The Oslo Diet and Exercise Study (ODES): design and objectives.

The Oslo Diet and Exercise Study (ODES) is an unmasked randomized 2 x 2 factorial trial of 1-year duration for each participant. During 1990-1991 219 participants (198 males and 21 females) aged 41-50 were randomized into one of four treatment groups; no treatment (control), dietary changes alone, exercise alone, or a combination of the two treatments. At inclusion, the participants had no overt heart disease, but they had increased body weight; slightly increased blood pressure, serum triglycerides, and total cholesterol, and they had decreased HDL cholesterol. Further, they were all inactive at leisure time. The primary aim of the trial is to compare the isolated and combined effects of the four treatments on the variables fibrinogen, fibrinolytic capacity, coagulation factor VII, and platelet volume. A series of secondary hypotheses will also be tested, such as the effects on other coagulation and fibrinolytic components and activities; lipids and lipoproteins; fatty acids; glucose and insulin response to a glucose load; clinical, physiological, and anthropometric variables; and quality of life. The dietary treatments are adapted according to each participant's risk profile (level of total cholesterol, HDL cholesterol, triglycerides, blood pressure, and body weight). Fish and fish products are recommended. Special emphasis is put on caloric restriction in those who are overweight and those with elevated blood pressure. Exercise sessions take place three times a week under the guidance of highly qualified instructors. The aim is to increase peak oxygen uptake through aerobic endurance training. Adherence to the exercise program is monitored closely.