When you are exercising regularly your muscles retain water (it takes 3 water molecules to bond to each glycogen molecule, and this helps deliver energy to the muscles more efficiently). So if you have stopped working out or reduced your workout schedule then your muscles will let go of this water, in turn bringing your weight down.
The scales used in most gyms work on bio-electrical impedance – basically the amount of resistance to a very small electric current passing through your body, and then calculate body fat based on the assumption that muscle is wet, and fat is dry (and water conducts electricity). So if you are carrying less water, the scales may very well report a higher body fat reading.
Note: a fluctuation of 2-3% could quite possibly be just water content
Energy in, energy out…. The body normally burns a mix of carbohydrate, as glucose, and fat for fuel. How much of either depends on your physical activity and if, or what you have eaten recently. When you use more energy than you take in from food and drink, the body burns stored fat and carbohydrates, and then even protein, to fuel your everyday activities even if you are not exercising.
If you are not fuelling up enough, that is, not eating enough for your daily activities including exercise, your body will turn on itself and start to eat away at muscle for energy, also your body may decide to get conservative and drop your metabolic rate if you have had a day or more with no exercise.
Inconsistent eating……… also impacts on the scales, with regular exercise and eating as your main pattern you will see results, by this I mean, exercise at least twice a week for 1 hour or minimum of 4 x 30 minute sessions a week and eat 5 small meals per day, every day. This will keep your body fuelled and metabolism high.
Some suggestions for effective Fat Loss……………
Increase muscle with weight training. Extra muscle helps to burn more energy at rest, even if only a little. This is called the resting metabolic rate or RMR. Extra muscle will also burn more fat in an active phase, so having more muscle will definitely help burn more energy and fat.
Lift heavier weights….. the weights workout should be at a moderate pace, with the number of repetitions kept between 10 and 15. This is a range that should provide strength and bigger muscle growth, which is called hypertrophy.
Do aerobic exercise. Considering how much energy you would use in an hour of either type of exercise, weights or cardio, you should do some consistent aerobic or cardio work to burn fat.
Try high-intensity cardio….. High-intensity exercise, in short bursts, will increase your metabolism and get that fat moving in the post-exercise period. Circuit Training Programs……Combining weights and cardio in a circuit interval session is also an excellent way to burn fat. Although you have your own program for each session don’t be afraid to ask your trainer to mix it up on occasion.