It was stated that the atmospheric pressure and partial oxygen pressure are the most important climatic changes that have direct and indirect effects on human health. Regular aerobic exercise causes cardiovascular, neural, humoral, and metabolic changes. Many of these are likely to influence cardiovascular risk and the changes vary according to the level and duration of increased physical activity. The present study aims at identifying the relationship between changes in the climatic environment and the occurrence of some degenerative diseases [coronary heart disease and diabetes mellitus]. It also aims at improving the physiological condition of subjects with high risk of coronary heart disease or diabetes mellitus. This work was conducted for 12 weeks in the period from the first of October 1998 to the end of December 1998 in Queens hospital, medical research unit of New York University, Colombia University, and Virtecal Gym in New York. The study included 40 male subjects with coronary risk factors in the form of hypertension, smoking, hyperlipidemia, or family history of diabetes mellitus in the age group from 30 to 50 years. Two groups each of 20 subjects represented those with coronary risk factors and those with relative diabetes mellitus high risk. Ten persons from each of the subgroups were included, after their approval, in a physical exercise program especially designed for members with the corresponding risk for 3 sessions per week for 3 months. Multistage exercise stress test was carried out several times; the first one under usual temperature of the lab at sea level to assess the physical fitness for every person and it was repeated in the atmospheric pressure simulation control room at the end of each phase of the experiment to standardize the exercise loads of the suggested program. Exercise loads started at simulated 500 meters above the sea level which corresponds to 140 mm Hg partial oxygen pressure for 3 weeks. The level was increased by 500 meters every 3 weeks. No statistically significant differences were found between measures before and after the program in the two control groups. However, statistically significant differences were observed between measures before and after the program in the two experimental groups at 0.01 level. A statistically significant reduction was observed in body weight, serum cholesterol and triglycerides, resting and maximum heart rate, resting and maximum systolic blood pressure, double product, and heart rate after 2,4, and 6 minutes of recovery in both experimental groups as compared to the control groups. Again, a statistically significant reduction was demonstrated in blood sugar of the experimental group as compared to the control group of diabetes high risk. On the other hand, chronotropic reserve, exercise tolerance in minutes, as well as the exercise distance in miles were increased in both experimental groups as compared to the control groups.