Review
Exercise management in type 1 diabetes: a consensus statement

https://doi.org/10.1016/S2213-8587(17)30014-1Get rights and content

Summary

Type 1 diabetes is a challenging condition to manage for various physiological and behavioural reasons. Regular exercise is important, but management of different forms of physical activity is particularly difficult for both the individual with type 1 diabetes and the health-care provider. People with type 1 diabetes tend to be at least as inactive as the general population, with a large percentage of individuals not maintaining a healthy body mass nor achieving the minimum amount of moderate to vigorous aerobic activity per week. Regular exercise can improve health and wellbeing, and can help individuals to achieve their target lipid profile, body composition, and fitness and glycaemic goals. However, several additional barriers to exercise can exist for a person with diabetes, including fear of hypoglycaemia, loss of glycaemic control, and inadequate knowledge around exercise management. This Review provides an up-to-date consensus on exercise management for individuals with type 1 diabetes who exercise regularly, including glucose targets for safe and effective exercise, and nutritional and insulin dose adjustments to protect against exercise-related glucose excursions.

Introduction

Despite tremendous advances since the discovery of insulin almost 100 years ago, management of type 1 diabetes remains challenging.1, 2 The majority of patients living with type 1 diabetes do not have a healthy bodyweight (about 60% are overweight or obese), about 40% have hypertension, about 60% have dyslipidaemia,3 and most do not engage in enough regular physical activity.4 Regular exercise can help patients achieve several goals: it improves the cardiovascular disease risk profile in paediatric patients5 and reduces HbA1c by about 0·3% in the paediatric population.6 Body composition, cardiorespiratory fitness, endothelial function, and blood lipid profile (ie, triglycerides and total cholesterol) all improve with regular physical activity in children and young people with type 1 diabetes.6 These cardiometabolic improvements are all important, given that cardiovascular disease is the leading cause of morbidity and mortality in young people with type 1 diabetes.7, 8 In adults with type 1 diabetes, both retinopathy and microalbuminuria are less common in those who are physically active than in those who are not.9 Active adults with type 1 diabetes tend to have better chance of achieving their HbA1c and blood pressure targets, and a healthier BMI, than do inactive patients.3 Regular exercise also decreases total daily insulin needs.10 Having a high exercise capacity in adulthood is associated with a reduced risk of coronary artery disease, myocardial ischaemia, and stroke, regardless of whether a person has diabetes or not.11 In a large cross-sectional study of 18 028 adults with type 1 diabetes,3 patients who were categorised as being most physically active (exercising two or more times per week) had better HbA1c concentrations, a more favourable BMI, less dyslipidaemia and hypertension, and fewer diabetes-related complications (retinopathy and microalbuminuria) than those who were less habitually active. The study also showed that patients with type 1 diabetes who are more active tend to have less diabetic ketoacidosis and a reduced risk of developing severe hypoglycaemia with coma.3 However, older women who are physically active have higher rates of severe hypoglycaemia (with coma) than those who are inactive.3 Several barriers to exercise might exist, including a fear of hypoglycaemia, loss of glycaemic control, insufficient time, access to facilities, an absence of motivation, issues around body image, and a general scarcity of knowledge around exercise management.12, 13, 14

For all adults living with diabetes, including those living with type 1 diabetes, 150 min of accumulated physical activity is recommended each week, with no more than two consecutive days of no physical activity.15 Resistance exercise is also recommended two to three times a week.15 Getting this much exercise is difficult for many patients; results from a large cross-sectional study showed that less than 20% of patients manage to do aerobic exercise more than two times per week, and about 60% of patients do no structured exercise at all.3 For children and young people with diabetes, at least 60 min of physical activity should be done per day.16 Physical inactivity and prolonged sitting times increase gradually with age and are linked to high HbA1c concentrations in young people with type 1 diabetes.17 Physical inactivity appears to be more common in women than in men with type 1 diabetes.3

Regular exercise should be encouraged and supported by health-care professionals for many reasons, but primarily because the overall cardiometabolic benefits outweigh the immediate risks if certain precautions are taken. In this Review, the basic categories of exercise are described from a physiological perspective, as are the starting points for nutritional and insulin dose adjustments to keep patients in a targeted glycaemic range. This Review summarises our consensus on the available strategies that help incorporate exercise safely into the daily management plan for those adults with type 1 diabetes who are regularly engaging in exercise, sports, or competitive events. We hope these new recommendations for exercise management will improve glycaemic control and encourage more individuals with type 1 diabetes to increase their physical activity.

Section snippets

Modalities of exercise

An understanding of the metabolic and neuroendocrine responses to the various types of exercise done by people with type 1 diabetes is essential for determination of appropriate nutritional and insulin management strategies. Exercise is generally classified as aerobic or anaerobic, depending on the predominant energy systems used to support the activity, although most exercise activities include a combination of energy systems. Aerobic exercise (eg, walking, cycling, jogging, and swimming)

Exercise goals and glycaemic targets

Individuals with type 1 diabetes should engage in exercise for various health reasons. The evidence on whether regular exercise improves metabolic control in adults with type 1 diabetes is somewhat scarce,20, 54 although exercise appears to be helpful in young people with type 1 diabetes.6 Exercise readiness questionnaires, such as Physical Activity Readiness Medical Examination (ePARmed-X+) and Physical Activity Readiness Questionnaire for Everyone (PAR-Q+), are available online for adults

Contraindications and cautions for exercise

Although few exercise restrictions should be placed on patients, some considerations are important and are highlighted below.

Goals for nutritional management

Nutritional management for people with type 1 diabetes should incorporate strategies that optimise glycaemic control while promoting long-term health.66 The main strategies around nutrition for exercise and sport discussed in this section primarily aim to maximise athletic performance and are based largely on studies done in highly trained healthy individuals without diabetes,59 with few studies done in people with type 1 diabetes. Application of these strategies to people with type 1 diabetes

Recommendations for management of glycaemia

Blood glucose responses to the various forms and intensities of exercise show high variability between and within individuals (figure 1). Glycaemic management is therefore based on frequent glucose monitoring, adjustments to both basal and bolus insulin dosing, and consumption of carbohydrates during and after exercise. These recommendations are intended to serve as a starting point for insulin adjustments and carbohydrate intake that can then be individualised (figure 2).

Clinical management

Emerging tools for exercise management

Several treatment regimens exist for people with type 1 diabetes. Continuous subcutaneous insulin infusion offers better flexibility in basal insulin adjustments and management of exercise-associated hyperglycaemia than other methods of insulin delivery.117 Continuous subcutaneous insulin infusion is associated with reduced hyperglycaemia after exercise compared with multiple daily insulin injections,112 but can create frustrating challenges for sports that might require disconnection of the

Conclusion

Regular physical activity should be a routine objective for patients with type 1 diabetes, for various health and fitness reasons. Considerable challenges remain for people with type 1 diabetes, and their health-care team, in management of exercise and sports. Several small observational studies and a few clinical trials have been published to date that help to inform the consensus recommendations presented here. More studies are needed to determine how to best prevent exercise-associated

Search strategy and selection criteria

We searched PubMed and other relevant biomedical databases for articles containing the terms “type 1 diabetes” or “insulin-dependent diabetes” and “exercise” or “physical activity”, published between January, 1990, and July, 2016, filtered for studies done in human beings, and restricted to English language publications. Additional searches were done with the following terms for various subtopics within this Review: “nutrition”, “dietary carbohydrate”, “dietary protein”, “glycaemic index”,

References (125)

  • L Bally et al.

    Accuracy of continuous glucose monitoring during differing exercise conditions

    Diabetes Res Clin Pract

    (2016)
  • S Mayor

    Insulin pumps improve glucose control in children with type 1 diabetes, study finds

    BMJ

    (2015)
  • JA McKnight et al.

    Glycaemic control of Type 1 diabetes in clinical practice early in the 21st century: an international comparison

    Diabet Med J Br Diabet Assoc

    (2015)
  • B Bohn 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)
  • A Herbst et al.

    Impact of physical activity on cardiovascular risk factors in children with type 1 diabetes: a multicenter study of 23,251 patients

    Diabetes Care

    (2007)
  • H Quirk et al.

    Physical activity interventions in children and young people with type 1 diabetes mellitus: a systematic review with meta-analysis

    Diabet Med J Br Diabet Assoc

    (2014)
  • RG Miller et al.

    A contemporary estimate of total mortality and cardiovascular disease risk in young adults with type 1 diabetes: the Pittsburgh Epidemiology of Diabetes Complications Study

    Diabetes Care

    (2016)
  • M Katz et al.

    Challenges and opportunities in the management of cardiovascular risk factors in youth with type 1 diabetes: lifestyle and beyond

    Curr Diab Rep

    (2015)
  • M Chimen et al.

    What are the health benefits of physical activity in type 1 diabetes mellitus? A literature review

    Diabetologia

    (2012)
  • B Pierre-Louis et al.

    Exercise capacity as an independent risk factor for adverse cardiovascular outcomes among nondiabetic and diabetic patients

    Arch Med Sci AMS

    (2014)
  • AS Brazeau et al.

    Barriers to physical activity among patients with type 1 diabetes

    Diabetes Care

    (2008)
  • N Lascar et al.

    Attitudes and barriers to exercise in adults with type 1 diabetes (T1DM) and how best to address them: a qualitative study

    PLoS One

    (2014)
  • SR Colberg et al.

    Physical activity/exercise and diabetes: a position statement of the American Diabetes Association

    Diabetes Care

    (2016)
  • K Robertson et al.

    Exercise in children and adolescents with diabetes

    Pediatr Diabetes

    (2014)
  • A Galler et al.

    Associations between media consumption habits, physical activity, socioeconomic status, and glycemic control in children, adolescents, and young adults with type 1 diabetes

    Diabetes Care

    (2011)
  • RB Batacan et al.

    Effects of high-intensity interval training on cardiometabolic health: a systematic review and meta-analysis of intervention studies

    Br J Sports Med

    (2016)
  • W Mitranun et al.

    Continuous vs interval training on glycemic control and macro- and microvascular reactivity in type 2 diabetic patients

    Scand J Med Sci Sports

    (2014)
  • RC Camacho et al.

    Glucoregulation during and after exercise in health and insulin-dependent diabetes

    Exerc Sport Sci Rev

    (2005)
  • T Ploug et al.

    Increased muscle glucose uptake during contractions: no need for insulin

    Am J Physiol

    (1984)
  • RH Coker et al.

    Glucoregulation during exercise : the role of the neuroendocrine system

    Sports Med Auckl NZ

    (2005)
  • MC Venables et al.

    Determinants of fat oxidation during exercise in healthy men and women: a cross-sectional study

    J Appl Physiol

    (2005)
  • LJ van Loon et al.

    The effects of increasing exercise intensity on muscle fuel utilisation in humans

    J Physiol

    (2001)
  • AJ Fahey et al.

    The effect of a short sprint on postexercise whole-body glucose production and utilization rates in individuals with type 1 diabetes mellitus

    J Clin Endocrinol Metab

    (2012)
  • AR Harmer et al.

    High-intensity training improves plasma glucose and acid-base regulation during intermittent maximal exercise in type 1 diabetes

    Diabetes Care

    (2007)
  • L Bally et al.

    Exercise-associated glucose metabolism in individuals with type 1 diabetes mellitus

    Curr Opin Clin Nutr Metab Care

    (2015)
  • A Mallad et al.

    Exercise effects on postprandial glucose metabolism in type 1 diabetes: a triple tracer approach

    Am J Physiol Endocrinol Metab

    (2015)
  • KN Frayn et al.

    Regulation of human subcutaneous adipose tissue blood flow

    Int J Obes

    (2014)
  • SA McAuley et al.

    Insulin pump basal adjustment for exercise in type 1 diabetes: a randomised crossover study

    Diabetologia

    (2016)
  • MJ Tansey et al.

    The effects of aerobic exercise on glucose and counterregulatory hormone concentrations in children with type 1 diabetes

    Diabetes Care

    (2006)
  • MC Riddell et al.

    Glucose ingestion matched with total carbohydrate utilization attenuates hypoglycemia during exercise in adolescents with IDDM

    Int J Sport Nutr

    (1999)
  • F García-García et al.

    Quantifying the acute changes in glucose with exercise in type 1 diabetes: a systematic review and meta-analysis

    Sports Med

    (2015)
  • RA Al Khalifah et al.

    Association of aerobic fitness level with exercise-induced hypoglycaemia in type 1 diabetes

    Diabet Med

    (2016)
  • AR Harmer et al.

    Sprint training increases muscle oxidative metabolism during high-intensity exercise in patients with type 1 diabetes

    Diabetes Care

    (2008)
  • E Zander et al.

    Muscular exercise in type I-diabetics. I. Different metabolic reactions during heavy muscular work in dependence on actual insulin availability

    Exp Clin Endocrinol

    (1983)
  • M Berger et al.

    Metabolic and hormonal effects of muscular exercise in juvenile type diabetics

    Diabetologia

    (1977)
  • JE Yardley et al.

    Resistance versus aerobic exercise: acute effects on glycemia in type 1 diabetes

    Diabetes Care

    (2013)
  • D Turner et al.

    Impact of single and multiple sets of resistance exercise in type 1 diabetes

    Scand J Med Sci Sports

    (2015)
  • KJ Guelfi et al.

    Effect of intermittent high-intensity compared with continuous moderate exercise on glucose production and utilization in individuals with type 1 diabetes

    Am J Physiol Endocrinol Metab

    (2007)
  • JE Yardley et al.

    Effects of performing resistance exercise before versus after aerobic exercise on glycemia in type 1 diabetes

    Diabetes Care

    (2012)
  • L Bally et al.

    Metabolic and hormonal response to intermittent high-intensity and continuous moderate intensity exercise in individuals with type 1 diabetes: a randomised crossover study

    Diabetologia

    (2016)
  • Cited by (580)

    View all citing articles on Scopus
    View full text