Although Tracy Anderson suggests you wear anke weights to enhance her workout of thighs and glutes, that is not necessary and in fact may negatively impact your mobility and health. Start slowly. Do one of the three workouts a day until your core becomes accustomed to the routine.
Do not use ankle weights if you are over 35. Love her cadence, sense of humor and think this is a great workout to tackle the core and hard to exercise parts of the body. She does a great job!
The exercises are effective however I like an instructor who guides you through the whole thing because the way Tracy teaches you have to twist yourself up to watch her change moves because she gives hardly any cues.