Exercise has been shown to offer numerous health benefits and be particularly important in preventing weight gain or regain for people with obesity. Exercise guidelines can be difficult to interpret and apply independently and do not address specific exercise limitations in individuals with obesity. The exercise monitoring system proposed in this study might provide a new method to meet aerobic exercise guidelines independently with reduced risk of injury.

The exercise monitoring system controls, in real-time, the intensity of an exercise session consisting of treadmill walking. During treadmill walking, the exercise monitoring system will instruct participants to increase or decrease how much participants raise their knees and swing their arms while maintaining a smooth contact with the ground, based on real-time readings of the participants' heart rate.

In this clinical trial, each participant will perform a control and an experimental training session. Both training sessions will include four blocks of 7 minutes of treadmill walking alternated with three periods of rest (3 min). In the control session, participants will monitor the intensity of exercise independently using a standard heart rate monitor and control it by adjusting their walking speed. In the experimental session, each participant will follow the exercise monitoring system instructions displayed on a TV, and treadmill walking speed will be set at a comfortable walking speed. Target heart rates of 60% HRR will be used as the exercise intensities in both training sessions. The investigators will examine energy expenditure, heart rate, and kinematic measures under control and experimental conditions. The goals of this clinical trial are to determine the effect of exercising with the exercise monitoring system in individuals with obesity. The investigators hypothesized that the experimental session will result in higher total energy cost and efficiency than the control session; and in lower heart rate error, tibial positive peak accelerations and feedback errors than the control session.

The results of this study will inform proposals for larger interventions that will focus on 1) testing different types of obesity and osteoarthritis, 2) adding a resistance-training component, and 3) integrating a diet intervention.

Inclusion Criteria:

• BMI ≥ 30.0 kg/m2 and ≤ 40.0 kg/m2
• Age 20 to 45 years;
• Able to understand spoken English at the level needed to:
• understand and follow instructions for equipment setup, testing, and task performance
• answer questions related to effort and preference
• be able to understand consent document and provide informed assent

Exclusion Criteria:

• Any signs or symptoms suggestive of cardiovascular, pulmonary, metabolic, or renal disease.
• Any injury or health condition that affects the ability to walk on a treadmill.

4 months