When it comes to weight loss, we are all familiar with the whole “weight loss is 80 percent diet, 20 percent exercise” statistic. Although the actual statistic or breakdown has been debated, split, what we really need to understand when it comes to losing weight and keeping it off, is that diet and exercise have two very different roles.
To lose weight, we need to burn more calories than we eat, on a daily basis; we want a caloric deficit. To get this deficit we need to burn more calories or we need to eat fewer calories. When it comes to weight loss, the exercise part of the equation refers to us burning more calories, and the diet part of the equations refers to the decrease in calorie consumption.
When it comes to healthy weight loss, the general rule of thumb equates to half a kilo weight loss a week; this involves a caloric deficit of 500 calories per day, every day. To achieve this weight loss, we can either run and sweat it out for approximately an hour, everyday (who has that much time everyday?) or you can just change you daily morning coffee order, to an option that has fewer calories? I know which option I would take. Calorie restriction seems like the easier alternative.
Of course a high-volume physical exercise routine with no change in diet may still lead to weight, however without actually changing your diet, the weight loss will be slower, which can be discouraging.
Although the caloric burn we get from exercise, in the short term, is not that dramatic, exercise is still necessary for weight loss. Exercise is critical as it makes sure we are losing fat from weight loss, and not muscle or water. Weight loss without exercise has been shown to result in a 30-40% loss of muscle mass, from total weight loss. Remember, muscle mass is our greatest modifiable factor affecting our basal metabolic rate, the number of calories we burn each day, to help us stay alive. Exercise not only helps us keep muscle mass and help prevent muscle mass in weight loss, exercise, particularly resistance training actually builds muscle. So exercises that focus on building strength and muscle is key.
For long lasting weight loss and weight maintenance, diet and exercise together is necessary. I suggest you focus on a mild calorie deficit, of about 500 calories a day, but add in a few short, resistance style gym sessions every week to help you build and maintenance muscle mass.