MORE REPS OF SQUATS= SLIM?!?

My wife does 30 minutes at 50 steps per minute on the stair master she has lost 1/2 an inch on her thighs (from 21 to 20 1/2) and 1/4 inch on her calves (from 14 to 13 3/4) and lost 5 pounds, in 1 year. The previous year she lost 80 pounds.