Department of Internal Medicine, Section of Internal Medicine, Endocrine and Metabolic Sciences, University of Perugia, Via E. Dal Pozzo, 06126 Perugia, Italy.
OBJECTIVE: To establish the impact of different amounts of increased energy expenditure on type 2 diabetes care. RESEARCH DESIGN AND METHODS: Post hoc analysis of long-term effects of different amounts of increased energy expenditure (metabolic equivalents [METS] per hour per week) through voluntary aerobic physical activity was performed in 179 type 2 diabetic subjects (age 62 +/- 1 years [mean +/- SE]) randomized to a physical activity counseling intervention. Subjects were followed for 2 years and divided into six groups based on their increments in METs per hour per week: group 0 (no activity, n = 28), group 1-10 (6.8 +/- 0.3, n = 27), group 11-20 (17.1 +/- 0.4, n = 31), group 21-30 (27.0 +/- 0.5, n = 27), group 31-40 (37.5 +/- 0.5, n = 32), and group >40 (58.3 +/- 1.8, n = 34). RESULTS: At baseline, the six groups did not differ for energy expenditure, age, sex, diabetes duration, and all parameters measured. After 2 years, in group 0 and in group 1-10, no parameter changed; in groups 11-20, 21-30, 31-40, and >40, HbA(1c), blood pressure, total serum cholesterol, triglycerides, and estimated percent of 10-year coronary heart disease risk improved (P < 0.05). In group 21-30, 31-40, and >40, body weight, waist circumference, heart rate, fasting plasma glucose, serum LDL and HDL cholesterol also improved (P < 0.05). METs per hour per week correlated positively with changes of HDL cholesterol and negatively with those of other parameters (P < 0.001). After 2 years, per capita yearly costs of medications increased (P = 0.008) by USD393 in group 0, did not significantly change in group 1-10 (USD 206, P = 0.09), and decreased in group 11-20 (USD -196, P = 0.01), group 21-30 (USD -593, P = 0.009), group 31-40 (USD -660, P = 0.003), and group >40 (USD -579, P = 0.001). CONCLUSIONS: Energy expenditure >10 METs . h(-1) . week(-1) obtained through aerobic leisure time physical activity is sufficient to achieve health and financial advantages, but full benefits are achieved with energy expenditure >20 METs . h(-1) . week(-1).