Squats are utilised in a large range of exercise, rehabilitation and occupational settings, requiring engagement from trunk and lower limb muscles. In a recent study, we explored the engagement of deep muscles in the abdominal wall, particularly the transvere abdominis using imaging ultrasound to better understand their role during variations of squats. As a comparison, prone planks were performed given they largely target abdominal muscles during training. Overall, as expected, prone planks required greater engagement of external oblique but no difference was observed for internal oblique or transverse abdominis compared to double leg and single leg squats, safety bar and trap bar dead lifts. Therefore, when performing squats without specific instructions to engage abdominal muscles, no major difference is expected in relation to prone planks. However, external oblique was similarly engage to prone planks when performing single leg squats.