The goal of this study was to evaluate a program of resistance weight training on cardiovascular risk factors, blood glucose management, and overall strength in diabetic subjects. A randomized crossover design was performed on eight male type I (insulin-dependent) diabetic subjects (mean +/- SD age 31 +/- 3.5 yr, height 176 +/- 5.6 cm, body wt 80 +/- 15 kg, duration of diabetes 12.3 +/- 9.8 yr, and insulin dose 24 U NPH/day and 21 U regular/day). The program consisted of heavy-resistance weight training 3 days/wk for 10 wk, concentrating on the strengthening of major muscle groups through progressive resistance. Blood tests included total cholesterol, triglycerides, very-low-density lipoprotein and high-density lipoprotein cholesterol, and HbA1c. These tests were repeated at three time points during the program. Field-strength testing was performed before and after training. An improvement was seen in the squat (93.6% increase, P less than 0.0001) and bench press (58% increase, P less than 0.005). HbA1c and triglyceride levels showed no change during the resting portion of the experiment but showed a significant change with the training program: HbA1c 6.9 +/- 1.4 vs 5.8 +/- 0.9% (P = 0.05) and triglyceride 5.044 +/- 1.06 vs. 4.628 +/- 0.88 mM (P = 0.01). Self-monitored glucose (taken pre- and postexercise) showed a decrease from 7.85 +/- 3.13 to 7.05 +/- 2.91 mM (P = 0.0001). Very-low-density lipoprotein cholesterol and triglycerides did not change after training. Analysis of variance showed no significant differences over time from the three time points with regard to reductions in cardiovascular risk factors or HbA1c.(ABSTRACT TRUNCATED AT 250 WORDS)