Are you losing Body Fat or Muscle?
Issues that people come across when wanting to lose body fat is they want to lose body fat quickly in the shortest time possible but what happens when your body will only let you burn under 1% body fat per week? What is the other weight you seem to be burning? Among the body fat you burn away there will be muscle and water loss at the same time. How much though will be determined by what and how much you eat.
An example of what to do without sacrificing your hard earned muscle is as follows:
It is known that the deficit of energy needed to maximise fat loss without sacrificing muscle is a 500 calorie deficit of your current BMR. With keeping to this and having an effective training program your on your way to burning that unwanted body fat and not sacrificing your muscle in the process. Actually you will able to gain muscle and speed up your metabolic rate.
Increase this deficit to 1000 calories and yes you will be losing weight but you will compromise some muscle at the same time. Within 5 weeks you could be burning a rate of approx. 200gm of muscle.
The bottom line is to be smart with your training and nutrition. Eat according to what you need and how much muscle you have whilst keeping your training load challenging and heavy with great form of course.
Aim for just under 1% of body fat loss per week
Using endurance based exercises to lose body fat and burn more calories will lead to a catabolic state (muscle waste)
Keep your training heavier with very strict form
With your nutrition your first importance will be protein when aiming for optimal body composition and losing body fat. Try not to have less than 1.5gm of protein per kg of bodyweight to preserve muscle
Keep up your cardio training but do not rely on it as your main way of losing body fat.