
It’s especially effective as an intervention for older and insomnia-prone people, but improvements have also been shown in people who were already pretty good sleepers. It also doesn’t seem to matter if you’re doing primarily weight training or aerobic training in this case; both can be beneficial.
It improves physical endurance.8Tabata, Izumi, et al. “Effects of Moderate-Intensity Endurance and High-Intensity Intermittent Training on Anaerobic Capacity and VO2max.” Medicine and Science in Sports and Exercise, vol. 28, no. 10, 1996, pp. 1327–1330., doi:10.1097/00005768-199610000-00018″. 9Storer, Thomas W., et al. “Endurance Exercise Training during Haemodialysis Improves Strength, Power, Fatigability and Physical Performance in Maintenance Haemodialysis Patients.” Nephrology Dialysis Transplantation, vol. 20, no. 7, 2005, pp. 1429–1437., doi:10.1093/ndt/gfh784″. 10Storer, Thomas W., et al. “Endurance Exercise Training during Haemodialysis Improves Strength, Power, Fatigability and Physical Performance in Maintenance Haemodialysis Patients.” Nephrology Dialysis Transplantation, vol. 20, no. 7, 2005, pp. 1429–1437., doi:10.1093/ndt/gfh784″. 11Dalgas, U., et al. “Review: Multiple Sclerosis and Physical Exercise: Recommendations for the Application of Resistance-, Endurance- and Combined Training.” Multiple Sclerosis Journal, vol. 14, no. 1, 2008, pp. 35–53., doi:10.1177/1352458507079445″. 12Ramsey-Goldman, Rosalind, et al. “A Pilot Study on the Effects of Exercise in Patients with Systemic Lupus Erythematosus.” Arthritis & Rheumatism, vol. 13, no. 5, 2000, pp. 262–269., doi:10.1002/1529-0131(200010)13:5%3C262::aid-anr4%3E3.0.co;2-8.
This is sort of a “well duh” one, but I mention it to remind you that the benefits of physical endurance go well beyond just being able to exercise better in the future.
Physical endurance will let you better survive those (hopefully occasional) all-day offsites or crunch weeks at work, play more vigorously with your kids, walk around a new city all day without a break, take the stairs more often, and generally get more out of life without your body getting in the way. This goes double for a person who has other indications that could make them fatigue easily, like elderly people, people who have to do hemodialysis, and folks with lupus, multiple sclerosis or other autoimmune and neuromuscular disorders.
It strengthens the immune system.13Shinkai, S., et al. “Acute Exercise and Immune Function.” International Journal of Sports Medicine, vol. 13, no. 06, 1992, pp. 452–461., doi:10.1055/s-2007-1021297″. 14 Nieman, D. C., et al. “Upper Respiratory Tract Infection Is Reduced in Physically Fit and Active Adults.” British Journal of Sports Medicine, vol. 45, no. 12, Jan. 2010, pp. 987–992., doi:10.1136/bjsm.2010.077875″. 15 Nieman, David C., and Bente K. Pedersen. “Exercise and Immune Function.” Sports Medicine, vol. 27, no. 2, 1999, pp. 73–80., doi:10.2165/00007256-199927020-00001″.
Strangely enough, exercise actually depresses immune function in the short term, but rebounds within about two hours and improves in the long term (as measured by general susceptibility to illness).
This isn’t too surprising if you understand the concept of eustress. It’s the opposite of distress, and more commonly known as adaptive stress. It’s basically the scientific version of “what doesn’t kill you makes you stronger.” By putting small demands on a system like the body, you “teach” that system that being able to respond to that stress is necessary and valuable, and it devotes resources to make it stronger over time. It’s the mechanism that makes your muscles grow.
It improves bone density and mineral content.16 Kanis, J. A., et al. “Guidelines for Diagnosis and Management of Osteoporosis.” Osteoporosis International, vol. 7, no. 4, 1997, pp. 390–406., doi:10.1007/bf01623782″. 17Wright, Nicole C, et al. “The Recent Prevalence of Osteoporosis and Low Bone Mass in the United States Based on Bone Mineral Density at the Femoral Neck or Lumbar Spine.” Journal of Bone and Mineral Research, vol. 29, no. 11, 2014, pp. 2520–2526., doi:10.1002/jbmr.2269″. 18Bassey, E. J., and S. J. Ramsdale. “Increase in Femoral Bone Density in Young Women Following High-Impact Exercise.” Osteoporosis International, vol. 4, no. 2, 1994, pp. 72–75., doi:10.1007/bf01623226″. 19Layne, Jennifer E., and Miriam E. Nelson. “The Effects of Progressive Resistance Training on Bone Density: a Review.” Medicine & Science in Sports & Exercise, vol. 31, no. 1, 1999, pp. 25–30., doi:10.1097/00005768-199901000-00006″. 20Tucker, Larry A., et al. “Effect of Two Jumping Programs on Hip Bone Mineral Density in Premenopausal Women: A Randomized Controlled Trial.” American Journal of Health Promotion, vol. 29, no. 3, 2015, pp. 158–164., doi:10.4278/ajhp.130430-quan-200″.
Strong bones mean fewer bone fractures and a more durable body. This becomes critically important as you get older — almost 50% of US adults over 50 have Low Bone Mineral Density, and one in ten have full-blown osteoporosis.
This isn’t just a warning for the future, though. Young people are just as capable of slipping and falling or stepping off a curb in a strange way, and even a slight increase in bone density can reduce fracture risk and keep you from needing a cast or crutches.
Interventions as simple as jumping as high as you can 20 times a day have been proven to be effective in increasing hip bone density and mineral content, as have virtually all forms of resistance training and high-impact exercise.
It reduces your risk of some cancers.21Thune, Inger, and Anne-Sofie Furberg. “Physical Activity and Cancer Risk: Dose-Response and Cancer, All Sites and Site-Specific.” Medicine and Science in Sports and Exercise, vol. 33, no. Supplement, 2001, doi:10.1097/00005768-200106001-00025″. 22Li, Yingjun, et al. “Association between Physical Activity and All Cancer Mortality: Dose-Response Meta-Analysis of Cohort Studies.” International Journal of Cancer, vol. 138, no. 4, 2015, pp. 818–832., doi:10.1002/ijc.29828″. 23Ashcraft, Kathleen A., et al. “Efficacy and Mechanisms of Aerobic Exercise on Cancer Initiation, Progression, and Metastasis: A Critical Systematic Review of In Vivo Preclinical Data.” Cancer Research, vol. 76, no. 14, May 2016, pp. 4032–4050., doi:10.1158/0008-5472.can-16-0887″. 24Bernstein, L., et al. “Physical Exercise and Reduced Risk of Breast Cancer in Young Women.” JNCI Journal of the National Cancer Institute, vol. 86, no. 18, 1994, pp. 1403–1408., doi:10.1093/jnci/86.18.1403″.
There’s lots of evidence for this one. Exercise reduces cancer risk of all types at all ages in a dose-response manner (more exercise = less cancer risk), and continued exercise during treatment may also indicate better outcomes for folks who already have cancer.
Virtually none of the studies on this topic don’t identify the causal factor that creates reduced cancer risk, just an association between exercising and a reduced incidence of cancer, with more exercise being directly associated with lower risk. Which is to say, it’s probably a combination of a number of biochemical, physical and hormonal effects of physical activity, and maybe even just a byproduct of a generally healthy lifestyle (ie: people who exercise more are just healthier in other ways too, although many of the referenced studies try to control for this) — the mechanism isn’t clear, but the relationship is. People who exercise more get less cancer.
It improves muscle strength, size, and tone.25Winett, Richard A., and Ralph N. Carpinelli. “Potential Health-Related Benefits of Resistance Training.” Preventive Medicine, vol. 33, no. 5, 2001, pp. 503–513., doi:10.1006/pmed.2001.0909″. 26Kraemer, William J., et al. “Resistance Training for Health and Performance.” Current Sports Medicine Reports, vol. 1, no. 3, 2002, pp. 165–171., doi:10.1249/00149619-200206000-00007″. 27Kosek, D. J. “Efficacy of 3 Days/Wk Resistance Training on Myofiber Hypertrophy and Myogenic Mechanisms in Young vs. Older Adults.” Journal of Applied Physiology, vol. 101, no. 2, June 2006, pp. 531–544., doi:10.1152/japplphysiol.01474.2005″. 28Johnston, Adam P.w., et al. “Resistance Training, Sarcopenia, and the Mitochondrial Theory of Aging.” Applied Physiology, Nutrition, and Metabolism, vol. 33, no. 1, 2008, pp. 191–199., doi:10.1139/h07-141″. 29Johnston, Adam P.w., et al. “Resistance Training, Sarcopenia, and the Mitochondrial Theory of Aging.” Applied Physiology, Nutrition, and Metabolism, vol. 33, no. 1, 2008, pp. 191–199., doi:10.1139/h07-141″. 30Fiatarone, Maria A. “High-Intensity Strength Training in Nonagenarians.” Jama, vol. 263, no. 22, 1990, p. 3029., doi:10.1001/jama.1990.03440220053029″.
Another “well duh,” and another reminder that while exercise has a direct impact on physical aesthetics — and there’s no shame or judgement in wanting to look good without your clothes on, whether or not that means a shredded six-pack — it also improves general quality of life and resilience for anyone of any age, from 15 to 95 (although it’s easier if you start younger). No one wants to throw out their back when trying to pick up an air conditioner, or be unable to push their car out of the snow, or have to sit out on a scenic hike because their legs can’t handle it, or be unable to be independently mobile as they get older.
Most of the research here is specifically referring to resistance (strength) training, and in pretty modest amounts; the point of diminishing returns for the general health benefits of muscle strength and size is 15 to 20 minutes twice a week.
Resistance training becomes doubly beneficial for older individuals, who are susceptible to sarcopenia, a gradual wasting of muscle tissue as we age — if you don’t use it, you do, in fact, lose it. Even small amounts of exercise stave off this disease, which translates directly to more years of independent mobility and function, and fewer in an assisted-living home.
It improves digestion.31chryver, Anneke M. De, et al. “Effects of Regular Physical Activity on Defecation Pattern in Middle-Aged Patients Complaining of Chronic Constipation.” Scandinavian Journal of Gastroenterology, vol. 40, no. 4, 2005, pp. 422–429., doi:10.1080/00365520510011641″. 32Moses, Frank M. “The Effect of Exercise on the Gastrointestinal Tract1.” Sports Medicine, vol. 9, no. 3, 1990, pp. 159–172., doi:10.2165/00007256-199009030-00004″.
More specifically, it can boost the quantity and diversity of healthy gut bacteria, promote colonic regularity and reduce constipation, and reduce the risk of diverticular disease over time.
In the short term, the physical act of exercise actually slows digestion, but the long term the benefits outweigh the short-term problems — to a point. Extreme training loads can actually cause gastrointestinal bleeding and other symptoms in long distance endurance athletes with high training volumes.
Digression: up to this point, we’ve been talking about the benefits of exercise as following the law diminishing returns, where more is always better, just not the same amount of better after a certain point. That’s not actually the whole story. There is a point far past the point of diminishing returns where too much physical activity can hurt your body, generally referred to as “overtraining.”
While it’s important to bring up, very few people need to worry much about overtraining. The point where it occurs is so far past what anyone who isn’t a professional athlete or a lunatic exercise fanatic would reasonably do (think dozens of hours of intense training for many consecutive weeks) that it’s not worth worrying about.
One exception: Overtraining Syndrome is caused by dramatically increasing relative workload, so someone going from “haven’t worked out in a year” to “Crossfit six days a week” could potentially cause a problem for themselves, although it’s still not likely. You’d probably be too sore to work out enough to harm yourself or develop an overuse injury in a specific muscle, or give yourself Rhabdomyolysis (which is no joke) before you managed to give yourself Overtraining Syndrome.
It reduces asthma symptoms.33Veldhoven, N Hmj Van, et al. “Children with Asthma and Physical Exercise: Effects of an Exercise Programme.” Clinical Rehabilitation, vol. 15, no. 4, 2001, pp. 360–370., doi:10.1191/026921501678310162″. 34Carson, Kristin V., et al. “Physical Training for Asthma.” Cochrane Database of Systematic Reviews, Wiley-Blackwell, Sept. 2013. Crossref, doi:10.1002/14651858.cd001116.pub4.
You might think that people with asthma should avoid cardio or other types of exercise that makes them breathe heavily, but regularly training your respiratory system—in ways that don’t trigger an attack—can actually strengthen the lungs and airways and reduce symptoms, especially in kids.
The key here seems to be making sure the asthma is otherwise well-managed and starting with activity that’s low enough intensity that it won’t cause cause an attack — as ability gets better over time, intensity can be increased.
It improves sex drive and sexual function.35Lewis, Ronald W., et al. “Epidemiology/Risk Factors of Sexual Dysfunction.” The Journal of Sexual Medicine, vol. 1, no. 1, 2004, pp. 35–39., doi:10.1111/j.1743-6109.2004.10106.x”. 36Bacon, Constance G., et al. “Sexual Function in Men Older Than 50 Years of Age: Results from the Health Professionals Follow-up Study.” Annals of Internal Medicine, vol. 139, no. 3, May 2003, p. 161., doi:10.7326/0003-4819-139-3-200308050-00005″. 37Lorenz, Tierney Ahrold, and Cindy May Meston. “Exercise Improves Sexual Function In Women Taking Antidepressants: Results From A Randomized Crossover Trial.” Depression and Anxiety, vol. 31, no. 3, Jan. 2013, pp. 188–195., doi:10.1002/da.22208″. 38White, James R., et al. “Enhanced Sexual Behavior in Exercising Men.” Archives of Sexual Behavior, vol. 19, no. 3, 1990, pp. 193–209., doi:10.1007/bf01541546″. 39Hamilton, Lisa Dawn, et al. “The Roles of Testosterone and Alpha-Amylase in Exercise-Induced Sexual Arousal in Women.” The Journal of Sexual Medicine, vol. 5, no. 4, 2008, pp. 845–853., doi:10.1111/j.1743-6109.2007.00751.x”.
A little bit of time in the gym can pay off big time in the sack — physical activity is directly linked to an increased sex drive, as well as improved sexual performance, as measured by frequency of intimate activities, physiological arousal (blood flow, etc), reliability of adequate function during sex, percentage of self-reported satisfying encounters, and a few other metrics.
It also reduces the risk of developing sexual disfunction as you age, and boosts levels of a number of feel-good neurochemicals like serotonin, endorphins, and testosterone, all of which are also related to greater sex drive and improved sexual function.
A lot of the research here is attempting to use exercise as an intervention for folks that might otherwise experience diminished sex drive, like postmenopausal women and people taking antidepressants, but there are at least a couple of studies that show the same results in healthy people, with bouts as short as 20 minutes on a treadmill at moderate intensity displaying an immediate positive effect in women.
It reduces menstrual pain.40Rostami, Maryam, et al. “The Effect of Exercise on Primary Dysmenorrhea.” Gender Medicine, vol. 3, 2006, doi:10.1016/s1550-8579(06)80151-8″. 41Metheny, William P., and Roger P. Smith. “The Relationship among Exercise, Stress, and Primary Dysmenorrhea.” Journal of Behavioral Medicine, vol. 12, no. 6, 1989, pp. 569–586., doi:10.1007/bf00844826″. 42Motahari-Tabari, Narges, et al. “Comparison of the Effect of Stretching Exercises and Mefenamic Acid on the Reduction of Pain and Menstruation Characteristics in Primary Dysmenorrhea: A Randomized Clinical Trial.” Oman Medical Journal, vol. 32, no. 1, Mar. 2017, pp. 47–53., doi:10.5001/omj.2017.09″.
This is one of the rare ones where it’s not just regular activity that helps, but acute (one-time, right now) activity as well — exercise can increase pelvic blood flow and reduce cortisol, as well as generally improve mood, all of which have been proposed as the reason mild activity can have immediate pain-reducing effects.
Most of the research that shows good outcomes either isn’t specific about what kind of exercise or biases things that directly stretch or exercise the legs and hips, like squats, leg lifts, running, and yoga, but there’s not enough research here to determine what kind of exercise is most effective, or if it’s effective for everyone—some studies show no benefit at all, and many of the ones that do aren’t particularly well-designed.
Bottom line: this one might require some self-experimentation to see if it works for you. It won’t cause any harm.
It improves skin quality.43Crane, Justin D., et al. “Exercise-Stimulated Interleukin-15 Is Controlled by AMPK and Regulates Skin Metabolism and Aging.” Aging Cell, vol. 14, no. 4, 2015, pp. 625–634., doi:10.1111/acel.12341″. 44Safdar, A., et al. “Endurance Exercise Rescues Progeroid Aging and Induces Systemic Mitochondrial Rejuvenation in MtDNA Mutator Mice.” Proceedings of the National Academy of Sciences, vol. 108, no. 10, 2011, pp. 4135–4140., doi:10.1073/pnas.1019581108″.
Everyone’s skin degenerates slightly as we age. It gets less stretchy, uneven, more susceptible to inflammation, and so-on.
Folks who regularly exercise have less this deterioration, and an aerobic exercise program of as short as 3 months been shown to be enough to begin to provide similar benefits in previously-sedentary individuals. Unfortunately, these benefits don’t seem to extend to boosting reticular dermis collagen (one of the primary culprits of wrinkles), but cover virtually all of the other common aging markers, including relative thicknesses of certain layers of skin and mitochondrial health.
This benefit isn’t as well-researched as some of the other benefits, with many of the studies occurring on mice, not people. There’s only one really sturdy human trial, and it happened in 2015.
This isn’t too surprising, considering this line of research is new, and mouse and monkey studies are common in early-stage research, because testing on them is cheaper and easier to get approvals for—not to mention if you kill any you won’t be tried for manslaughter.
Animal studies are still worth looking at; mice and monkeys are generally a good predictor of how humans will react to something — mice share 92 percent of our genes, and chimpanzees a whopping 98 percent — but they still aren’t a perfect facsimile for humans, so they need to be looked at with some caution.
It reduces and even reverses the physical and biochemical effects of stress.45Rimmele, Ulrike, et al. “Trained Men Show Lower Cortisol, Heart Rate and Psychological Responses to Psychosocial Stress Compared with Untrained Men.” Psychoneuroendocrinology, vol. 32, no. 6, Elsevier BV, July 2007, pp. 627–635., doi:10.1016/j.psyneuen.2007.04.005″. 46Kamei, Tsutomu, et al. “Decrease in Serum Cortisol during Yoga Exercise Is Correlated with Alpha Wave Activation.” Perceptual and Motor Skills, vol. 90, no. 3, SAGE Publications, June 2000, pp. 1027–1032., doi:10.2466/pms.2000.90.3.1027″. 47Nabkasorn, Chanudda, et al. “Effects of Physical Exercise on Depression, Neuroendocrine Stress Hormones and Physiological Fitness in Adolescent Females with Depressive Symptoms.” European Journal of Public Health, vol. 16, no. 2, Oxford University Press (OUP), Aug. 2005, pp. 179–184., doi:10.1093/eurpub/cki159″. 48Rudolph, David L., and Edward McAuley. “Cortisol and Affective Responses to Exercise.” Journal of Sports Sciences, vol. 16, no. 2, Informa UK Limited, Jan. 1998, pp. 121–128., doi:10.1080/026404198366830″. 49Hill, E. E., et al. “Exercise and Circulating Cortisol Levels: The Intensity Threshold Effect.” Journal of Endocrinological Investigation, vol. 31, no. 7, Springer Nature, July 2008, pp. 587–591., doi:10.1007/bf03345606″.
Stress is really, really bad for you. Whether it’s caused by your environment, your job, or your home life, it’s associated with everything from weight gain and poor nutrient partitioning (more of your food being stored as fat rather than being used for energy or muscle repair) to depression to memory impairment to heart disease, premature aging, and even death.
There are a lot of ways to manage and reduce stress, and you should employ more of them than just exercise if you have a high-stress job or home life, but physical activity remains one of the best.
Not only can a single session of exercise cause your levels of the primary stress hormone cortisol to drop, people who regularly exercise have less intense cortisol responses to both physically and mentally stressful situations.
It improves glucose tolerance, insulin sensitivity, metabolic rate, and body composition.50Dunstan, D. W., et al. “High-Intensity Resistance Training Improves Glycemic Control in Older Patients With Type 2 Diabetes.” Diabetes Care, vol. 25, no. 10, American Diabetes Association, Oct. 2002, pp. 1729–1736. Crossref, doi:10.2337/diacare.25.10.1729″. 51Sigal, Ronald J., et al. “Effects of Aerobic Training, Resistance Training, or Both on Glycemic Control in Type 2 Diabetes.” Annals of Internal Medicine, vol. 147, no. 6, American College of Physicians, Sept. 2007, p. 357. Crossref, doi:10.7326/0003-4819-147-6-200709180-00005″. 52Kraemer, William J., et al. “Resistance Training for Health and Performance.” Current Sports Medicine Reports, vol. 1, no. 3, 2002, pp. 165–171., doi:10.1249/00149619-200206000-00007″. 53Di Loreto, C., et al. “Effects of Whole-Body Vibration Exercise on the Endocrine System of Healthy Men.” Journal of Endocrinological Investigation, vol. 27, no. 4, Springer Nature, Apr. 2004, pp. 323–327. Crossref, doi:10.1007/bf03351056″.
The most efficient way to make an impact on any of these four things continues to be eating better, but physical activity can also make a measurable, positive impact on one or all of them, either directly or indirectly.
To elaborate: while they are all in fact measurably improved by physical activity, I would still not recommend making physical activity your primary strategy to change any of these biomarkers — I prefer to see exercise as a separate angle of attack, a bonus approach that when combined with good nutrition will take you a lot farther a lot faster. Not to mention, the tit-for-tat mentality of “burning off” dietary indiscretions is both prone to inaccuracies in calculation and can lead to unpleasant, obsessive ‘self-punishment’ behaviors.
It can help you withstand and counteract the physical toll of an otherwise deskbound life.54Pawlowsky, Sarah B., et al. “Stability of Kyphosis, Strength, and Physical Performance Gains 1 Year After a Group Exercise Program in Community-Dwelling Hyperkyphotic Older Women.” Archives of Physical Medicine and Rehabilitation, vol. 90, no. 2, Elsevier BV, Feb. 2009, pp. 358–361., doi:10.1016/j.apmr.2008.07.016″. 55Yazici, Ahmet Gökhan, and Mohsen Mohammadi. “The Effect of Corrective Exercises on the Thoracic Kyphosis and Lumbar Lordosis of Boy Students.” Turkish Journal of Sport and Exercise, Turkish Journal of Sport and Exercise, Aug. 2017, pp. 177–181., doi:10.15314/tsed.293311″. 56Daniel W. Vaughn, and Eugene W. Brown. “The Influence of an in-Home Based Therapeutic Exercise Program on Thoracic Kyphosis Angles.” Journal of Back and Musculoskeletal Rehabilitation, vol. 20, no. 4, IOS Press, Dec. 2007, pp. 155–165, doi:10.3233/BMR-2007-20404″. 57Malmivaara, Antti, et al. “The Treatment of Acute Low Back Pain — Bed Rest, Exercises, or Ordinary Activity?” New England Journal of Medicine, vol. 332, no. 6, New England Journal of Medicine (NEJM/MMS), Feb. 1995, pp. 351–355., doi:10.1056/nejm199502093320602″. 58Bullock-Saxton, Joanne E., et al. “Reflex Activation of Gluteal Muscles in Walking.” Spine, vol. 18, no. 6, 1993, pp. 704–708., doi:10.1097/00007632-199305000-00005″.
Even when you do it right, sitting at a desk for hours on end is not particularly good for your spine, lower back, abs, shoulders, hips, quads, hamstrings, or glutes. It can also cause lower and upper back pain, shoulder rounding, tight and short hip flexors, and poor glute function, which can then cause a whole host of other problems when you try and do other relatively simple tasks, like go for a jog or pick something heavy up from the ground.
Making these muscles stronger and more flexible helps your body fight and even reverse this damage, and has been specifically proven to reduce or relieve lower back pain, one of the most common desk-jockey problems. This low-back benefit comes specifically moving, strengthening and stretching the specific muscles involved, not just general activity, so make sure you’re getting your deadlifts and deep lunges in.
The mental benefits of activity
Even if you’re bullish on the singularity happening in the next ten or fifteen years or otherwise don’t care to prioritize a high-performing, pain free body, it doesn’t stop there—physical activity also confers a variety of impressive mental and cognitive benefits as well.
It reduces anxiety.59Broocks, Andreas, et al. “Comparison of Aerobic Exercise, Clomipramine, and Placebo in the Treatment of Panic Disorder.” American Journal of Psychiatry, vol. 155, no. 5, American Psychiatric Publishing, May 1998, pp. 603–609., doi:10.1176/ajp.155.5.603″. 60Broocks, Andreas, et al. “Exercise Avoidance and Impaired Endurance Capacity in Patients with Panic Disorder.” Neuropsychobiology, vol. 36, no. 4, S. Karger AG, 1997, pp. 182–187., doi:10.1159/000119381″. 61Ströhle, Andreas, et al. “The Acute Antipanic Activity of Aerobic Exercise.” American Journal of Psychiatry, vol. 162, no. 12, American Psychiatric Publishing, Dec. 2005, pp. 2376–2378., doi:10.1176/appi.ajp.162.12.2376″. 62Ströhle, Andreas, et al. “The Acute Antipanic and Anxiolytic Activity of Aerobic Exercise in Patients with Panic Disorder and Healthy Control Subjects.” Journal of Psychiatric Research, vol. 43, no. 12, Elsevier BV, Aug. 2009, pp. 1013–1017., doi:10.1016/j.jpsychires.2009.02.004″. 63Strickland, Justin C., and Mark A. Smith. “The Anxiolytic Effects of Resistance Exercise.” Frontiers in Psychology, vol. 5, Frontiers Media SA, July 2014., doi:10.3389/fpsyg.2014.00753″.
Regular exercise significantly reduces the occurrence and severity of both panic attacks and general anxiety. This is true both in people who have chronic panic/anxiety disorders and in otherwise-healthy folks; seemingly no matter who you are or how you do it, exercise can make you feel less anxious.
Even better, just one 30 minute treadmill run or moderate-intensity lifting session has been shown to have immediate anxiolytic (anti-anxiety) benefits. It seems that moderate intensity is key here—too little intensity (think a brisk walk) isn’t enough to see much benefit, but too much intensity and you lose the benefit too, presumably because super-high intensity work is too mentally/physically taxing. So, if you expect to have an anxiety-producing day, get a jog or a quick lift in, but maybe skip the sprints or the one-rep-max test.
It helps your body preserve existing brain cells and produce new ones.64Voss, M. W., et al. “Exercise, Brain, and Cognition across the Life Span.” Journal of Applied Physiology, vol. 111, no. 5, American Physiological Society, Apr. 2011, pp. 1505–1513., doi:10.1152/japplphysiol.00210.2011″. 65Cotman, C. “Exercise: A Behavioral Intervention to Enhance Brain Health and Plasticity.” Trends in Neurosciences, vol. 25, no. 6, Elsevier BV, June 2002, pp. 295–301., doi:10.1016/s0166-2236(02)02143-4″. 66Hillman, Charles H., et al. “Be Smart, Exercise Your Heart: Exercise Effects on Brain and Cognition.” Nature Reviews Neuroscience, vol. 9, no. 1, Springer Nature, Jan. 2008, pp. 58–65., doi:10.1038/nrn2298″.
This benefit is mostly talked about and studied in the context of cognitive decline, where the goal is to prevent brain cells from becoming senescent and dying off as we age, but the exact same mechanisms can also make you sharper, more alert, better at learning, better at remembering what you learn, and generally better at mental tasks right now, after as little as a single session of vigorous activity.
Those benefits aren’t just proven by things like cognition tests: MRIs have shown that physical activity actually grows and maintains your brain cells.
Both strength training and aerobic conditioning seem to have this effect, and doing both seems to have a stronger impact than doing just one.
I’ve yet to see a good article explaining exactly why this happens, but the research indicating that it does happen is very strong. There are definitely growth-signaling chemicals called neurotrophins or neurotrophic factors at work, as well as positive effects of improved blood flow and oxygen in the brain, but a bunch of other chemicals, systems, and signaling pathways may also be involved.
It improves subjective feelings of fatigue and low energy.67Puetz, Timothy W. “Physical Activity and Feelings of Energy and Fatigue.” Sports Medicine, vol. 36, no. 9, Springer Nature, 2006, pp. 767–780., doi:10.2165/00007256-200636090-00004″. 68O’Connor, Patrick J., and Timothy W. Puetz. “Chronic Physical Activity and Feelings of Energy and Fatigue.” Medicine & Science in Sports & Exercise, vol. 37, no. 2, Ovid Technologies (Wolters Kluwer Health), Feb. 2005, pp. 299–305., doi:10.1249/01.mss.0000152802.89770.cf”. 69Nicklas, Barbara J., et al. “Relationship of Objectively-Measured Habitual Physical Activity to Chronic Inflammation and Fatigue in Middle-Aged and Older Adults.” The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, vol. 71, no. 11, Oxford University Press (OUP), July 2016, pp. 1437–1443., doi:10.1093/gerona/glw131″. 70Roemmich, James N., et al. “Influence of an Interpersonal Laboratory Stressor on Youths’ Choice to Be Physically Active.” Obesity Research, vol. 11, no. 9, Wiley-Blackwell, Sept. 2003, pp. 1080–1087., doi:10.1038/oby.2003.148″.
People who perform more habitual physical activity also self-report lower feelings of fatigue and higher overall energy in a number of studies. But also, people who experience chronic fatigue and/or inflammation reported reduced physical activity while symptoms flare up, and increased physical activity when symptoms go away.
This probably means that this benefit operates as a feedback loop: more exercise means more energy which means even more exercise and so-on. But also, less energy means less exercise means less energy and so-on. Practically, it implies that dragging yourself to the gym when you’re tired is the most important time to go, because it can be the first step in breaking a cycle of fatigue and building a cycle of vitality.
It counteracts the mental effects of stress.71Salmon, Peter. “Effects of Physical Exercise on Anxiety, Depression, and Sensitivity to Stress.” Clinical Psychology Review, vol. 21, no. 1, Elsevier BV, Feb. 2001, pp. 33–61., doi:10.1016/s0272-7358(99)00032-x”. 72Southwick, Steven M., et al. “The Psychobiology of Depression and Resilience to Stress: Implications for Prevention and Treatment.” Annual Review of Clinical Psychology, vol. 1, no. 1, Annual Reviews, Apr. 2005, pp. 255–291., doi:10.1146/annurev.clinpsy.1.102803.143948″. 73Asmundson, Gordon J. G., et al. “Let’s Get Physical: A Contemporary Review Of The Anxiolytic Effects Of Exercise For Anxiety And Its Disorders.” Depression and Anxiety, vol. 30, no. 4, Wiley-Blackwell, Jan. 2013, pp. 362–373., doi:10.1002/da.22043″. 74Van Rhenen, Willem, et al. “The Effect of a Cognitive and a Physical Stress-Reducing Programme on Psychological Complaints.” International Archives of Occupational and Environmental Health, vol. 78, no. 2, Springer Nature, Mar. 2005, pp. 139–148., doi:10.1007/s00420-004-0566-6″. 75Yeung, Robert R. “The Acute Effects of Exercise on Mood State.” Journal of Psychosomatic Research, vol. 40, no. 2, Elsevier BV, Feb. 1996, pp. 123–141., doi:10.1016/0022-3999(95)00554-4″.
The tricky thing about stress is your body doesn’t care if it’s “real” or “perceived;” physical or mental — your body and mind react to stress in the same bad way, and then feed off of each other to create all kinds of terrible negative health outcomes for you. The physical effects of stress cause the mental effects of stress cause the physical effects of stress cause the mental effects of stress, and so-on.
We’ve already covered how physical activity both reverses the impact of (and improves your resilience to) the physical and biochemical impact of stress. But, it also has proven psychological benefits in relation to stress and anxiety, and not just little ones — some studies show as much benefit as non-physical interventions like therapy and meditation.
This makes exercise a rare double-whammy for stress management and reduction: it’s able to break or reverse a stress spiral at both ends simultaneously (this goes for panic and anxiety too, which are fundamentally an out-of-control version of the feedback loop we’re talking about). Meditative or mindful exercise practices like Yoga, Tai Chi and Qigong have the most research confirming their direct effect on stress, but aerobic and strength exercise are definitely also effective, with moderate-intensity exercise seemingly better than max-intensity work.
It improves mood and reduces symptoms of depression.76Salmon, Peter. “Effects of Physical Exercise on Anxiety, Depression, and Sensitivity to Stress.” Clinical Psychology Review, vol. 21, no. 1, Elsevier BV, Feb. 2001, pp. 33–61., doi:10.1016/s0272-7358(99)00032-x”. 77Penedo, Frank J., and Jason R. Dahn. “Exercise and Well-Being: A Review of Mental and Physical Health Benefits Associated with Physical Activity.” Current Opinion in Psychiatry, vol. 18, no. 2, Ovid Technologies (Wolters Kluwer Health), Mar. 2005, pp. 189–193., doi:10.1097/00001504-200503000-00013″. 78Smith, Patrick J., and James A. Blumenthal. “Exercise and Physical Activity in the Prevention and Treatment of Depression.” Routledge Handbook of Physical Activity and Mental Health, doi:10.4324/9780203132678.ch8″. 79MacGillivray, Lindsey, et al. “The Comparative Effects of Environmental Enrichment with Exercise and Serotonin Transporter Blockade on Serotonergic Neurons in the Dorsal Raphe Nucleus.” Synapse, vol. 66, no. 5, Wiley-Blackwell, Jan. 2012, pp. 465–470., doi:10.1002/syn.21511″. 80Trivedi, Madhukar H., et al. “Exercise as an Augmentation Treatment for Nonremitted Major Depressive Disorder.” The Journal of Clinical Psychiatry, vol. 72, no. 5, Physicians Postgraduate Press, Inc, May 2011, pp. 677–684., doi:10.4088/jcp.10m06743″. 81Arent, Shawn M., et al. “The Effects of Exercise on Mood in Older Adults: A Meta-Analytic Review.” Journal of Aging and Physical Activity, vol. 8, no. 4, Human Kinetics, Oct. 2000, pp. 407–430., doi:10.1123/japa.8.4.407″. 82Blumenthal, James A., et al. “Exercise and Pharmacotherapy in the Treatment of Major Depressive Disorder.” Psychosomatic Medicine, vol. 69, no. 7, Ovid Technologies (Wolters Kluwer Health), Sept. 2007, pp. 587–596., doi:10.1097/psy.0b013e318148c19a”. 83Arent, Shawn M., et al. “The Effects of Exercise on Mood in Older Adults: A Meta-Analytic Review.” Journal of Aging and Physical Activity, vol. 8, no. 4, Human Kinetics, Oct. 2000, pp. 407–430., doi:10.1123/japa.8.4.407.
There is an overwhelming amount of research on this: exercise improves your mood. In recent years, it’s even been indicated as an adjunct therapy for depression — in addition to antidepressants, therapy, etc — and in some research has been shown as an effective replacement for people who don’t respond or only partially respond to traditional “antidepressants” like SSRIs.
Even if you’re not clinically depressed, exercise is a powerful mood enhancer for anyone who has the occasional bad day or unhappy moment, both acutely (ie: go for a walk or a jog when you’re feeling low) and chronically (ie: regular exercise reduces your general likelihood for bad days).
I probably don’t have to say this, but just in case: if you’re on antidepressants, please don’t stop taking them and work out more instead just because of this article. There’s not much risk in adding activity to your life and seeing if it improves how you feel, but always talk to your doctor before changing a medication regimen or dosage.
It boosts creativity.84Oppezzo, Marily, and Daniel L. Schwartz. “Give Your Ideas Some Legs: The Positive Effect of Walking on Creative Thinking.” Journal of Experimental Psychology: Learning, Memory, and Cognition, vol. 40, no. 4, American Psychological Association (APA), 2014, pp. 1142–1152., doi:10.1037/a0036577″. 85Steinberg, H., et al. “Exercise Enhances Creativity Independently of Mood.” British Journal of Sports Medicine, vol. 31, no. 3, BMJ, Sept. 1997, pp. 240–245., doi:10.1136/bjsm.31.3.240″. 86Blanchette, David M., et al. “Aerobic Exercise and Creative Potential: Immediate and Residual Effects.” Creativity Research Journal, vol. 17, no. 2–3, Informa UK Limited, July 2005, pp. 257–264., doi:10.1080/10400419.2005.9651483″. 87Gondola, Joan C., and Bruce W. Tuckman. “Effects of a Systematic Program of Exercise on Selected Measures of Creativity.” Perceptual and Motor Skills, vol. 60, no. 1, SAGE Publications, Feb. 1985, pp. 53–54., doi:10.2466/pms.1918.104.22.168″. 88S. Colzato, Lorenza, et al. “The Impact of Physical Exercise on Convergent and Divergent Thinking.” Frontiers in Human Neuroscience, vol. 7, Frontiers Media SA, 2013., doi:10.3389/fnhum.2013.00824″.
A walk around the block or even a light calisthenics workout when you’re feeling mentally stuck turns out to be a great way to un-stick yourself.
Most of the research here is around the idea that bouts of low-to-moderate intensity exercise improve creativity during the activity and up to a few hours afterwards, but there’s also a decent amount of evidence that regular exercisers do better on tests of creativity, with just a 16-week exercise program creating a small but significant improvement.
The specific tests researchers have used to determine ‘creativity’ have evolved over the years as our understanding of the concept has changed, but the relationship between exercise and creativity seems to survive every time a new test becomes the standard — a positive sign that this isn’t just a coincidental relationship.
It improves attention and focus.89Chang, Y. K., et al. “Effect of Acute Exercise on Executive Function in Children with Attention Deficit Hyperactivity Disorder.” Archives of Clinical Neuropsychology, vol. 27, no. 2, Oxford University Press (OUP), Feb. 2012, pp. 225–237., doi:10.1093/arclin/acr094″. 90Chang, Y. K., et al. “Effects of an Aquatic Exercise Program on Inhibitory Control in Children with ADHD: A Preliminary Study.” Archives of Clinical Neuropsychology, vol. 29, no. 3, Oxford University Press (OUP), Apr. 2014, pp. 217–223., doi:10.1093/arclin/acu003″. 91Ratey, John J., and Eric Hagerman. Spark: the Revolutionary New Science of Exercise and the Brain. Little, Brown, 2013, http://amzn.to/2jCfCJQ.
Yet another one where both single sessions of exercise and continued regimens seem to be beneficial.
By boosting levels of dopamine and norepinephrine in the short-term, and helping your brain create additional receptor sites for both of these chemicals in the long-term, working out helps you stay on task longer, make less impulsive responses to distractions, and improves signal-to-noise of the electrical impulses in your brain.
It’s even been shown to provide enough benefit to help people (well, kids. The studies mostly focus on kids.) with clinically diagnosable ADD and ADHD — not as effective as medication, but still a significant benefit.
It improves memory.92Hillman, Charles H., et al. “Be Smart, Exercise Your Heart: Exercise Effects on Brain and Cognition.” Nature Reviews Neuroscience, vol. 9, no. 1, Springer Nature, Jan. 2008, pp. 58–65., doi:10.1038/nrn2298″. 93Coles, Kathryn, and Philip D. Tomporowski. “Effects of Acute Exercise on Executive Processing, Short-Term and Long-Term Memory.” Journal of Sports Sciences, vol. 26, no. 3, Informa UK Limited, Feb. 2008, pp. 333–344., doi:10.1080/02640410701591417″. 94Labban, Jeffrey D., and Jennifer L. Etnier. “Effects of Acute Exercise on Long-Term Memory.” Research Quarterly for Exercise and Sport, vol. 82, no. 4, Informa UK Limited, Dec. 2011, pp. 712–721., doi:10.1080/02701367.2011.10599808″. 95Salas, Carlos R., et al. “Walking before Study Enhances Free Recall but Not Judgement-of-Learning Magnitude.” Journal of Cognitive Psychology, vol. 23, no. 4, Informa UK Limited, June 2011, pp. 507–513., doi:10.1080/20445911.2011.532207″. 96Alves, Christiano R. R., et al. “Influence of Acute High-Intensity Aerobic Interval Exercise Bout on Selective Attention and Short-Term Memory Tasks.” Perceptual and Motor Skills, vol. 118, no. 1, SAGE Publications, Feb. 2014, pp. 63–72., doi:10.2466/22.06.pms.118k10w4″.
This is true for both short-term and long-term recall, across a few different testing methodologies, with some showing a 25% or greater increase.
Like most of the other things associated with executive function (attention, focus, creativity, etc), research seems to show that exercise that is highly taxing on your central nervous system, like interval training and heavy weight lifting, provide less of a short term benefit or even a negative short term benefit as compared to low-to-moderate intensity aerobic exercise. More is not necessarily better, and even a brisk ten-minute walk can be enough.
It improves working memory.97Dunsky, Ayelet, et al. “The Effects of a Resistance vs. an Aerobic Single Session on Attention and Executive Functioning in Adults.” PLOS ONE, edited byConrad P. Earnest , vol. 12, no. 4, Public Library of Science (PLoS), Apr. 2017, p. e0176092., doi:10.1371/journal.pone.0176092″. 98Miyake, Akira. Models of Working Memory: Mechanisms of Active Maintenance and Excutive Control. Cambridge Univ. Press, 2007, http://amzn.to/2jC8z3K. 99Sibley, Benjamin A., and Sian L. Beilock. “Exercise and Working Memory: An Individual Differences Investigation.” Journal of Sport and Exercise Psychology, vol. 29, no. 6, Human Kinetics, Dec. 2007, pp. 783–791., doi:10.1123/jsep.29.6.783″.
Working memory is actually different from short-term or long-term memory. Short-term memory is simply the ability to hold information for a short amount of time. If I ask you to remember a phone number, and then ask you to repeat it back, that’s short term memory. Long-term memory is recall over — you guessed it — longer time-frames, although “long” can be as short as 30 seconds to a minute. Without getting too deep into it, it has more to do with how your brain categorizes and re-accesses the information than actual timeframes.
Working memory, however, has to do with the storage and manipulation of information, building or creating relationships between ideas, reasoning, and the like. When you’re doing mental math, or estimating the size or distance of something, you’re normally using your working memory to recall and draw comparisons to known values (unless you’ve memorized your multiplication tables). Physical activity seems to improve it.
It literally gets you high.100Goldfarb, Allan H., and Athanasios Z. Jamurtas. “Beta-Endorphin Response to Exercise.” Sports Medicine, vol. 24, no. 1, Springer Nature, July 1997, pp. 8–16., doi:10.2165/00007256-199724010-00002.
101Sparling, P. B., et al. “Exercise Activates the Endocannabinoid System.” NeuroReport, vol. 14, no. 17, Ovid Technologies (Wolters Kluwer Health), Dec. 2003, pp. 2209–2211., doi:10.1097/00001756-200312020-00015
Fun fact: the word endorphin is short for endogenous morphine, and for good reason. The chemical cocktail that your body and brain produce during and directly after performing physical activity produces a reaction that’s quite similar to real morphine — euphoria, pain reduction, feelings of well-being, the whole thing. Your brain also produces endocannabinoids (again, endogenous cannabinoids) in response to physical activity, which bind to the same receptors and produce similar feelings as smoking or ingesting cannabis.
This is true at all intensities of exercise, but especially true with very high intensity physical activity, like sprinting and heavy resistance training.
It’s not just the endorphins and endocannabinoids that provide that great post-workout feeling, either. Exercise also triggers your body and brain to produce (among other things) serotonin and the catecholamines epinephrine, norepinephrine, and dopamine, which are all mood-enhancers and/or stimulants.
A closing note about the mental benefits
Most of the benefits in this section have plenty of research that prove the effects exist, but don’t necessarily have research pinpointing why they exist or how they work, hence the sometimes vague descriptions as to mechanism of action.
The brain is a complicated system, and we still have a long way to go to understanding even basic things about why it does what it does. Blood oxygenation levels, neurotrophic factors, glucose and lipid metabolism, a huge cocktail of signaling hormones (including serotonin, dopamine, endorphins, epinephrine/adrenaline, etc), and even the placebo effect all probably play a role in one way or another, but research is still happening on how each one of these things is specifically involved in any given benefit.
The indirect benefits
You better believe there’s more. Just in case you’re not already convinced, here are a few additional ‘softer’ benefits of activity — ones that are psychological, psycho-social, or otherwise not-directly-biochemical, but still just as valuable.
It improves self-confidence, self-esteem and self-efficacy.102Sonstroem, Robert J. “Exercise and Self-Esteem.” Exercise and Sport Sciences Reviews, vol. 12, no. 1, 1984, doi:10.1249/00003677-198401000-00007″. 103Joseph, Rodney P., et al. “Physical Activity and Quality of Life among University Students: Exploring Self-Efficacy, Self-Esteem, and Affect as Potential Mediators.” Quality of Life Research, vol. 23, no. 2, Springer Nature, Aug. 2013, pp. 659–667., doi:10.1007/s11136-013-0492-8″. 104Parschau, Linda, et al. “Positive Experience, Self-Efficacy, and Action Control Predict Physical Activity Changes: A Moderated Mediation Analysis.” British Journal of Health Psychology, vol. 18, no. 2, Wiley-Blackwell, Sept. 2012, pp. 395–406., doi:10.1111/j.2044-8287.2012.02099.x”. 105Boutcher, Stephen H., et al. “The Effects of Exercise On Self-Perceptions and Self-Esteem.” Physical Activity and Psychological Well-Being, Routledge, 2003
This is another one where the research seems to imply that it works as a cyclical feedback loop: exercise improves self-esteem and self-efficacy (your perceived ability to complete a task), and improved self-efficacy also triggers an increase in physical activity.
Ultimately, this idea makes sense on its face: the more you successfully do something difficult, the more confident you are that you can do difficult things. Improvement begets more improvement, and consistent wins help you believe that you are capable in other aspects of life too, not just physical activity.
That improved self-esteem may stem from the sheer fact of consistently being active (a challenge in and of itself) or seeing improvement in your chosen discipline, or most likely both. The research also implies that improved body image is also potentially at play here — meaning that six pack abs may not be so useless after all.
It improves self-discipline.106Baumeister, Roy F., et al. “Self-Regulation and Personality: How Interventions Increase Regulatory Success, and How Depletion Moderates the Effects of Traits on Behavior.” Journal of Personality, vol. 74, no. 6, Wiley-Blackwell, Dec. 2006, pp. 1773–1802., doi:10.1111/j.1467-6494.2006.00428.x”. 107Zou, Zhiling, et al. “Aerobic Exercise As a Potential Way to Improve Self-Control after Ego-Depletion in Healthy Female College Students.” Frontiers in Psychology, vol. 7, Frontiers Media SA, Apr. 2016., doi:10.3389/fpsyg.2016.00501″. 108Muraven, Mark, et al. “Longitudinal Improvement of Self-Regulation Through Practice: Building Self-Control Strength Through Repeated Exercise.” The Journal of Social Psychology, vol. 139, no. 4, Informa UK Limited, Aug. 1999, pp. 446–457., doi:10.1080/00224549909598404″. 109Muraven, Mark. “Building Self-Control Strength: Practicing Self-Control Leads to Improved Self-Control Performance.” Journal of Experimental Social Psychology, vol. 46, no. 2, Elsevier BV, Mar. 2010, pp. 465–468., doi:10.1016/j.jesp.2009.12.011″.
Researchers use phrases like self-regulation and self-control to describe this concept, but it boils down to the core idea of being able to do what you say you’ll do, consistently.
We’re not just talking about getting yourself to the gym, either — studies show that these benefits carry over to all kinds of self-regulation-related activities.
The most outstanding of these was a 2006 study, where a group of Australian researchers showed improvement in a wide swath of self-reported self-discipline-related activities after just two months of an exercise program, including decreased smoking, alcohol and caffeine consumption, and increased healthy eating, emotional control, maintenance of household chores, attendance to commitments, and monitoring of spending.
People treat you better.110Clifford, Margaret M., and Elaine Walster. “The Effect of Physical Attractiveness on Teacher Expectations.” Sociology of Education, vol. 46, no. 2, 1973, p. 248., doi:10.2307/2112099″. 111Thorndike, E. L. “A Constant Error in Psychological Ratings.” Journal of Applied Psychology, vol. 4, no. 1, American Psychological Association (APA), 1920, pp. 25–29., doi:10.1037/h0071663″. 112Kanazawa, Satoshi, and Mary C. Still. “Is There Really a Beauty Premium or an Ugliness Penalty on Earnings?” Journal of Business and Psychology, Springer Nature, Feb. 2017., doi:10.1007/s10869-017-9489-6″.
It’s not fair, but it’s true: folks who look fit or attractive (and/or are known to be physically active) are treated better and perceived as more successful in other non-fitness pursuits. They are seen as more trustworthy, more likeable, smarter, and may even make more money.
Your are indulging some of your most fundamental biological impulses.113https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-2007-971926
When was the last time you skipped? When was the last time you saw someone frown while skipping? When was the last time you ran as fast as you could, just to do it?
Bodies evolved to move and be used. Until very recently (evolutionarily — 12,000 years or so in people time), we moved almost constantly, hunting and gathering food. Physically exerting force on objects was our only non-verbal way to interact with the world — if you include the light tapping of screens and the wiggling of a pen, it still is.
The feeling of using your body at its full capacity is downright exhilarating, and yet most of us spend 22, 23, even all 24 hours of our day basically stationary.
Be more active just because it feels good (and if it doesn’t feel good, do the work so that it does). Play flag football in a park. Turn a wrench, swing a hammer. Do a cartwheel. Because you can.
Increased physical capability is its own reward.
To paraphrase strength coach Mark Rippetoe, physical capability makes you better at most things and generally harder to kill.
Practically, this means you get to do more and be more — it gives you the mental calm to treat others better, the physical capacity to spend the afternoon playing with your kids, or hiking and enjoying the outdoors. You only get one body, and being able to use it well to get the most out of life is critical to a life well-lived.
Very few people say “I wish I would have gone fewer places and done less” on their deathbeds. Health is a gift that needs to be treasured and protected; many, many people aren’t lucky enough to even have the ability to have a pain- and exhaustion-free lifestyle. If you have it, or can regain it, spend the effort to protect it.
It reinforces other skills that have broadly-applicable benefits
This one will also serve as a conclusion, because up until this benefit, I haven’t addressed an obvious flaw with this entire article: knowing that you should be moving more and actually making the time and changing your habits so you do move more are two entirely different things.
Making activity a regular part of your life both requires and trains a variety of skills — patience, understanding the value of consistent effort, a growth mindset, the ability to change your behavior, a dual focus on the “clouds and dirt,” planning, precommitment, mental fortitude, you name it.
Creating a consistent activity practice is hard. Behavioral change is hard. Going to the gym every day (or even just 2-3 times a week) is actually a much more difficult problem than figuring out what to do when you get there. But if you’re able to become a person who exercise, you’ll necessarily master these skills — which carry over into your career, your relationships, and the rest of your life.