INTRODUCTION — Physical inactivity is a major health problem worldwide, particularly in developed countries. The medical literature clearly demonstrates beneficial effects of physical activity on several health outcomes, including cardiovascular disease and all-cause mortality [1]. Although there are risks associated with exercise in some patients, the benefits outweigh the risks in most patients.
This topic will provide an overview of the benefits and risks of aerobic exercise in adults. The benefits and risks of strength training in adults, exercise physiology and exercise recommendations for children and adolescents, as well as for specific conditions, are discussed in detail elsewhere. (See "Strength training for health in adults: Terminology, principles, benefits, and risks" and "Exercise physiology" and "Physical activity and strength training in children and adolescents: An overview" and "Exercise and fitness in the prevention of atherosclerotic cardiovascular disease" and "Obesity in adults: Role of physical activity and exercise" and "Exercise in the treatment and prevention of hypertension" and "Exercise guidance in adults with diabetes mellitus" and "Exercise during pregnancy and the postpartum period".)
The medical evaluation of adults prior to beginning an exercise program and the exercise prescription are presented separately. (See "Exercise for adults: Terminology, patient assessment, and medical clearance", section on 'Medical assessment and clearance for exercise' and "Exercise prescription and guidance for adults", section on 'Prescribing an exercise program'.)
DEFINITIONS — Physical activity and exercise are not interchangeable terms [2].
●Physical activity is defined as bodily movement produced by the contraction of skeletal muscle that increases energy expenditure above the basal level. Any type of physical activity can be included (occupational, household, leisure time, and transportation) and categorized by level of intensity. (See "Exercise for adults: Terminology, patient assessment, and medical clearance", section on 'Determining exercise intensity'.)
●The term "exercise" refers to a form of physical activity that is planned, structured, repetitive, and purposeful with a main objective of improvement or maintenance of one or more components of physical fitness.
PHYSICAL INACTIVITY AND HEALTH — Physical inactivity is prevalent and associated with poor health outcomes. Despite the widespread prevalence of physical inactivity, its associated health risks, and the potential of increasing physical activity to improve health outcomes, clinicians do not routinely screen patients for physical inactivity or provide adequate counseling. In developed countries, only 13 to 34 percent of primary care patients reported receiving advice on physical activity from their primary care clinician [3-5].
●Prevalence – Worldwide, one out of every four adults is physically inactive, a proportion that is increasing [6,7]. Physical inactivity is particularly prevalent in more developed countries and among females, older persons, and those with lower incomes. In addition to lack of regular exercise, the percentage of time spent in sedentary behaviors (watching television or in front of a computer) is increasing [8-11].
In the United States, approximately one quarter of adults are sedentary, sitting for more than eight hours per day [12]. In addition, the majority of American adults do not meet national guidelines, with only 19 percent of females and 26 percent of males meeting criteria for sufficient physical activity [13,14].
●Health effects of physical inactivity/sedentary behavior – In large prospective cohort studies from several countries, sedentary behavior is associated with a variety of poor health outcomes, including increased mortality [8,15-19]. One study calculated the global attributable risk for premature mortality and estimated that physical inactivity caused 9 percent of premature deaths worldwide in 2008 [20]. A 10 percent reduction in inactivity could avert 533,000 deaths every year. Independent of physical activity levels, sedentary behavior is associated with negative health outcomes. As an example, in a 2015 meta-analysis, prolonged sedentary time was independently correlated with an increase in all-cause mortality, cardiovascular disease incidence and mortality, diabetes incidence, and cancer incidence and mortality at all levels of physical activity [21]. (See 'Mortality' below.)
●Health effects of extended sitting time – Extended sitting time appears to be an independent risk factor for mortality [21-26]. In addition to the total daily duration of sitting, the risk of mortality may be higher among those who sit for prolonged, uninterrupted periods as compared with those who sit for shorter, interrupted periods [22]. Prolonged sitting/sedentary time has also been associated with an increased risk for diabetes, cardiovascular disease, and cancer [21,23].
Replacing sitting time with physical activity has health benefits. As examples:
•In a prospective study including over 150,000 adults aged 59 to 82 years, replacing sitting time with exercise was associated with a decrease in all-cause mortality [27]. For inactive adults, replacing one hour of sitting time with a variety of nonexercise activities (eg, household chores, lawn and garden work, and daily walking outside of exercise) was also associated with decreased all-cause mortality.
•In a 2016 meta-analysis of 16 studies involving over one million individuals, daily sitting time of over eight hours per day was associated with increased all-cause mortality [26]. However, this increased risk was no longer evident among those individuals who engaged in moderate-intensity activity (35.5 metabolic equivalents [MET] for task hours per week), approximately 60 to 75 minutes per day or more.
•In a prospective study of 150,000 Australian adults aged 45 and older, an association between greater sitting time and increased mortality was found among inactive individuals. However, even among individuals with the most sitting time, the association with increased mortality was eliminated with the addition of ≥ 300 minutes per week of moderate- to high-intensity physical activity [28].
Studies evaluating interventions to reduce sitting time have reported mixed results. A 2016 systematic review concluded that there was some evidence that sit-stand desks decrease sitting time but found inconsistent evidence for interventions such as counseling or computer prompts [29].
BENEFITS OF EXERCISE — Exercise favorably impacts multiple systems and health outcomes (table 1). A graded relationship between exercise and the development of common chronic conditions (including cardiovascular disease, diabetes mellitus, chronic lung disease, chronic kidney disease, and some cancers) has been observed, such that greater exercise in midlife was associated with compression of morbidity in later years with a decreased risk of multiple chronic conditions in the last five years of life [30].
Mortality — Most data on the benefits of exercise come from observational studies. There are no high-quality, long-term, randomized trials of exercise for prevention of cardiovascular disease or death in a healthy population. Large observational studies suggest that regular exercise reduces risk of all-cause and disease-specific mortality for most individuals, including males and females, younger and older populations, and those with hypertension [1,13,31-42]. This risk reduction is seen with recreational and non-recreational physical activity and in countries with low, middle, and high incomes.
The beneficial effects of exercise appear to be dose-dependent [43,44]. However, persons who engage in as little as one to two 75-minute sessions of exercise per week (“weekend warriors”) appear to have decreased all-cause, cardiovascular, and cancer-related mortality compared with sedentary individuals [45]. The evidence also suggests that the benefits of exercise on reducing mortality may plateau after a certain activity level [46]. Doses above 100 minutes/day for moderate-intensity physical activity in healthy individuals do not appear to be associated with additional reductions in mortality rates [47].
Representative studies include:
●In a retrospective cohort study, physical activity habits were analyzed in 10,269 Harvard College alumni over 12 years [33]. Males who engaged in moderately vigorous sports activity had a 23 percent lower risk of death than those who were less active. The improvement in survival with exercise was equivalent and additive to other lifestyle measures such as smoking cessation, control of hypertension, and avoidance of obesity (figure 1). This highlights the importance of exercise given that the specific benefits of regular exercise persist despite individuals attempting to improve multiple lifestyle habits concurrently.
●Moderate levels of physical activity appear to confer a significant health benefit, although greater amounts of activity afford greater protection from premature death (figure 2) [36,43]. Progressing from lower to higher levels of physical activity has been shown to reduce overall mortality [33,35,37,39]. Vigorous exercise (at least 20 minutes three times a week) combined with regular exercise (at least 30 minutes of moderate activity most days of the week) was associated with a 50 percent decreased mortality risk in an observational study involving over 250,000 adults aged 50 to 71 years [35]. Data from the Framingham Heart Study show that moderate and high, compared with low, physical activity levels increase life expectancy for males at age 50 by 1.3 and 3.7 years, respectively; results were similar for females (1.5 and 3.5 years) [37].
●Total daily activity energy expenditure may correlate more strongly with mortality benefit than self-reported exercise intensity. Comparing mortality among individuals in the highest versus lowest tertile for activity energy expenditure in a study of 302 high-functioning volunteers (age 70 to 82 years), the hazard ratio (HR) for mortality over six years was 0.31 (95% CI 0.14-0.69); self-reported exercise intensity did not differ significantly across the energy tertiles, although frequency of paid employment and stair climbing was greater in the higher-energy groups [38].
●In an observational cohort study involving 336,560 participants stratified by high-sensitivity C-reactive protein (CRP) level, patients with regular vigorous physical activity had lower mortality compared with those who had no regular physical activity (HR 0.75; 95% CI 0.60-0.93) [40]. The reduction in mortality was less pronounced among patients with regular but less vigorous physical activity (HR 0.85; 95% CI 0.72-0.99). Similar trends were noted for cardiovascular and cancer-related mortality in these groups.
●In a longitudinal study of almost 4000 cognitively frail older adults aged 60 and older, those who were physically active had a 36 percent reduction in mortality compared with those who were inactive (95% CI 21-47) [48].
Cardiovascular disease — A number of studies have shown a strong inverse relationship between habitual exercise and the risk of coronary disease, cardiac events, and cardiovascular death for both primary and secondary prevention (figure 3) [1,49-52]. (See "Exercise and fitness in the prevention of atherosclerotic cardiovascular disease".)
Observational studies suggest that exercise may also have the following beneficial effects:
●Aerobic training induces beneficial effects on lipoproteins (eg, decrease in very low-density lipoprotein, increase in high-density lipoprotein), body composition, and aerobic capacity, as well as improves hemostatic factors associated with thrombosis. (See "Effects of exercise on lipoproteins and hemostatic factors".)
●Regular physical activity is associated with decreased levels of markers of inflammation (CRP and interleukin [IL]-6) [53,54]. (See "C-reactive protein in cardiovascular disease" and "Overview of established risk factors for cardiovascular disease", section on 'Inflammation'.)
●Long-term aerobic exercise has a beneficial effect upon systemic blood pressure [55,56]. (See "Exercise in the treatment and prevention of hypertension".)
●Exercise may reduce the risk of stroke [57-59]. (See "Exercise and fitness in the prevention of atherosclerotic cardiovascular disease" and "Overview of secondary prevention of ischemic stroke".)
Diabetes — Aerobic exercise may improve glycemic control and insulin sensitivity and may prevent the development of type 2 diabetes in high-risk groups. (See "Exercise guidance in adults with diabetes mellitus" and "Prevention of type 2 diabetes mellitus", section on 'Exercise'.)
Cancer prevention and treatment — Exercise may provide modest protection against breast, intestinal, bladder, kidney, lung, stomach, esophageal, prostate, endometrial, and pancreatic cancers [13,52,60,61]. Substantial observational data suggest that regular physical activity appears to be associated with protection from both proximal and distal colorectal cancer [62-64]. In a meta-analysis of 21 studies, there was a significant 27 percent reduced risk of proximal colon cancer when comparing the most versus the least active individuals (RR 0.73, 95% CI 0.66-0.81) [63]. An almost identical result was found for distal colon cancer (RR 0.74, 95% CI 0.68-0.80). (See "Overview of cancer prevention", section on 'Physical activity'.)
For patients treated for cancer, observational studies have reported a link between survival and exercise, with most of the data coming from survivors with breast, colorectal, or prostate cancers. In addition, interventional studies have shown a direct effect of exercise on other outcomes, including fatigue and quality of life. (See "The roles of diet, physical activity, and body weight in cancer survivors" and "Cancer-related fatigue: Treatment", section on 'Exercise'.)
Obesity — Preventing or treating obesity may lead to significant health benefits over the course of a lifetime. Compared with a weight loss diet alone, diet coupled with either exercise or exercise and resistance training is associated with a greater reduction in body fat and enhanced preservation of body lean mass, compared with weight loss diet alone.
Aerobic exercise and resistance training, even in the absence of caloric restriction, may result in weight loss and a reduction in body fat [65-67]. Long-term (20-year) follow-up of participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study found that habitual activity was associated with less weight gain at middle age, especially in females [68]. However, a 15-year longitudinal study in postmenopausal females found that a minimum of 60 minutes a day of moderate intensity activity, sustained over years, was necessary to prevent weight gain and was effective only in those whose initial body mass index (BMI) was <25 kg/m2 (normal or underweight) [69]. (See "Obesity in adults: Role of physical activity and exercise".)
Other health outcomes
●Osteoporosis – Weightbearing exercise is associated with an increase in bone mineral density in males and females. In addition, among patients with osteoporosis, exercise is associated with a decreased risk of hip fractures. (See "Prevention of osteoporosis", section on 'Physical activity' and "Overview of the management of osteoporosis in postmenopausal women", section on 'Exercise'.)
●Smoking cessation – Vigorous exercise modestly facilitates short- and long-term smoking cessation in females when combined with a cognitive-behavioral smoking cessation program [70]. Vigorous exercise also delays weight gain following smoking cessation. (See "Behavioral approaches to smoking cessation".)
●Gallstones – Physical activity is associated with a decreased risk of symptomatic cholelithiasis. (See "Gallstones: Epidemiology, risk factors and prevention", section on 'Physical activity'.)
●Cognition – Exercise has been associated with improved cognitive function in both young and older adults [71-73]. However, it is unclear whether physical activity prevents dementia and cognitive decline [74]. (See "Risk factors for cognitive decline and dementia", section on 'Lifestyle and activity' and "Prevention of dementia", section on 'Lifestyle and activity'.)
●Psychological – Regular exercise is associated with improved sleep, reduced stress and anxiety, and a lower risk of depression [13,75-77]. In one randomized trial, higher exercise energy expenditure led to greater improvement in measures of both physical and psychological quality of life [78]. (See "Insufficient sleep: Evaluation and management", section on 'Management' and "Complementary and alternative treatments for anxiety symptoms and disorders: Physical, cognitive, and spiritual interventions", section on 'Physical exercise'.)
●Kidney function – Regular exercise may reduce the decline in kidney function seen with normal aging (see "The aging kidney", section on 'GFR declines with normal aging'). In a randomized trial including over 1600 sedentary older adults, participation in a regular, moderate-intensity exercise program reduced the degree of decline in kidney function, measured by eGFRcystatin C (0.96 mL/min/1.73 m2, 95% CI 0.02-1.91), as well the risk of rapid decline in kidney function (odds ratio [OR] 0.79, 95% CI, 0.65-0.97) at two years compared with receiving only an education intervention [79].
Additionally, regular physical activity is associated with fewer falls and fall-related injuries in older adults and, in pregnant individuals, a reduced risk of excessive weight gain, gestational diabetes, and post-partum depression [13]. (See "Falls: Prevention in community-dwelling older persons", section on 'Exercise' and "Gestational weight gain" and "Gestational diabetes mellitus: Glucose management and maternal prognosis", section on 'Exercise' and "Exercise during pregnancy and the postpartum period".)
RISKS OF EXERCISE — The benefits of physical activity far outweigh the possible associated risks in the majority of patients [2]. Musculoskeletal injury is the most common risk of exercise. More serious but much less common risks include arrhythmia, sudden cardiac arrest, and myocardial infarction (MI).
One study analyzed available data from several exercise trials in diverse patient populations (mostly sedentary at baseline and some with identified cardiovascular risk factors) and found that exercise was associated with an adverse change in one or more metabolic risk factors for cardiovascular disease in 8 to 13 percent of participants, while a similar proportion of participants experienced an unusually strong positive change in these risk factors [80]. Based upon measurements in a small sample of controls, the authors felt that these changes were larger than would be expected just with random variation; however, random variation still appears to be a likely explanation for the results. The study did not look at actual cardiovascular event rates.
Any potential risks of routine exercise do not outweigh its benefits, in the absence of a contraindication to exercise. (See "Exercise prescription and guidance for adults", section on 'Contraindications to exercise'.)
Musculoskeletal injury — Those who engage in sports activities run a higher risk of incurring minor injury; however, people who do not participate in regular exercise are more likely to incur more severe injuries when engaging in such activity [81].
Acute strains and tears, inflammation of various types, chronic strain, stress fractures, traumatic fractures, nerve palsies, tendonitis, and bursitis all may occur during or as result of physical activity [82,83]. Musculoskeletal injuries vary based on a variety of factors, including age (child, adolescent, adult, older adult), type of activity (eg, contact sports, high-impact exercises, walking), and intensity.
Many of the musculoskeletal injuries are secondary to overuse [84,85]. Two of the most common risk factors for injury among runners, for example, are longer running distances and history of previous injury [85]. (See "Musculoskeletal injury in children and skeletally immature adolescents: Overview of treatment principles for nonoperative injuries" and "Overview of running injuries of the lower extremity".)
Arrhythmia — There is an increased risk of arrhythmia during exercise in patients with underlying heart disease or a prior history of arrhythmia. Exercise training may reduce atrial and ventricular arrhythmia risk by increasing myocardial oxygen supply and reducing sympathetic nervous system activity. (See "Athletes with arrhythmias: Clinical manifestations and diagnostic evaluation" and "Athletes: Overview of sudden cardiac death risk and sport participation".)
A separate issue, ventricular and atrial arrhythmias occurring during exercise testing, is discussed elsewhere. (See "Prognostic features of stress testing in patients with known or suspected coronary disease", section on 'Ventricular arrhythmias' and "Prognostic features of stress testing in patients with known or suspected coronary disease", section on 'Atrial arrhythmias'.)
Sudden cardiac death — Sudden cardiac death (SCD) is rare but may occur during physical or sexual activity [86,87]. The risk of SCD in athletes is discussed separately. (See "Athletes: Overview of sudden cardiac death risk and sport participation".)
The increase in risk is seen in both males and females. In the Physicians' Health Study of 21,481 males followed for 12 years, the absolute risk of SCD during any one episode of vigorous exercise was low (one death per 1.51 million episodes of exercise) [88]. In the Nurses' Health Study of 69,693 females, the absolute risk was even lower, with one death per 36.5 million hours of exertion [89]. The risk of cardiac arrest is less or may not be increased at all if there is habitual, heavy leisure-time physical activity, as noted in both the Physicians' Health Study and the Nurses' Health Study [88,89].
Mechanisms of SCD in those who exercise include coronary artery disease, arrhythmias (especially ventricular tachycardia and ventricular fibrillation), structural heart disease, and myocarditis [90]. Causes of SCD in people who exercise can be divided according to age [86]. Among those over age 35 years, SCD is generally a result of atherosclerotic coronary artery disease; among younger individuals, it is more likely due to congenital abnormalities such as hypertrophic cardiomyopathy, coronary anomalies, or myocarditis. (See "Overview of sudden cardiac arrest and sudden cardiac death", section on 'Exercise'.)
Because the increase in risk of SCD during or just after activity is low, the long-term health benefits of exercise outweigh the risks in patient with and without established heart disease [91].
Myocardial infarction — Physical or sexual activity is associated with a temporary increase in the risk of having an MI, particularly among those who exercise infrequently and have multiple cardiac risk factors [87,91,92]. In a study of 1194 patients who completed a survey within two weeks of having an MI, physical exertion at the onset of infarction was reported in 7.1 percent of the case patients compared with 3.9 percent of matched controls prior to the onset of the control event [92]. The adjusted relative risk (RR) of having engaged in strenuous physical activity at the onset of the MI was 2.1; the RR was much higher in patients who performed regular exercise less than four times per week and compared with those who exercised four or more times per week (RR 6.9 versus 1.3).
Although patients with coronary disease are more likely to have an MI at the time they are participating in strenuous exercise than when they are not, patients with coronary disease who exercise are overall less likely to have an MI than those with coronary disease who do not exercise. A 12-year prospective study of 2400 males found that those who were in the highest third of vigorous physical activity, compared with the lowest third, experienced a decreased risk of MI, regardless of the presence of symptomatic, asymptomatic (electrocardiogram [ECG] changes consistent with ischemia), or no coronary heart disease at baseline (hazard ratio [HR] 0.71, 0.42, and 0.60, respectively) [93].
Rhabdomyolysis — Subclinical myoglobinemia, myoglobinuria, and elevation of creatine kinase (CK) are common following physical exertion [94]. The CK level can rise several-fold, particularly after intense exercise for extended periods of time (eg, marathon running). Rhabdomyolysis may occur following extreme exertion in individuals with normal muscles when the energy supply to muscle is insufficient to meet demands. Severe complications of rhabdomyolysis include renal failure, electrolyte abnormalities (eg, hyperkalemia, metabolic acidosis), and compartment syndrome. (See "Rhabdomyolysis: Clinical manifestations and diagnosis".)
Massive rhabdomyolysis may arise with marked physical exertion, particularly when the following risk factors are present [95,96]:
●The individual is physically untrained.
●Exertion occurs in extremely hot, humid conditions. (See "Severe nonexertional hyperthermia (classic heat stroke) in adults".)
●Normal heat loss through sweating is impaired, such as via the use of anticholinergic medications or heavy football equipment.
●An individual with a sickle cell syndrome exercises at high altitude, a setting in which the decreased partial pressure of oxygen causes erythrocyte sickling with subsequent vascular occlusion and muscle ischemia. (See "Overview of compound sickle cell syndromes".)
●Electrolytes abnormalities are present, particularly hypokalemia, which can be partly caused by potassium loss from sweating. (See "Rhabdomyolysis: Epidemiology and etiology", section on 'Electrolyte disorders'.)
●Metabolic or inflammatory myopathies are present. (See "Approach to the metabolic myopathies" and "Clinical manifestations of dermatomyositis and polymyositis in adults".)
However, rhabdomyolysis can also occur in trained individuals following physical exertion in the absence of these risk factors [97,98].
Bronchoconstriction — Exercise-induced bronchoconstriction occurs in the majority of patients with current symptomatic asthma [99]. The magnitude of exercise-induced bronchoconstriction is correlated with the degree of airway hyperresponsiveness.
Improving a patient's cardiovascular fitness reduces the minute ventilation required for a given level of exercise, thereby decreasing the stimulus for bronchoconstriction. Thus, regular, long-term exercise may be helpful in preventing the onset of exercise-induced bronchoconstriction. (See "Exercise-induced bronchoconstriction".)
Other effects — Hyperthermia, hypothermia, and dehydration are potential preventable risks of physical activity. Heat-related risks range from mild fatigue to death [100]. Dehydration may be a problem itself or can be related to hyperthermia.
Intense exercise can lead to amenorrhea and infertility, particularly in females with low body weight. The "female athlete triad" consists of disordered eating, amenorrhea, and osteoporosis. This is commonly seen in younger individuals, especially those who exercise regularly and intensely. (See "Functional hypothalamic amenorrhea: Pathophysiology and clinical manifestations".)
Urticaria and anaphylaxis can rarely occur with exercise. (See "Exercise-induced anaphylaxis: Clinical manifestations, epidemiology, pathogenesis, and diagnosis".)
Exercise-associated hyponatremia primarily occurs in athletes participating in aerobic (endurance) events, such as marathons (42.2 km), triathlons (3.8 km swim, 180 km cycling, and 42.2 km running), and ultra-distance (100 km) races. (See "Exercise-associated hyponatremia".)
Exercise has acute and chronic effects on drug pharmacokinetics [101], but the clinical implications of these changes are unclear. Pending additional information, these observations should not be used to dissuade patients from exercising.
SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Exercise in adults".)
INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Basics topics (see "Patient education: Exercise and movement (The Basics)" and "Patient education: Physical activity for people with arthritis (The Basics)" and "Patient education: Rhabdomyolysis (The Basics)")
●Beyond the Basics topics (See "Patient education: Exercise (Beyond the Basics)" and "Patient education: Arthritis and exercise (Beyond the Basics)".)
SUMMARY AND RECOMMENDATIONS
●Health effects of physical inactivity and sedentary behavior – Physical inactivity is a major health problem worldwide, particularly in developed countries and among females, older persons, and those with lower incomes. (See 'Physical inactivity and health' above.)
Sedentary behavior is prevalent and is also associated with a variety of poor health outcomes, including increased mortality and increased risk for diabetes and cardiovascular disease. Some of these risks do not appear to be mitigated by participation in physical activity, although adding moderate- to vigorous-intensity physical activity may reduce the association with increased all-cause mortality.
●Health benefits of exercise – Moderate and/or vigorous exercise is associated with several beneficial health outcomes, including improved bone health and decreased risk of obesity, coronary heart disease, stroke, certain types of cancer, and all-cause mortality (table 1 and figure 1 and figure 2). Exercise may also increase the likelihood of stopping tobacco use, improve cognitive function, decrease the risk of falls and fall related injuries in older adults, and reduce stress, anxiety, and depression. (See 'Benefits of exercise' above.)
●Potential risks of exercise – Musculoskeletal injury is the most common risk of exercise. More serious, but less common, risks include arrhythmia, sudden cardiac arrest, and myocardial infarction (MI). However, the benefits of exercise outweigh the potential risks. (See 'Risks of exercise' above.)
