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Beginning (gram on the left) – Standing with your feet together, step one leg back to a lunge then back together. Keep repeating while alternating legs.

Intermediate (mom in the middle) – Starting with your feet together, jump out to a lunge, then back to standing with your feet together. Keep repeating while alternating legs.

Advanced (me on the right) – Continuous hopping/jumping lunges, keep repeating and alternating legs.