i find step ups better than lunges (but i hate lunges with a passion) 2 things. first, do you squat?.... if not than squat instead of either one. 2nd how high is your step up?....... i know this will sound crazy...... but if you want to get the most out of step ups, have your step about 6 inches of the platform up to a foot. you can use a lot of weight and everything hurts real bad.
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