Obesity represents a growing public health concern, affecting more than 15% of the global adult population and involving a multi-billion market that comprises nutritional, surgical, psychological, and multidisciplinary interventions. The objective of this retrospective study was to evaluate the short-term efficacy and body weight measurements associated with differing levels of physical activity following the use of Allurion’s ingestible gastric balloon that was designed to increase feelings of fullness and decrease food consumption, being naturally eliminated after approximately 16 weeks. This study involved 571 individuals who qualified for the intervention for being older than 20 years with a body mass index (BMI) of 27 kg/m2 or more. Utilizing the Scale App Health Tracker and Allurion’s smartwatch, this study was able to track vital signs and physical activity in real time. The participants had an average initial BMI of 34.1 kg/m2 and a median age of 41 years. Notable outcomes were observed in both study groups, “Less Active” and “More Active”, which were classified by achieving less or more than a median number of 8000 daily steps. Specifically, body fat percentage saw a reduction from 33.1 ± 9.4 to 28.3 ± 10.2 in the less active group and from 32.2 to 27.5 in the more active group, with both groups achieving statistical significance (p < 0.001). Additionally, there was a significant reduction in average weight, dropping from 98.2 ± 22.8 kg to 84.6 ± 19.3 kg in the less active group and from 97.7 ± 21.0 kg to 82.1 ± 22.9 kg in the more active group (both p < 0.001). Interestingly, those in the more active group also experienced a significant increase in lean mass compared to their less active counterparts (p = 0.045), although no substantial differences in weight loss, BMI reduction, and total body fat decrease were observed between the two groups. This investigation confirms the hypothesis that Allurion’s ingestible gastric balloon significantly reduces weight in the short term and enhances several physical health metrics, demonstrating effectiveness as an autonomous method for challenging weight management, regardless of the level of daily physical activity.