Physical activity a risk is a protective factor against dietary lapses after weight loss.
Nearly everyone who is trying to lose weight and gained the weight back dreads relapse on their next try. The fact is that very few people avoid weight regain that comes after weight loss. Dietary lapses drive weight loss and maintenance failures. Specific factors often influence the risk of lapse, and physical activity may be one such risk factor.
Even though physical activity may increase or decrease appetite, many experts continue to suggest exercise as a means to prevent weight regain and assist with weight loss. The problem is that most research shows that the effect of exercise on weight loss is modest at best. The effect on the risk of lapses is unclear and limited research has been on this area.
A new study was done in 2020 to look at exercise and lapses in the diet  . This new study aimed to maximize validity by examining the extent to which physical effects dietary lapses among dieters. In the study, 130 overweight participants were 130 adults were enrolled. Dieters were not just placed on a lower calorie diet and weight loss treatment instructed to follow a physical activity and dietary prescription.
At mid-treatment, moderate-to-vigorous physical activity and light physical activity were measured using hip-worn accelerometers. Lapses were assessed. Within-subject total physical activity and light physical activity negatively predicted lapse. The moderate-to-vigorous physical activity followed the same pattern, but the effect was not statistically significant.
The bottom line: Exercise is helpful at predicting the prevention of weight loss lapse. This study was the first to investigate if objectively measured physical activity prospectively. It appears that a lack of exercise predicts lapse from a weight loss program. Results suggested that for every additional 10 min of total PA one engaged in, the risk of lapse decreased by 1%. I would recommend adding physical activity to your weight loss and maintenance plans.