Tiger ... I've only just been doing this for a little over 2 weeks, so can't really answer you about the loose skin ..... hopefully not !
Personally, I do quite a bit of running about after my toddler, & walking, but I am hoping to buy a 2nd hand exercise bike shortly to help tone up my legs.
The way the diet's been sold to me is that it's a very low fat meal replacement scheme, where you eat shakes, bars and soups which contain all the minerals & vitamins you need each day. You are also encouraged to drink a lot of water, at least 2.5 litres a day. Because you are consuming so few calories, the weight comes off faster than conventional diets and it's therefore ideal for impatient people (like me) who've never managed to quite see a diet through before. Previously, I lost about 27lbs on WW points, and then again on WW No Count ...... but this took me about 4-5 months each time and it was at that point that my willpower seriously snapped and I fell off the wagon well and truly.
Personally, from those past experiences, I know I have a reserve of willpower for up to 20 weeks. Therefore - in theory - if I stick to this diet for that period (and hopefully it will be more like 14-15 weeks) I will have attained my target weight.
Of course ..... if I then go "woopie doo" and start eating rubbish, or eating large portions, again, I will put the weight back on.
Therefore, having got to the weight you want to be, you then follow a so-called "maintenance" plan on the Cambridge Diet, which gradually ups your calorie intake and reintroduces real food, in combination with the shakes etc. over a period of around 6-8 weeks (I think, if memory serves). On the 1st "step", you add xxx more calories and do this for 2 weeks, then you add xxx more calories for another 2 weeks and so on. The idea of seeing through all these steps, is to get you used to making healthy choices and realistic (i.e. not greedy) portions. Common sense really ..... and that basis is the same as most diets, particularly WW ones.
I think the difference though is that while you are re-educating your palate and your eyes, on the Cambridge Diet, you will already be the weight you want to be (which will obviously be lovely) and therefore, hopefully, instead of feeling "deprived", you will be thinking "I need to do this so I can maintain the body I've got", which should be a huge incentive.
I have to admit the diet isn't easy. I can say hand on heart that I've not actually felt hungry, but my God I am bored. I think that says a lot about why many of us eat the way we eat ...... not for necessary fuel, but for all sorts of other reasons, like socialising, indulging ourselves, being plain greedy and mindlessly shovelling something in when we are bored. My fast weight loss so far - and inch loss (I have lost 19 inches overall in 2 weeks) is what encourages me to keep going. I want to be slim, I want to be the person I used to be, instead of something I don't recognise when I look in the mirror and I want my clothes to feel comfortable. I keep telling myself that I can be/do all of that within a very short space of time if I keep at it and that it's not forever.
It's making me think a lot about how I used to eat. Interestingly, I think most about savoury foods now, like mushrooms on toast, jacket potato, spaghetti bolognese and marmite toast ..... but previously, I'd get through chocolate more than anything. I'm not craving that now at all. I wonder if my chocolate guzzling was more a reaction to low blood sugar than a real desire ? I'm surprised I'm not craving sweet stuff ..... maybe because the diet does give you all the vitamins etc you need, my body is actually better balanced than before ?
Hopefully, "after", I can continue resisting sugar by ensuring I eat sensibly ..... like having porridge for breakfast so I don't get a "low" halfway through the morning. I also intend to do low fat wherever possible ..... the thought of low fat anything sounds very appealing when compared to a very restricted diet. Similarily, I will not be greedy in the future, except on special occasions and will not serve up such huge dinners.
Finally, to answer your original qusetion, no, I've not felt tired at all. If anything I feel better in myself, probably because I am getting 100% vitamins and so on and not eating rubbish.-