As the other guys have said, it comes down to your diet. A simple idea of how a diet is important; If you eat small(ish) clean regular meals throughout the day (around 5/6) you will infact boost your metabolism naturally, this will make your body burn more calories.
If you are trying to lose body fat and also gain muscle, whilst dieting, keep doing your weight training. Again, same as a diet, you can get a decent workout plan too!
I would also add some cardio into your training.
A great way of burning the calories is 'Fasted Cardio', this is when you wake up, before breakfast, you go for a fast-paced walk. Not a dordle, nor a run. Just a fast walk where your heart rate has increased and you feel your body getting sticky. Do this for 40 mins, come back, have a protein shake and then your breakfast.
A little tip, with your breakfast, Porridge Oats is a good choice. It's a good clean carbohydrate, will provide sustained energy throughout the day and you can never put weight on with just oats.
For flavour, you could add a scoop of low carb/low calorie whey protein :)
Hope that basic information helps!
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