Why does the weight come back?
I keep reading articles lately that claim a particular programme of dieting or exercise "doesn't work" because after a person achieved their target weight or finished their exercise programme the weight crept back on until they were right back where they started. This really grinds my gears as simply put, of course it does! This doesn't mean that the diet or exercise didn't work. To explain why here is a simple explanation of how weight loss works:
Your body requires a certain amount of energy daily. Your heartbeat, breathing, digestion, and maintaining your body temperature all use energy which we measure as kcals. This figure is often referred to as BMR or Basal Metabolic Rate. BMR is your rock bottom figure for your body to survive in its current state. Add a bit extra to reflect your activity level (e.g. sedentary - office worker, lightly active - store worker) and we have the approximate amount of calories you need each day to stay as you are while performing your daily activities.
When we diet we usually aim to reduce our calorie consumption to a few hundred calories below our daily calorie requirement to create a caloric deficit. This means that your body has to use stored body fat (and, unfortunately, muscle) to make up the shortfall in energy so that your body can continue to survive. Throw in some exercise to burn a few more calories and keep muscle from wasting and this in essence is how we lose weight (Or more properly burn excess fat to improve our body composition.)
So far, so simple. If you consume more energy than you need then your body stores it away for later in the form of body fat; If you consume less your body makes up the difference by using stored fat and muscle tissue as fuel, reducing your overall mass.
As your body mass and composition changes, your calorie requirements also change. As you lose fat mass your body needs less calories to survive meaning your weight loss will slow until the amount of calories you actually need daily is the same as your current level of consumption meaning that you are no longer in deficit. If this is your target weight then mission accomplished. (If not you have plateaued and will need to recalculate your calorie requirements to get things moving again.)
If you finish your diet and start eating like you did before then you will be in calorie surplus and start packing it back on again straightaway and before you know it you'll be back where you started.
Here's the rub. For lasting results: YOU NEED TO KEEP DOING IT!
If you need some help navigating the confusing world of fitness and fad diets please give me a call. I'd be happy to help you with a free consultation.