Objective: To investigate exercise intensity in healthy sedentary women using LBL and measure their substrate utilization during exercise. The former session was determined by measuring absolute [i.e., energy expenditure (EE)] and relative [i.e., percentage of rate of peak oxygen consumption (V̇O2 peak), maximal heart rate (HRmax ), rating of perceived exertion (RPE), and rating of perceived dyspnea (RPD)] indicators, whereas the latter was determined by measuring oxygen consumption and carbon dioxide production (V̇CO2).

Material and Method: Ten female subjects randomly performed two visits of exercise at least seven days apart. The first was a peak exercise test, and the second consisted of three 30-minute sessions of rest, exercise with LBL, and recovery. The V̇O2, V̇CO2, and EE were determined based on the expired air at the last five minutes of resting and exercise, whereas electrocardiograms were recorded to measure HR throughout the three sessions. Subjects were asked to provide RPE and RPD at the end of the exercise session.

Results: During exercise with LBL, average %V̇O2 peak and %HRmax were 43.5%±2.32% and 52.8%±1.81%, respectively, while EE, RPE, and RPD were 3.01±0.53 metabolic equivalents, 12.2±1.8, and 3.0±1.41, respectively. In addition, fat and especially CHO utilization were increased by the exercise.

Conclusion: These findings indicate that LBL offers a means of low-intensity exercise in healthy females while still providing physiological and metabolic benefits.

Keywords: Oxygen consumption, Heart rate, Energy expenditure, Exertion, Dyspnea, Women