Sit on the front of a bench slightly in front of a power rack. Loop a band around each leg just below the knee that attaches to that side of the power rack so it pulls out and slightly back.
 
Keeping your feet slightly off the floor and the hip bent to about 90 degrees, bring the knees together and then return under control to the widest position you’re able to reach.
 
Purpose
The seated 90/90 band adduction strengthens transverse adduction, a position similar to a squat, to strengthen that function of the adductors.
 
Programming
Do 2-3 sets of 10-20 reps. Slow eccentrics are valuable during early rehab of a groin strain.