THE INDEPENDENT AND COMBINED EFFECTS OF AEROBIC EXERCISE AND DIETARY FISH INTAKE ON SERUM-LIPIDS AND GLYCEMIC CONTROL NIDDM - A RANDOMIZED CONTROLLED-STUDY

OBJECTIVE - The triglyceride-lowering effects of omega-3 fats and HDL cholesterol-raising effects of exercise may be appropriate management for dyslipidemia in NIDDM. However, fish oil may impair glycemic contr ol in NIDDM. The present study examined the effects of moderate aerobi c exercise and the incorporation of fish into a low-fat (30% total ene rgy) diet on serum lipids and glycemic control in dyslipidemic NIDDM p atients. RESEARCH DESIGN AND METHODS - In a controlled, 8-week interve ntion, 55 sedentary NIDDM subjects with serum triglycerides >1.8 mmol/ l and/or HDL cholesterol <1.0 mmol/l were randomly assigned to a low-f at diet (30% daily energy intake) with or without one fish meal daily (3.6 g omega-3/day) and further randomized to a moderate (55-65% VO2ma x) or light (heart rate <100 bpm) exercise program. An oral glucose to lerance test (75 g), fasting serum glucose, insulin, lipids, and GHb w ere measured before and after intervention. Self-monitoring of blood g lucose was performed throughout. RESULTS - In the 49 subjects who comp leted the study, moderate exercise improved aerobic fitness (VO2max) b y 12% (from 1.87 to 2.07 l/min, P = 0.0001). Fish consumption reduced triglycerides (0.80 mmol/l, P = 0.03) and HDL3 cholesterol (0.05 mmol/ l, P = 0.02) and increased HDL2 cholesterol (0.06 mmol/l, P = 0.01). A fter adjustment for age, sex, and changes in body weight, fish diets w ere associated with increases in GHb (0.50%, P = 0.05) and self-monito red glucose (0.57 mmol/l, P = 0.0002), which were prevented by moderat e exercise. CONCLUSIONS - A reduced fat diet incorporating one daily f ish meal reduces serum triglycerides and increases HDL2 cholesterol in dyslipidemic NIDDM patients. Associated deterioration in glycemic con trol can be prevented by a concomitant program of moderate exercise.