The purpose of this study was to determine the effect wearing a weight lifting belt (WLB) has on heart rate and blood pressure during aerobic bicycle ergometer, one-arm bench press, and isometric dead lift exercise. Open circuit spirometry was used to determine bicycle ergometer peak VO2during a progressive bicycle ergometer test. One armed one repetition maximum (1 RM) bench press and maximal isometric dead lift were determined. Blood pressure (BP) was determined by auscultation. Six healthy subjects performed three types of exercise twice, once with a WLB and once without. After warmup, subjects either bicycled at 60 percent of peak VO2for six minutes, performed three sets of 10 repetition bench presses with 60 percent 1 RM, or held an isometric dead lift for two minutes with 40 percent of maximal isometric dead lift. Assignment of WLB or no WLB exercise was random. Heart rate (HR), BP, and WLB pressure on the abdominal wall was monitored continuously both during exercise and during recovery. A two way (beltino belt and time) repeated measures factorial design was used to analyze the date (α=.05). WLB pressure on abdominal wall (measured using a rubber bladder) increased across exercise time in the bench press and back lift. After an initial significant increase in pressure during the first two minutes of the aerobic exercise, WLB pressure stabilized and remained steady throughout the exercise. Mean systolic BP was significantly higher with WLB use for the aerobic and isometric activities. A significant HR increase with WLB use was found for the aerobic exercise. Also with WLB use rate pressure product was significantly higher for all types of exercise (6 to 15 percent). It is felt that the use of a WLB can put an added strain on the cardiovascular system. Individuals that may have a compromised cardiovascular system are probably at greater risk when undertaking exercise with back support. © 1989 Journal of Applied Sport Science Research. All right reserveds.