Physical Activity and Diabetes.

Abstract

Key Messages•Moderate to high levels of physical activity and cardiorespiratory fitness are associated with substantially lower morbidity and mortality in people with diabetes.•Both aerobic and resistance exercise are beneficial, and it is optimal to do both types of exercise. At least 150 minutes per week of aerobic exercise and at least 2 sessions per week of resistance exercise are recommended, though smaller amounts of activity still provide some health benefits.•A number of strategies that increase self-efficacy and motivation can be employed to increase physical activity uptake and maintenance, such as setting specific physical activity goals, using self-monitoring tools (pedometers or accelerometers) and developing strategies to overcome anticipated barriers.•For people with type 2 diabetes, supervised exercise programs have been particularly effective in improving glycemic control, reducing the need for noninsulin antihyperglycemic agents and insulin, and producing modest but sustained weight loss.•Habitual, prolonged sitting is associated with increased risk of death and major cardiovascular events.Key Messages for People with Diabetes•Physical activity often improves glucose control and facilitates weight loss, but has multiple other health benefits even if weight and glucose control do not change.•It is best to avoid prolonged sitting. Try to interrupt sitting time by getting up briefly every 20 to 30 minutes.•Try to get at least 150 minutes per week of aerobic exercise (like walking, bicycling or jogging).•Using a step monitor (pedometer or accelerometer) can be helpful in tracking your activity.•In addition to aerobic exercise, try to do at least 2 sessions per week of strength training (like exercises with weights or weight machines).•If you decide to begin strength training, you should ideally get some instruction from a qualified exercise specialist.•If you cannot reach these recommended levels of activity, doing smaller amounts of activity still has some health benefits. •Moderate to high levels of physical activity and cardiorespiratory fitness are associated with substantially lower morbidity and mortality in people with diabetes.•Both aerobic and resistance exercise are beneficial, and it is optimal to do both types of exercise. At least 150 minutes per week of aerobic exercise and at least 2 sessions per week of resistance exercise are recommended, though smaller amounts of activity still provide some health benefits.•A number of strategies that increase self-efficacy and motivation can be employed to increase physical activity uptake and maintenance, such as setting specific physical activity goals, using self-monitoring tools (pedometers or accelerometers) and developing strategies to overcome anticipated barriers.•For people with type 2 diabetes, supervised exercise programs have been particularly effective in improving glycemic control, reducing the need for noninsulin antihyperglycemic agents and insulin, and producing modest but sustained weight loss.•Habitual, prolonged sitting is associated with increased risk of death and major cardiovascular events. •Physical activity often improves glucose control and facilitates weight loss, but has multiple other health benefits even if weight and glucose control do not change.•It is best to avoid prolonged sitting. Try to interrupt sitting time by getting up briefly every 20 to 30 minutes.•Try to get at least 150 minutes per week of aerobic exercise (like walking, bicycling or jogging).•Using a step monitor (pedometer or accelerometer) can be helpful in tracking your activity.•In addition to aerobic exercise, try to do at least 2 sessions per week of strength training (like exercises with weights or weight machines).•If you decide to begin strength training, you should ideally get some instruction from a qualified exercise specialist.•If you cannot reach these recommended levels of activity, doing smaller amounts of activity still has some health benefits. Physical activity is defined as any bodily movement produced by skeletal muscles that requires energy expenditure (1Caspersen C.J. Powell K.E. Christenson G.M. Physical activity, exercise, and physical fitness: Definitions and distinctions for health-related research.Public Health Rep. 1985; 100: 126-131PubMed Google Scholar). Exercise is planned, structured physical activity (1Caspersen C.J. Powell K.E. Christenson G.M. Physical activity, exercise, and physical fitness: Definitions and distinctions for health-related research.Public Health Rep. 1985; 100: 126-131PubMed Google Scholar) (see Table 1 for definitions of key exercise terms used in this article.) Aerobic exercise (like walking, bicycling, swimming or jogging) involves continuous, rhythmic movements of large muscle groups, normally at least 10 minutes at a time. In this chapter, we will refer to this type of exercise as “aerobic” for simplicity, even though when performed at a very high intensity, such as with high-intensity interval training, it also involves some anaerobic metabolism. Resistance exercise involves brief repetitive exercises with weights, weight machines, resistance bands or one's own body weight (e.g. push-ups) to increase muscle strength and/or endurance. Flexibility exercise (like lower back or hamstring stretching) aims to enhance the ability to move through fuller ranges of motion. Some types of exercise, such as yoga, can incorporate elements of both resistance and flexibility exercise.Table 1Definitions of termsPhysical activityAny bodily movement produced by skeletal muscles that results in energy expenditure above resting (basal) levels. This term broadly encompasses exercise, sport and physical activities done as a part of daily living, occupation, leisure and active transport.ExercisePlanned, structured physical activity typically performed with the intent of improving health and/or fitness.Aerobic exerciseExercise that involves continuous, rhythmic movements of large muscle groups, such as walking, bicycling, swimming or jogging, normally lasting for at least 10 minutes at a time. This type of exercise depends primarily on the aerobic energy-generating processes in the body (i.e. heart, lungs, cardiovascular system and the oxidation of fuels in skeletal muscle). Moderate-intensity aerobic activities range from 3–6 metabolic equivalents (METS) and include brisk walking, dancing, light cycling, gardening and domestic chores. Vigorous-intensity activities (>6 METS) include running, climbing stairs or hill walking, fast cycling or swimming, aerobics and most competitive sports and games.Resistance exerciseBrief repetitive exercise using weights, weight machines, resistance bands or one's own body weight (e.g. push-ups) to increase muscle strength and/or endurance.Flexibility exerciseA form of activity, such as lower back or hamstring stretching, that enhances the ability of joints to move through their full range of motion.Aerobic trainingExercise training involving periods of predominantly aerobic exercise activities, such as running, cycling or swimming, performed for the purpose of enhancing cardiorespiratory fitness, performance and/or health.Resistance trainingExercise training, involving brief repetitive exercises with weights, weight machines, resistance bands or one's own body weight (e.g. push-ups) performed for the purpose of increasing muscle mass and strength. This type of exercise uses predominantly anaerobic energy-generating systems in skeletal muscle.High-intensity interval trainingA type of aerobic exercise training based on alternating between short periods of vigorous intensity exertion and periods of rest or lower-intensity exercise; commonly performed using a predominantly aerobic exercise modality, such as running or cycling.Cardiorespiratory fitnessA health-related component of physical fitness defined as the ability of the circulatory, respiratory and muscular systems to supply oxygen during sustained physical activity. Typically measured via a treadmill or cycle ergometer test and expressed as maximal oxygen uptake (VO2max) relative to body mass or in metabolic equivalents (METS).Musculoskeletal fitnessAbility of skeletal and muscular systems to perform work (exercise). Muscular strength and muscular endurance are components of musculoskeletal fitness.Cardiorespiratory enduranceAbility of the heart, lungs and circulatory system to supply oxygen to working muscles efficiently.Muscular strengthMaximal force or tension level produced by a muscle or muscle group.Muscular enduranceAbility of muscle to maintain submaximal force levels for extended periods.Physical fitnessAbility to perform occupational, recreational and daily activities without undue fatigue. A set of measureable health and skill-related attributes that include cardiorespiratory fitness, muscular strength and endurance, body composition, flexibility, balance, agility, reaction time and power.Maximum oxygen uptake (VO2max)Maximum rate of oxygen utilization during exercise.METSThe ratio of a person's working (exercising) metabolic rate to the resting metabolic rate. One MET is equivalent to the energy expended while sitting at rest.Sedentary behaviourAn “activity” that involves little or no movement, with an energy expenditure ranging between 1-1.5 METS. Examples include sitting, watching TV, working on a computer, reclining while awake and driving. Open table in a new tab Physical activity can help people with diabetes achieve a variety of goals, including increased cardiorespiratory fitness, increased vigour, improved glycemic control, decreased insulin resistance, improved lipid profile, blood pressure (BP) reduction and maintenance of weight loss (2Chudyk A. Petrella R.J. Effects of exercise on cardiovascular risk factors in type 2 diabetes: A meta-analysis.Diabetes Care. 2011; 34: 1228-1237Crossref PubMed Scopus (122) Google Scholar, 3Colberg S.R. Sigal R.J. 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Kramer C.K. et al.Physical activity advice only or structured exercise training and association with HbA1c levels in type 2 diabetes: A systematic review and meta-analysis.JAMA. 2011; 305: 1790-1799Crossref PubMed Scopus (426) Google Scholar, 7Umpierre D. Ribeiro P.A. Schaan B.D. et al.Volume of supervised exercise training impacts glycaemic control in patients with type 2 diabetes: A systematic review with meta-regression analysis.Diabetologia. 2013; 56: 242-251Crossref PubMed Scopus (73) Google Scholar, 8Liubaoerjijin Y. Terada T. Fletcher K. et al.Effect of aerobic exercise intensity on glycemic control in type 2 diabetes: A meta-analysis of head-to-head randomized trials.Acta Diabetol. 2016; 53: 769-781Crossref PubMed Scopus (19) Google Scholar), triglycerides (TG) and cholesterol (9Balducci S. Zanuso S. 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Caspersen C.J. et al.Relationship of walking to mortality among US adults with diabetes.Arch Intern Med. 2003; 163: 1440-1447Crossref PubMed Scopus (237) Google Scholar, 12Hu F.B. Stampfer M.J. Solomon C. et al.Physical activity and risk for cardiovascular events in diabetic women.Ann Intern Med. 2001; 134: 96-105Crossref PubMed Google Scholar, 13Hu G. Jousilahti P. Barengo N.C. et al.Physical activity, cardiovascular risk factors, and mortality among Finnish adults with diabetes.Diabetes Care. 2005; 28: 799-805Crossref PubMed Scopus (149) Google Scholar) and/or moderate to high cardiorespiratory fitness (16Church T.S. LaMonte M.J. Barlow C.E. et al.Cardiorespiratory fitness and body mass index as predictors of cardiovascular disease mortality among men with diabetes.Arch Intern Med. 2005; 165: 2114-2120Crossref PubMed Scopus (233) Google Scholar) are associated with reductions in cardiovascular (CV) and overall mortality. Randomized trials have also demonstrated that aerobic exercise training increases cardiorespiratory fitness in both type 1 and type 2 diabetes (17Nielsen P.J. Hafdahl A.R. Conn V.S. et al.Meta-analysis of the effect of exercise interventions on fitness outcomes among adults with type 1 and type 2 diabetes.Diabetes Res Clin Pract. 2006; 74: 111-120Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar), and slows the development of peripheral neuropathy (18Balducci S. Iacobellis G. Parisi L. et al.Exercise training can modify the natural history of diabetic peripheral neuropathy.J Diabetes Complications. 2006; 20: 216-223Abstract Full Text Full Text PDF PubMed Scopus (152) Google Scholar). A meta-analysis (6Umpierre D. Ribeiro P.A. Kramer C.K. et al.Physical activity advice only or structured exercise training and association with HbA1c levels in type 2 diabetes: A systematic review and meta-analysis.JAMA. 2011; 305: 1790-1799Crossref PubMed Scopus (426) Google Scholar) found that supervised exercise interventions improved A1C in people with type 2 diabetes when compared to no exercise comparison groups. In addition, interventions involving exercise durations of more than 150 minutes per week were associated with greater A1C reductions (mean change −0.89%) than interventions involving 150 minutes or less of exercise per week (mean change −0.36%) (6Umpierre D. Ribeiro P.A. Kramer C.K. et al.Physical activity advice only or structured exercise training and association with HbA1c levels in type 2 diabetes: A systematic review and meta-analysis.JAMA. 2011; 305: 1790-1799Crossref PubMed Scopus (426) Google Scholar). A meta-analysis of head-to-head trials comparing the effects on A1C of aerobic exercise at higher vs. lower intensity found that the interventions with higher intensity reduced A1C more than those of lower intensity (mean A1C difference −0.22%) (8Liubaoerjijin Y. Terada T. Fletcher K. et al.Effect of aerobic exercise intensity on glycemic control in type 2 diabetes: A meta-analysis of head-to-head randomized trials.Acta Diabetol. 2016; 53: 769-781Crossref PubMed Scopus (19) Google Scholar). It was unclear whether the greater benefits of higher-intensity exercise were limited to studies using high-intensity interval training (see next section on interval training). In contrast to trials in type 2 diabetes, most clinical trials evaluating exercise interventions in adults with type 1 diabetes have not demonstrated a beneficial effect of exercise on glycemic control (19Kennedy A. Nirantharakumar K. Chimen M. et al.Does exercise improve glycaemic control in type 1 diabetes? A systematic review and meta-analysis.PLoS ONE. 2013; 8 (e58861)Crossref Scopus (53) Google Scholar), but 2 recent meta-analyses found that aerobic training lowered A1C in children and youth with type 1 diabetes by 0.5% and 0.85% respectively (20MacMillan F. Kirk A. Mutrie N. et al.A systematic review of physical activity and sedentary behavior intervention studies in youth with type 1 diabetes: Study characteristics, intervention design, and efficacy.Pediatr Diabetes. 2014; 15: 175-189Crossref PubMed Scopus (25) Google Scholar, 21Quirk H. Blake H. Tennyson R. et al.Physical activity interventions in children and young people with type 1 diabetes mellitus: A systematic review with meta-analysis.Diabet Med. 2014; 31: 1163-1173Crossref PubMed Scopus (40) Google Scholar), while also lowering body mass index (BMI), TG and total cholesterol levels. A recent large cross-sectional study of 18,028 adults with type 1 diabetes reported an inverse association between physical activity levels and A1C, diabetic ketoacidosis (DKA), BMI and a number of diabetes-related complications, including dyslipidemia, hypertension, retinopathy and microalbuminuria (22Bohn B. Herbst A. Pfeifer M. et al.Impact of physical activity on glycemic control and prevalence of cardiovascular risk factors in adults with type 1 diabetes: A cross-sectional multicenter study of 18,028 patients.Diabetes Care. 2015; 38: 1536-1543Crossref PubMed Scopus (28) Google Scholar). There are no published trials evaluating the effects of exercise training on quality of life in type 1 diabetes. High-intensity interval training involves alternating between short periods of higher and lower-intensity exercise (see Exercise Prescription Examples). High-intensity interval training leads to greater gains in cardiorespiratory fitness in people with or without diabetes (23Weston K.S. Wisloff U. Coombes J.S. High-intensity interval training in patients with lifestyle-induced cardiometabolic disease: A systematic review and meta-analysis.Br J Sports Med. 2014; 48: 1227-1234Crossref PubMed Scopus (225) Google Scholar, 24Jelleyman C. Yates T. O'Donovan G. et al.The effects of high-intensity interval training on glucose regulation and insulin resistance: A meta-analysis.Obes Rev. 2015; 16: 942-961Crossref PubMed Scopus (61) Google Scholar), and improves glycemic control in some studies of people with type 2 diabetes compared to continuous moderate-intensity exercise (24Jelleyman C. Yates T. O'Donovan G. et al.The effects of high-intensity interval training on glucose regulation and insulin resistance: A meta-analysis.Obes Rev. 2015; 16: 942-961Crossref PubMed Scopus (61) Google Scholar, 25Curry M. Mehta S.P. 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To date, the risks of high-intensity interval training seem comparable to moderate-intensity continuous exercise in previously screened participants with relatively good glycemic control; however, most studies have been small and underpowered (8Liubaoerjijin Y. Terada T. Fletcher K. et al.Effect of aerobic exercise intensity on glycemic control in type 2 diabetes: A meta-analysis of head-to-head randomized trials.Acta Diabetol. 2016; 53: 769-781Crossref PubMed Scopus (19) Google Scholar). A small trial in women with type 2 diabetes (n=17) found that twice-weekly high-intensity interval training reduced abdominal fat (−8.3%) and visceral fat (−24.2%) significantly, but continuous aerobic exercise did not. Resistance training in adults with type 2 diabetes improves glycemic control (as reflected by reduced A1C), decreases insulin resistance and increases muscular strength (30Gordon B.A. Benson A.C. Bird S.R. et al.Resistance training improves metabolic health in type 2 diabetes: A systematic review.Diabetes Res Clin Pract. 2009; 83: 157-175Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar), lean muscle mass (31Ryan A.S. Hurlbut D.E. Lott M.E. et al.Insulin action after resistive training in insulin resistant older men and women.J Am Geriatr Soc. 2001; 49: 247-253Crossref PubMed Google Scholar) and bone mineral density (32Nelson M.E. Fiatarone M.A. Morganti C.M. et al.Effects of high-intensity strength training on multiple risk factors for osteoporotic fractures. A randomized controlled trial.JAMA. 1994; 272: 1909-1914Crossref PubMed Google Scholar, 33Engelke K. Kemmler W. Lauber D. et al.Exercise maintains bone density at spine and hip EFOPS: A 3-year longitudinal study in early postmenopausal women.Osteoporos Int. 2006; 17: 133-142Crossref PubMed Scopus (0) Google Scholar), leading to enhanced functional status and prevention of sarcopenia and osteoporosis. The optimal resistance training program has not been clearly established in terms of frequency, intensity, type and volume (34Ishiguro H. Kodama S. Horikawa C. et al.In search of the ideal resistance training program to improve glycemic control and its indication for patients with type 2 diabetes mellitus: A systematic review and meta-analysis.Sports Med. 2016; 46: 67-77Crossref PubMed Scopus (10) Google Scholar). The greatest impact on A1C is typically seen in studies that had participants progress to 3 sets (with approximately 8 repetitions per set) of resistance-type exercises at moderate to high intensity (i.e. the maximum weight that can be lifted 8 times while maintaining proper form), 3 times per week (35Castaneda C. Layne J.E. Munoz-Orians L. et al.A randomized controlled trial of resistance exercise training to improve glycemic control in older adults with type 2 diabetes.Diabetes Care. 2002; 25: 2335-2341Crossref PubMed Google Scholar, 36Dunstan D.W. Daly R.M. Owen N. et al.High-intensity resistance training improves glycemic control in older patients with type 2 diabetes.Diabetes Care. 2002; 25: 1729-1736Crossref PubMed Scopus (419) Google Scholar) or more (37Durak E.P. Jovanovic-Peterson L. Peterson C.M. Randomized crossover study of effect of resistance training on glycemic control, muscular strength, and cholesterol in type I diabetic men.Diabetes Care. 1990; 13: 1039-1043Crossref PubMed Google Scholar, 38Cauza E. Hanusch-Enserer U. Strasser B. et al.The relative benefits of endurance and strength training on the metabolic factors and muscle function of people with type 2 diabetes mellitus.Arch Phys Med Rehabil. 2005; 86: 1527-1533Abstract Full Text Full Text PDF PubMed Scopus (187) Google Scholar). However, significant reductions in A1C and body fat have been achieved with twice-weekly resistance exercise in combination with regular aerobic exercise (39Balducci S. Zanuso S. Nicolucci A. et al.Effect of an intensive exercise intervention strategy on modifiable cardiovascular risk factors in subjects with type 2 diabetes mellitus: A randomized controlled trial: The Italian Diabetes and Exercise Study (IDES).Arch Intern Med. 2010; 170: 1794-1803Crossref PubMed Scopus (0) Google Scholar, 40Church T.S. Blair S.N. Cocreham S. et al.Effects of aerobic and resistance training on hemoglobin A1c levels in patients with type 2 diabetes: A randomized controlled trial.JAMA. 2010; 304: 2253-2262Crossref PubMed Scopus (322) Google Scholar, 41Schwingshackl L. Missbach B. Dias S. et al.Impact of different training modalities on glycaemic control and blood lipids in patients with type 2 diabetes: A systematic review and network meta-analysis.Diabetologia. 2014; 57: 1789-1797Crossref PubMed Scopus (0) Google Scholar). The effects of resistance exercise and aerobic exercise on glycemic control are additive (42Sigal R.J. Kenny G.P. Boule N.G. et al.Effects of aerobic training, resistance training, or both on glycemic control in type 2 diabetes: A randomized trial.Ann Intern Med. 2007; 147: 357-369Crossref PubMed Google Scholar). Resistance exercise in most of these studies was carried out using weight machines and/or free weights, and these findings cannot necessarily be generalized to other types of resistance exercise, such as resistance bands or exercises utilizing one's own body weight. For example, a recent meta-analysis found that exercise training with resistance bands in people with type 2 diabetes increased strength but had no significant effect on A1C (43McGinley S.K. Armstrong M.J. Boulé N.G. et al.Effects of exercise training using resistance bands on glycaemic control and strength in type 2 diabetes mellitus: A meta-analysis of randomised controlled trials.Acta Diabetol. 2015; 52: 221-230Crossref PubMed Scopus (15) Google Scholar). The benefits of resistance exercise in type 1 diabetes are less clear, but small clinical trials suggest improved body composition and strength, enhanced insulin sensitivity and possibly modest reductions in A1C (44Yardley J.E. Hay J. Abou-Setta A.M. et al.A systematic review and meta-analysis of exercise interventions in adults with type 1 diabetes.Diabetes Res Clin Pract. 2014; 106: 393-400Abstract Full Text Full Text PDF PubMed Google Scholar). Compared to aerobic exercise, resistance exercise is associated with less hypoglycemia risk for individuals with type 1 diabetes (45Yardley J.E. Kenny G.P. Perkins B.A. et al.Resistance versus aerobic exercise: Acute effects on glycemia in type 1 diabetes.Diabetes Care. 2013; 36: 537-542Crossref PubMed Scopus (59) Google Scholar, 46Yardley J.E. Kenny G.P. Perkins B.A. et al.Effects of performing resistance exercise before versus after aerobic exercise on glycemia in type 1 diabetes.Diabetes Care. 2012; 35: 669-675Crossref PubMed Scopus (63) Google Scholar). To date, evidence for the beneficial effects of other types of exercise is not as extensive or as supportive as the evidence for aerobic and resistance exercise. Two systematic reviews found that tai chi had no effect on A1C, compared to either sham exercise or usual care in people with diabetes (47Lee M.S. Jun J.H. Lim H.J. et al.A systematic review and meta-analysis of tai chi for treating type 2 diabetes.Maturitas. 2015; 80: 14-23Abstract Full Text Full Text PDF PubMed Google Scholar, 48Yan J.H. Gu W.J. Pan L. Lack of evidence on Tai Chi-related effects in patients with type 2 diabetes mellitus: A meta-analysis.Exp Clin Endocrinol Diabetes. 2013; 121: 266-271Crossref PubMed Scopus (0) Google Scholar). Systematic reviews of yoga as an intervention for type 2 diabetes (49Innes K.E. Selfe T.K. Yoga for adults with type 2 diabetes: A systematic review of controlled trials.J Diabetes Res. 2016; 2016: 6979370Crossref PubMed Scopus (18) Google Scholar, 50Kumar V. Jagannathan A. Philip M. et al.Role of yoga for patients with type II diabetes mellitus: A systematic review and meta-analysis.Complement Ther Med. 2016; 25: 104-112Crossref PubMed Google Scholar, 51Cui J. Yan J.H. Yan L.M. et al.Effects of yoga in adults with type 2 diabetes mellitus: A meta-analysis.J Diabetes Investig. 2016; 8: 201-209Crossref PubMed Scopus (1) Google Scholar) have reported reductions in A1C. However, the quality of the studies was generally low and results were highly heterogeneous, limiting any conclusions that may be drawn (see Complementary and Alternative Medicine for Diabetes chapter, p. S154). No published study has demonstrated any impact of a pure flexibility program on metabolic control, injury risk or any diabetes-related outcome. Since osteoarthritis can be a barrier to physical activity (52Centers for Disease Control Prevention Arthritis as a potential barrier to physical activity among adults with diabetes–United States, 2005 and 2007.MMWR Morb Mortal Wkly Rep. 2008; 57: 486-489PubMed Google Scholar), water-based physic