Weight Loss: No Results from Exercise

Question:

I have been training a client for 16 weeks now and her results have been slow. She does four cardio sessions per week (interval training) for 60 minutes per session and weight trains twice per week for 60 minutes at a moderate to high intensity. She is currently participating in Weight Watchers, although she doesn’t always eat enough and binge drinks once a week (six glasses of wine). Although she hasn’t lost any weight, her girth measurements and body fat have lowered marginally. Her shape has changed, and her fitness level has increased greatly.

My question is, why hasn’t she lost weight, and why haven’t her body fat and measurements altered significantly when her fitness levels have increased?

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