Exercise and Diabetes Control: A Winning Combination

Sheri R. Colberg, PhD; David P. Swain, PhD

Sports Med 2000 Mar;29(3):147-51
Physical activity and the prevention of type 2 diabetes mellitus: how much for how long?
Kriska A
Graduate School of Public Health, Department of Epidemiology, University of Pittsburgh, Pennsylvania 15261, USA.
From observational studies to clinical trials in a variety of populations and age groups, evidence is mounting in support of the hypothesis that physical activity plays a significant role in the prevention of type 2 diabetes mellitus. Based on the current findings, it is likely that physical activity can reduce the risk of diabetes mellitus development. What is less clear is how much physical activity is necessary, and for how long. Obviously, we are more likely to see the anticipated physiological changes if we maximise the dose. Yet, although maximal is better from a physiological point of view, we 'in the trenches' have also recognised the fact that a sedentary individual will most likely not continue to undergo a high intensity activity exercise regimen. In contrast, evidence is mounting regarding long term compliance to moderate levels of activity, which appear to be easier to adopt in one's lifestyle and are less likely to result in injury. More importantly, there appear to be beneficial changes in insulin sensitivity and glucose tolerance in the sedentary individual who incorporates moderate levels of activity such as walking into the their lifestyle, although the onset of beneficial metabolic changes appear to occur much more slowly and less dramatically than what occurs with a high intensity regimen. Even if activity is shown to be beneficial, we are faced with the challenge of reaching the sedentary individuals who would most likely benefit from an increase in physical activity in the first place. This task is a difficult one because of the difficulty in quantifying the sum total of an entire day's worth of movement, rather than that of a few relatively higher intensity leisure activities. What is needed is a measure or combination of measures of physical activity that are simple to use, relatively inexpensive, and adequately capture the subtle changes in physical activity through the day that we are encouraging. It is unlikely that the protective nature of a physically active lifestyle in preventing diabetes mellitus will have a lasting impact once a switch to a sedentary way of life is made. Therefore, from a public health viewpoint, long term commitments to increased activity are required. This is the ultimate challenge.

Diabet Med 2000 Jan;17(1):53-8
Leisure-time physical activity at weekends and the risk of Type 2 diabetes mellitus in Japanese men: the Osaka Health Survey.
Okada K, Hayashi T, Tsumura K, Suematsu C, Endo G, Fujii S
Medical Center for Employees' Health, Osaka Gas Co. Ltd, Japan.
AIMS: To investigate association between leisure-time physical activity at weekends and the risk of developing Type 2 diabetes mellitus (DM). METHODS: Prospective examination of 6,013 Japanese men aged 35-60 years who were free of DM, impaired fasting glycaemia, or hypertension at study entry. Type 2 DM was defined by a fasting plasma glucose level > or = 7.0 mmol/l or a 2-h post-load plasma glucose level > or =11.1 mmol/l. Data on physical activity obtained from questionnaires consisted of overall leisure-time physical activity weekly and leisure-time physical activity at weekends. RESULTS: During the 59,966 person-years follow-up, 444 cases developed Type 2 DM. Regular physical exercise at least once a week was associated with a reduced risk of Type 2 DM. After adjustments for age, body mass index, daily alcohol consumption, smoking habits, blood pressure levels and a parental history of Type 2 DM, men who engaged in regular physical exercise at least once a week had a relative risk of Type 2 DM of 0.75 (95% CI, 0.61-0.93) compared with men engaging in exercise less often. Even vigorous activity only once a week at weekends was associated with a reduced risk of Type 2 DM. Men who engaged in vigorous activity at least once a week at weekends had a multiple-adjusted relative risk of Type 2 DM of 0.55 (95% CI, 0.35-0.88) compared with sedentary men. CONCLUSIONS: Regular physical exercise at least once a week and vigorous activity even only once a week at weekends are associated with a decreased risk of Type 2 DM.

Am J Public Health 2000 Jan;90(1):134-8
Physical activity and incident diabetes mellitus in postmenopausal women.
Folsom AR, Kushi LH, Hong CP
Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis 55454, USA. folsom@epi.umn.edu
OBJECTIVES: This study determined whether the incidence of diabetes is reduced among physically active older women. METHODS: We assessed physical activity by mailed questionnaire and 12-year incidence of diabetes (ostensibly type 2 diabetes) in a cohort of 34257 women aged 55 to 69 years. RESULTS: After adjustment for age, education, smoking, alcohol intake, estrogen use, dietary variables, and family history of diabetes, women who reported any physical activity had a relative risk of diabetes of 0.69 (95% confidence interval = 0.63, 0.77) compared with sedentary women. CONCLUSIONS: These findings suggest that physical activity is important for type 2 diabetes prevention among older women.

Diabetes Care 1999 Nov;22(11):1904-5
Physical activity and competitive sports in children and adolescents with type 1 diabetes.
Raile K, Kapellen T, Schweiger A, Hunkert F, Nietzschmann U, Dost A, Kiess W
Publication Types:
Letter

JAMA 1999 Oct 20;282(15):1433-9 [Texto completo]
Walking compared with vigorous physical activity and risk of type 2 diabetes in women: a prospective study.
Hu FB, Sigal RJ, Rich-Edwards JW, Colditz GA, Solomon CG, Willett WC, Speizer FE, Manson JE
Department of Nutrition, Harvard School of Public Health, Boston, Mass 02115, USA. Frank.hu@channing.harvard.edu
CONTEXT: Although many studies suggest that physical activity may reduce risk of type 2 diabetes, the role of moderate-intensity activity such as walking is not well understood. OBJECTIVES: To examine the relationship of total physical activity and incidence of type 2 diabetes in women and to compare the benefits of walking vs vigorous activity as predictors of subsequent risk of type 2 diabetes. DESIGN AND SETTING: The Nurses' Health Study, a prospective cohort study that included detailed data for physical activity from women surveyed in 11 US states in 1986, with updates in 1988 and 1992. PARTICIPANTS: A total of 70,102 female nurses aged 40 to 65 years who did not have diabetes, cardiovascular disease, or cancer at baseline (1986). MAIN OUTCOME MEASURE: Risk of type 2 diabetes by quintile of metabolic equivalent task (MET) score, based on time spent per week on each of 8 common physical activities, including walking. RESULTS: During 8 years of follow-up (534, 928 person-years), we documented 1419 incident cases of type 2 diabetes. After adjusting for age, smoking, alcohol use, history of hypertension, history of high cholesterol level, and other covariates, the relative risks (RRs) of developing type 2 diabetes across quintiles of physical activity (least to most) were 1.0, 0.77, 0.75, 0.62, and 0.54 (P for trend <.001); after adjusting for body mass index (BMI), RRs were 1.0, 0.84, 0.87, 0.77, and 0.74 (P for trend = .002). Among women who did not perform vigorous activity, multivariate RRs of type 2 diabetes across quintiles of MET score for walking were 1.0, 0.91,0.73, 0.69, and 0.58 (P for trend <.001). After adjusting for BMI, the trend remained statistically significant (RRs were 1.0, 0.95, 0.80, 0.81, 0.74; P for trend = .01). Faster usual walking pace was independently associated with decreased risk. Equivalent energy expenditures from walking and vigorous activity resulted in comparable magnitudes of risk reduction. CONCLUSIONS: Our data suggest that greater physical activity level is associated with substantial reduction in risk of type 2 diabetes, including physical activity of moderate intensity and duration.

Prim Care 1999 Dec;26(4):857-68
Nutrition management and physical activity as treatments for diabetes.
Wheeler ML
Research Dietetics, Diabetes Research and Training Center, Indiana University
School of Medicine, Indianapolis, Indiana 46202, USA. mlwheele@iupui.edu
Diabetes is essentially a self-management disease in which patients must learn to integrate blood glucose monitoring with nutrition management and physical activity and, if needed, oral agents or insulin. This almost always requires behavior change. The American Diabetes Association diet is no longer a meaningful prescription, because recommendations are now based on individualized nutrition assessment and treatment goals. Physical activity recommendations, as an adjunct to nutrition management, should also be individualized. Using a team approach, focusing on individualization of nutrition management and physical activity, applying behavior change concepts, and providing frequent follow-up can improve self-management and result in improved metabolic control. Primary care practitioners are in a unique position to oversee this process.

Publication Types:
Review
Review, tutorial

Diabetes Care 1999 May;22(5):706-12
Correlates of physical activity in a sample of older adults with type 2 diabetes.
Hays LM, Clark DO
Indiana University Center for Aging Research, Regenstrief Institute for Health Care, Indianapolis 46202, USA. lmays@indiana.edu
OBJECTIVE: Physical activity is integral to the management of type 2 diabetes. Unfortunately, the majority of adults with type 2 diabetes do not regularly engage in physical activity. The purpose of this study was to assess physical activity behavior and its correlates (i.e., physical activity knowledge, barriers, and performance and outcome expectations) in older adults with type 2 diabetes. RESEARCH DESIGN AND METHODS: A subgroup of 260 adults with type 2 diabetes was identified from a larger stratified random sample of adults aged > or = 55 years. Participants completed an interviewer-administered survey designed from focus group findings and social learning theory. RESULTS: The majority of the respondents (54.6%) reported 0 min of weekly physical activity. This was especially true of older female respondents. Performance expectation scores were lower among respondents who were in the oldest age-group, namely, white women. Physical activity knowledge varied by age-group, and barriers to physical activity were prevalent in all groups. The following are significant correlates of reported weekly physical activity: younger age, more education, fewer motivational barriers, and greater perceived health and performance expectations. CONCLUSIONS: Given the importance of physical activity to diabetes management, the low prevalence of physical activity found in this and other studies should raise concerns among clinicians. Future research to identify predictors of physical activity is needed to guide clinicians in the promotion of physical activity.

Physician and Sportsmedicine - vol 4 - no. 27 - april 1999 [Texto completo]

Exercise in Diabetes Management: Maximizing Benefits, Controlling Risks

Russell D. White, MD, with Carl Sherman

Series Editor: Nicholas A. DiNubile, MD

Am J Epidemiol 1999 Feb 1;149(3):219-27
Physical activity in elderly subjects with impaired glucose tolerance and newly diagnosed diabetes mellitus.
Baan CA, Stolk RP, Grobbee DE, Witteman JC, Feskens EJ
Department of Public Health, Erasmus University Rotterdam, The Netherlands.
The authors carried out a study to investigate the association between different indicators of physical activity and the prevalence of impaired glucose tolerance (IGT) and newly diagnosed diabetes (nDM) in a population-based cohort of elderly men and women in the Netherlands. A sample of participants of the Rotterdam Study (n = 1,016) aged 55-75 years who were not known to have diabetes mellitus underwent an oral glucose tolerance test. Physical activity was assessed by means of a self-administered questionnaire and expressed as time spent on activities per week. Associations with the prevalence of IGT and nDM were assessed by logistic regression analysis after adjustment for age, body mass index, waist-hip ratio, family history of diabetes, and smoking. A total of 745 subjects had normal glucose tolerance, 153 IGT, and 118 nDM. The total amount of time spent on physical activity decreased with increasing glucose intolerance. Adjusted for main confounders, vigorous activities such as bicycling (men: odds ratio (OR) = 0.26, 95% confidence interval (CI) 0.14-0.49; women: OR = 0.37, 95% CI 0.18-0.78) and sports (men: OR = 0.28, 95% CI 0.11-0.74) showed an inverse association with the presence of nDM. For IGT, the associations pointed in the same direction but did not reach statistical significance. These results indicate that physical inactivity and glucose intolerance are associated among older adults similar to the way they are associated among middle-aged adults.

Diabetes Metab 1998 Jun;24(3):281-90
[Physical activity and diabetes].
Gautier JF, Berne C, Grimm JJ, Lobel B, Coliche V, Mollet E
Service de Diabetologie, Hopital Saint-Louis, Paris, France.

An Med Interna 1998 Jun;15(6):294-7
[Usual physical activity level, glycemic control, and cardiovascular risk factors profile. Spanish Diabetes Society Working Group for the study of Nutrition].
OBJECTIVES: To know the relation between the usual physical activity pattern and metabolic control and cardiovascular risk factors of people with diabetes mellitus. RESEARCH DESIGN AND METHODS: 144 type 1 (insulin dependent) diabetic subjects (M/F, 70/74) and 193 type 2 (non insulin dependent) diabetic patients 8M/F, 81/112) fron DNCT study (Diabetes Nutrition and Complications Trial) were included in the study from May 1993 to December 1994. Physical activity index was assessed by means of the weekly caloric expenditure based upon previously published questionnaire. RESULTS: At least 60% of diabetic patients had a regular exercise more than 3 times per week. Unexpected, level of HbA1c, but not other parameters, was related to the level of physical activity, in that the higher the activity the higher HbA1c level in both type 1 and type 2 diabetic patients. CONCLUSIONS: In the DNCT study the higher physical activity level was associated a worsening in the HbA1c level. These un expected date there are take into account when recommending physical activity to people with diabetes mellitus with no good metabolic control.
Comments:
Comment in: An Med Interna 1998 Jun;15(6):291-3

An Med Interna 1998 Jun;15(6):291-3
[Physical activity and diabetes mellitus].
Calle Pascual AL
Publication Types:
Comment
Editorial
Comments:
Comment on: An Med Interna 1998 Jun;15(6):294-7

Diabetes Care 1998 Apr;21(4):555-62
Physical activity and NIDDM in African-Americans. The Pitt County Study.
James SA, Jamjoum L, Raghunathan TE, Strogatz DS, Furth ED, Khazanie PG
Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor 48109, USA. sjames@umich.edu
OBJECTIVE: Studies directly examining the association between physical activity and NIDDM in African-Americans are rare. Consequently, the strength of this association in this ethnic minority group remains unclear. The current study broadly characterizes the types of physical activity engaged in by a community sample of working-class African-Americans and then quantifies the association between physical activity and NIDDM risk in this population. RESEARCH DESIGN AND METHODS: During the 1993 reexamination of participants in the Pitt County Study in North Carolina, data on NIDDM history, current use of insulin or oral hypoglycemic drugs, and approximately 12-h overnight fasting blood glucose (FBG) were obtained from 598 women and 318 men, ages 30-55 years. The presence of NIDDM was determined by current insulin or medication use and FBG > or = 140 mg/dl. Study participants were assigned to one of four categories of physical activity: strenuous, moderate, low, or inactive. RESULTS: The weighted prevalence of NIDDM in the sample was 7.1%. After adjustment was made for age, sex, education, BMI, and waist-to-hip ratio, NIDDM risk for moderately active subjects was one-third that for the physically inactive subjects (odds ratio [OR], 0.35; 95% CI, 0.12-0.98). The ORs for low (OR, 0.51; 95% CI, 0.20-1.29) and strenuous (OR, 0.65; 95% CI, 0.26-1.63) activity also tended to be lower. A summary OR that contrasted any activity versus no activity was 0.51 (95% CI, 0.23-1.13). CONCLUSIONS: Moderate physical activity was strongly associated with reduced risk for NIDDM in this sample. While replication of these findings is needed, public health interventions designed to increase moderate (leisure-time) physical activity in black adults should be strongly encouraged.

JAMA 1998 Mar 4;279(9):669-74
Intensity and amount of physical activity in relation to insulin sensitivity: the Insulin Resistance Atherosclerosis Study.
Mayer-Davis EJ, D'Agostino R Jr, Karter AJ, Haffner SM, Rewers MJ, Saad M, Bergman RN
Department of Epidemiology and Biostatistics, School of Public Health, University of South Carolina, Columbia 29208, USA. ejmayerd@sph.sc.edu
CONTEXT: Exercise training is associated with improved insulin sensitivity (SI), but the potential impact of habitual, nonvigorous activity is uncertain. OBJECTIVE: To determine whether habitual, nonvigorous physical activity, as well as vigorous and overall activity, is associated with better SI. DESIGN: A multicultural epidemiologic study. SETTING: The Insulin Resistance Atherosclerosis Study, conducted in Oakland, Calif; Los Angeles, Calif; the San Luis Valley, Colo; and San Antonio, Tex. PARTICIPANTS: A total of 1467 men and women of African American, Hispanic, and non-Hispanic white ethnicity, aged 40 to 69 years, with glucose tolerance ranging from normal to mild non-insulin-dependent diabetes mellitus. MAIN OUTCOME MEASURE: Insulin sensitivity as measured by an intravenous glucose tolerance test. RESULTS: The mean SI for individuals who participated in vigorous activity 5 or more times per week was 1.59 min(-1) x microU(-1) x mL(-1) x 10(-4) (95% confidence interval [CI], 1.39-1.79) compared with 0.90 (95% CI, 0.83-0.97) for those who rarely or never participated in vigorous activity, after adjusting for potential confounders (P<.001). When habitual physical activity (estimated energy expenditure [EEE]) was assessed by 1-year recall of activities, the correlation coefficient between SI and total EEE was 0.14 (P<.001). After adjustment for confounders, vigorous and nonvigorous levels of EEE (metabolic equivalent levels > or = 6.0 and <6.0, respectively) were each positively and independently associated with SI (P< or =.01 for each). The association was attenuated after adjustment for the potential mediators, body mass index (a measure of weight in kilograms divided by the square of the height in meters), and waist-to-hip ratio. Results were similar for subgroups of sex, ethnicity, and diabetes. CONCLUSIONS: Increased participation in nonvigorous as well as overall and vigorous physical activity was associated with significantly higher SI. These findings lend further support to current public health recommendations for increased moderate-intensity physical activity on most days.

Diabetes Care 1997 Oct;20(10):1603-11
Impact of physical activity on cardiovascular risk factors in IDDM.
Lehmann R, Kaplan V, Bingisser R, Bloch KE, Spinas GA
Division of Endocrinology and Diabetes, University Hospital Zurich, Switzerland.
OBJECTIVE: To study the impact of physical activity on glycemic control and plasma lipids [HDL cholesterol (HDL-C), HDL-C subfractions, triglycerides, lipoprotein(a)], blood pressure, weight, and abdominal fat and to determine the necessary short-term adaptations in diabetes management during intensive endurance training in patients with IDDM. RESEARCH DESIGN AND METHODS: Well-controlled subjects with IDDM (n = 20; HbA1c = 7.6%) engaged in a regular exercise program over a period of 3 months involving endurance sports such as biking, long-distance running, or hiking. Subjects were instructed to exercise at least 135 min per week. If baseline activity exceeded this level, subjects were to increase further their physical activity as much as possible and record the type and time of such activity. RESULTS: During the 3-month intervention, physical activity increased from 195 +/- 176 to 356 +/- 164 min (mean +/- SD) per week (P < 0.001). Physical fitness as assessed by VO2max increased from 2,914 +/- 924 to 3,092 +/- 905 ml/min (P < 0.001), and insulin sensitivity increased significantly (steady-state plasma glucose [SSPG] decreased from 10.5 +/- 4.8 to 7.0 +/- 3.3 mmol/l; P < 0.01). Subsequently, LDL cholesterol decreased by 14% (P < 0.05), and HDL and HDL3-C subfraction increased by 10 (P < 0.05) and 16% (P < 0.05), respectively. Systolic and diastolic blood pressure decreased significantly from 127 +/- 9 to 124 +/- 8 (P < 0.05) and from 80 +/- 5 to 77 +/- 5 mmHg (P < 0.01), respectively. Resting heart rate decreased from 63 +/- 6 to 59 +/- 7 bpm (P < 0.01). Waist-to-hip circumference ratio decreased from 0.882 +/- 0.055 to 0.858 +/- 0.053 (P < 0.001), body weight decreased from 70.7 +/- 10.4 to 68.7 +/- 10.2 kg (P = 0.003), with a consequent decrease in body fat from 21.9 +/- 8.2 to 18.0 +/- 6.3% (P < 0.001) and an increase in lean body mass from 54.9 +/- 12.2 to 56.8 +/- 11.0 kg. These effects occurred independently of glycemic control. The overall frequency of severe hypoglycemic episodes was reduced from 0.14 to 0.10 per patient-year during the study period. CONCLUSIONS: This study shows that increasing physical activity is safe and does not result in more hypoglycemic episodes and that there is a linear dose-response between increased physical activity and loss of abdominal fat and a decrease in blood pressure and lipid-related cardiovascular risk factors, with a preferential increase in the HDL3-C subfraction.
Publication Types:
Clinical trial

Diabetes Care 1996 Oct;19(10):1118-21
Relationship of locus of control to physical activity among people with and without diabetes.
Gregg EW, Kriska AM, Narayan KM, Knowler WC
Department of Epidemiology, University of Pittsburgh, Pennsylvania, USA. egregg@moose.uvm.edu
OBJECTIVE: To examine the relationship between locus of control (LOC) (internal and external) and physical activity in Pima Indians and to determine whether this relationship is affected by the presence of diabetes. RESEARCH DESIGN AND METHODS: A population-based sample of 580 Pima Indians was recruited from an ongoing research study. LOC was measured on a 1-40 modified Rotter scale, and past year total physical activity (leisure and work physical activity levels combined) was measured by interviewer-administered questionnaire. RESULTS: Among both men and women without diabetes, individuals with an internal LOC (score 1-16) were significantly (P < 0.01) more active than those with an external (score 17-40) LOC (70 vs. 30 median metabolic equivalent [MET] hours per week for men: 12 vs. 5 median MET hours per week for women). Controlled for age and BMI, an internal LOC was significantly associated with a higher level of physical activity among men (P = 0.04) and women (P = 0.001) without diabetes, but not among those with diabetes. CONCLUSIONS: Nondiabetic Pima Indians with an internal LOC are more physically active than those with an external LOC. Enhancing perceptions of internal control may influence physical activity and thus have implications for diabetes prevention.

Am J Epidemiol 1995 Feb 15;141(4):360-8
Physical activity and incidence of diabetes: the Honolulu Heart Program.
Burchfiel CM, Sharp DS, Curb JD, Rodriguez BL, Hwang LJ, Marcus EB, Yano K Honolulu Epidemiology Research Section, National Heart, Lung and Blood Institute, Honolulu, HI.
Few prospective studies have assessed the relation between physical activity and diabetes. The authors examined this relation prospectively among 6,815 Japanese-American men in the Honolulu Heart Program who were aged 45-68 years and initially free of diagnosed diabetes in 1965-1968. A physical activity index was calculated based on time spent per day in different activity levels and a weighting factor correlated with estimated oxygen consumption. Incidence of clinically recognized diabetes was based on self-reported use of diabetic medication at one of two subsequent examinations. The age-adjusted 6-year
cumulative incidence of diabetes decreased progressively with increasing quintile of physical activity from 73.8 to 34.3 per 1,000 (p < 0.0001, trend) in all men and from 53.9 to 21.7 per 1,000 (p < 0.0001, trend) among men with a non-fasting glucose level < 225 mg/dl one hour after a 50-gm load, the latter group being less likely to have unrecognized diabetes at baseline. When stratified by tertile of baseline glucose, trends in incidence across physical activity quintiles were statistically significant in the low and middle tertiles but not in the high tertile. Similar inverse trends were observed for men in the lower four quintiles of body mass index, however, these trends were weaker and not significant for men in the upper quintile of body mass index. Age-adjusted odds ratios for diabetes comparing the upper with the lower four quintiles of physical activity were 0.55 (95% confidence interval (CI) 0.41-0.75) for all men and 0.50 (95% CI 0.33-0.74) for men with glucose < 225 mg/dl. After adjustment for age, body mass index, subscapular/triceps skinfold ratio, systolic blood pressure, triglycerides, glucose, hematocrit, and parental history of diabetes, odds ratios were still statistically significant and similar in magnitude. Restriction of analyses to men who remained free of cardiovascular disease during the study period produced similar results, which suggests that inactivity due to subclinical cardiovascular disease is unlikely to be responsible for these findings. Risk factor-adjusted odds ratios for older men (55-68 years) demonstrated that physical activity confers at least the same degree of protection as in younger men (45-54 years). These results indicate that physical activity is associated inversely with incident diabetes and that the beneficial effect does not appear to be mediated through improvements in other risk factors assessed in this study.