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Abstract

Background

Because lifestyle-induced improvements in cardiovascular risk factors vary substantially across individuals with type 2 diabetes, we investigated the extent to which increases in fitness explain cardiovascular risk factor improvements independent of weight loss in a lifestyle intervention.

Methods

We studied 1-year changes in Look AHEAD, a randomized trial comparing an intensive lifestyle intervention (ILI) to a diabetes support and education (DSE) control group in adults with type 2 diabetes. Assessments included weight, fitness, blood pressure (BP), glucose, HbA1c, and lipids. We evaluated the effects of changes in weight and fitness on changes in cardiovascular risk factors by study arm, using R² from multiple linear regression.

Results

Analyses included participants with fitness data at baseline and 1-year (n = 4408; 41% male, 36% non-white; mean age 58.7 ± 6.8 years). Weight change alone improved R² for explaining changes in risk factors up to 8.2% in ILI and 1.7% in DSE. Fitness change alone improved R² up to 3.9% in ILI and 0.8% in DSE. After adjusting for weight change, fitness was independently associated (p < 0.05) with improvements in R² for glucose (+0.7%), HbA1c (+1.1%), high-density lipoprotein (HDL) cholesterol (+0.4%), and triglycerides (+0.2%) in ILI and diastolic BP (+0.3%), glucose (+0.3%), HbA1c (+0.4%), and triglycerides (+0.1%) in DSE. Taken together, weight and fitness changes explained from 0.1–9.3% of the variability in cardiovascular risk factor changes.

Conclusion

Increased fitness explained statistically significant but small improvements in several cardiovascular risk factors beyond weight loss. Further research identifying other factors that explain cardiovascular risk factor change is needed.

Keywords

Cardiovascular risk factor fitness lifestyle intervention obesity

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References

Vidal

. Updated review on the benefits of weight loss. Int J Obes Relat Metab Disord 2002; 26(Suppl 4): S25–S28.

Pi-Sunyer

Blackburn

Brancati

. Reduction in weight and cardiovascular disease risk factors in individuals with type 2 diabetes: one-year results of the look AHEAD trial. Diabetes Care 2007; 30(6): 1374–1383.

Warburton

Nicol

Bredin

. Health benefits of physical activity: the evidence. CMAJ 2006; 174(6): 801–809.

Balducci

Zanuso

Nicolucci

. Anti-inflammatory effect of exercise training in subjects with type 2 diabetes and the metabolic syndrome is dependent on exercise modalities and independent of weight loss. Nutr Metab Cardiovasc Dis 2010; 20(8): 608–617.

Ryan

Espeland

Foster

. Look AHEAD (Action for Health in Diabetes): design and methods for a clinical trial of weight loss for the prevention of cardiovascular disease in type 2 diabetes. Control Clin Trials 2003; 24(5): 610–628.

Borg

. Perceived exertion. Exerc Sport Sci Rev 1974; 2: 131–153.

Wadden

West

Delahanty

. The Look AHEAD study: a description of the lifestyle intervention and the evidence supporting it. Obesity (Silver Spring) 2006; 14(5): 737–752.

Friedewald

Levy

Fredrickson

. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem 1972; 18(6): 499–502.

American College of Sports Medicine, Thompson WR, Gordon NF and Pescatello LS. ACSM's guidelines for exercise testing and prescription, 8th edn. Philadelphia: Lippincott Williams and Wilkins, 2010.

10.

Jakicic

Jaramillo

Balasubramanyam

. Effect of a lifestyle intervention on change in cardiorespiratory fitness in adults with type 2 diabetes: results from the Look AHEAD Study. Int J Obes (Lond) 2009; 33(3): 305–316.

11.

Thomas

Elliott

Naughton

. Exercise for type 2 diabetes mellitus. Cochrane Database Syst Rev 2006; (3): CD002968–CD002968.

12.

Donnelly

Blair

Jakicic

. American College of Sports Medicine Position Stand. Appropriate physical activity intervention strategies for weight loss and prevention of weight regain for adults. Med Sci Sports Exerc 2009; 41(2): 459–471.

13.

Boule

Haddad

Kenny

. Effects of exercise on glycemic control and body mass in type 2 diabetes mellitus: a meta-analysis of controlled clinical trials. JAMA 2001; 286(10): 1218–1227.

14.

Boule

Kenny

Haddad

. Meta-analysis of the effect of structured exercise training on cardiorespiratory fitness in Type 2 diabetes mellitus. Diabetologia 2003; 46(8): 1071–1081.

15.

Colberg

Grieco

. Exercise in the treatment and prevention of diabetes. Curr Sports Med Rep 2009; 8(4): 169–1675.

16.

Kelley

. Effects of aerobic exercise on lipids and lipoproteins in adults with type 2 diabetes: a meta-analysis of randomized-controlled trials. Public Health 2007; 121(9): 643–655.

17.

Durstine

Grandjean

Davis

. Blood lipid and lipoprotein adaptations to exercise: a quantitative analysis. Sports Med 2001; 31(15): 1033–1062.

18.

Durstine

Grandjean

Cox

. Lipids, lipoproteins, and exercise. J Cardiopulm Rehabil 2002; 22(6): 385–398.

19.

Pescatello

Franklin

Fagard

. American College of Sports Medicine position stand. Exercise and hypertension. Med Sci Sports Exerc 2004; 36(3): 533–553.

20.

Balducci

Zanuso

Nicolucci

. 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(20): 1794–1803.

21.

Zanuso

Jimenez

Pugliese

. Exercise for the management of type 2 diabetes: a review of the evidence. Acta Diabetol 2010; 47(1): 15–22.

22.

Estruch

Martinez-Gonzalez

Corella

. Effects of a Mediterranean-style diet on cardiovascular risk factors: a randomized trial. Ann Intern Med 2006; 145(1): 1–11.

23.

Abete

Goyenechea

Zulet

. Obesity and metabolic syndrome: potential benefit from specific nutritional components. Nutr Metab Cardiovasc Dis 2011; 21(Suppl 2): B1–B15.

24.

Taylor

Conrad

Wilhelm

. Does improving mood in depressed patients alter factors that may affect cardiovascular disease risk? J Psychiatr Res 2009; 43(16): 1246–1252.

25.

Blumenthal

Sherwood

Babyak

. Effects of exercise and stress management training on markers of cardiovascular risk in patients with ischemic heart disease: a randomized controlled trial. JAMA 2005; 293(13): 1626–1634.

26.

Ordovas

Shen

. Gene-environment interactions and susceptibility to metabolic syndrome and other chronic diseases. J Periodontol 2008; 79(8 Suppl): 1508–1513.

27.

Lekakis

Abraham

Balbarini

. Methods for evaluating endothelial function: a position statement from the European Society of Cardiology Working Group on Peripheral Circulation. Eur J Cardiovasc Prev Rehabil 2011; 18(6): 775–789.

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Effect of improved fitness beyond weight loss on cardiovascular risk factors in individuals with type 2 diabetes in the Look AHEAD study

Abstract

Background

Methods

Results

Conclusion

Keywords

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References

Supplementary Material