Best body ever!

You can lose weight while swimming a mile a day but you could also maintain weight or gain weight - it's your calorie balance that determines if you lose or not.
Lets guess that you burn 350cals with your daily swim, 10 sessions to burn the equivalent of a pound of fat, 420 sessions to burn your 42lbs. That shows how difficult exercise for weight loss is, I wouldn't call it a myth but your PTs have a very valid point.
Diet, and especially size of your diet, is far and away the most important factor.

If your swimming (or other exercise) pushes the boundaries of your current capabilities you will adapt by becomming fitter and stronger. Not sure what you mean by toning as that seems to mean different things to different people. If it's the appearance of being fitter then remember any muscularity changes tend to be limited, slow and are also hidden under your excess weight.
Exercise is great (I do a lot of it!) but you need to be realistic about what it can do and especially the timeframes involved.

MyFitnessPal also intends that you don't use exercise to boost weight loss, trying to reinforce that exercise is for health/finess/enjoyment for life rather than a limited duration diet strategy. Far too many people pick an aggressive rate of weight loss, then try to make it faster with exercise and simply fail and give up as they have made a hard task even harder. Have a long think about sustainability.

Congrats on your courage in making major changes in your life. :flowerforyou:

MaltedTea wrote: »

lucytalbot94 wrote: »

*snip*
So, I have recently escaped an abusive relationship in which I was force fed and discouraged from attending the gym
*snip*

Any advice would be very much appreciated!

Beyond the nutrition and exercise, counseling. Mental health and physical health go hand in hand. Glad you're on your way to getting better.

This was my first thought.
OP I didn't have the experience you had, but did have low level anxiety my whole life. It wasn't till I got counselling I was able to finally lose the weight. Going through abuse such as you had I highly recommend looking after your mental health as well as your physical.

I also have concerns about your approach. It's best to start small and build up. There is no need to cut out whole food groups, as long as you eat in a calorie deficit it doesn't matter what you eat. Starchy vegetables and breads have nutritional value as well. Sure cut down on these but I wouldn't eliminate them all together straight away. I'd start by portion control. Having the same foods., just less. This is because generally a complete overhaul of your diet doesn't work, most people fall off the wagon and go back to how they used to eat. Making small changes over a longer period of time does.

Remember slow and steady wins the race.