Pilates is great for core as not only that it works on appearance but it works on the awareness what we can do in our day to day life to engage our muscles to work and tighten, improving our posture.
I do classes in Earlsfield and Wimbledon.
In Earlsfield, it is a part of Prophysiotherapy clinic offer on Tuesday and Thursday night (www.wvpilates.co.uk
) and Wimbledon it is Monday, Wednesdays or Saturdays.
You are free to chose to attend any of it..so you don't have to commit to a specific day but come, whenever you have a time (absolute flexible).
Prophysiotherapy has another Pilates classes for mums where they can come with babies (another lady is doing those classes) and also classes for mums to be (I think it is in a day time).. here is the website that may help: http://prophysiotherapy.co.uk/
I have done Pilates, to keep my body working (loads of injuries) and qualified 3 years ago and I feel massive change in the body so as my "students".. it is awkward and more I do, more I feel body is in a better condition than it was when I was younger..and it is not something one expect to happen.
I also find yoga nice for stretching so very open minded. I would recommend cardio for fat burn but if there are any joint pain.. don't force it.