Being active boosts your daily calorie burn more than previously thought. Researchers found that increased physical activity raises total energy use without triggering the body to conserve energy ... Here is an image in which the area is marked in green: (NSFW, genitals covered).

Understanding the Context

Please note how the 'string' of the taut adductor muscles separates the groin on the front side of the trunk from the area in question on the trunk's underside. The image shows a female body and the perineum is invisible below the genitalia in the shadow between the buttocks. (Image source -NSFW, explicit)