Ladies who are very large in build may experience mobility and exercising problems that don't affect smaller plump ladies. I've put together just a few tips that might be of help.
Upper body strength
One's strength tends to build up if you have a built-in weight lifting regime of carrying your own weight. A common problem, however, is that upper body strength might be insufficient to allow you to be agile, or to be able to carry out various exercises if you are trying to keep fit.
The solution to this problem is finding a way to build up strength in your arms, back, shoulders and chest. Press-ups (push-ups) are not an option for many large ladies, but an alternative is the wall press-up. Face a wall, press your hands against the wall at roughly shoulder level, and do the press-ups in an upright stance. If that is too easy on your arm muscles, then you can lean forwards towards the wall, and adjust this angle of lean to suit you. Weight training your arms will help too. Ladies who have tried this, find that they are then able to do other exercises that their slimmer friends do, and it improves the quality of their daily lives.
Lower body strength
Lower body exercising might still be needed depending on your daily activities and how much exercise you get doing chores etc. Stretching one's muscles daily can help. Standing upright and doing knee bends. Lying down and doing leg lifts.
If you can find an aqua-aerobics class locally, then this is a popular approach for doing exercises that might normally be too strenuous. It will help to give your lungs and heart a workout without over-doing it or putting too much stress on any part of your body.
Back pains - avoiding them
Back pains often result from posture when seated. The shape of a very cuddly lady can be quite different from most ladies and this shape can tend to modify one's posture. It is important to find a way to sit that allows your spine to be fairly straight, while still getting support from seat cushions. If your seated height is quite tall, then this can add another problem if you are working at a computer. It can help to raise the height of the computer screen and keyboard, so that your head is level and you don't need to slouch when working.
Muscle and fat
More muscle mass helps to use up energy rather than it becoming stored as fat build up. If lowering your level of fat is what you want to achieve, and if this is proving very hard, then building up strength may help. Just remember that muscle is more dense than fat, so a reduction in weight might be less than your reduction in volume.
Swimming is a popular form of exercise for larger ladies, as the water supports a lot of body weight and makes exercising less punishing on the joints. You might prefer to go to women-only sessions at a pool. It may also be worth checking out the facilities at the pool, including the quality/strength of the pool ladders, before going for a swim.
Low impact exercises
If you are fortunate, you might be able to find some local exercise classes that offer low-impact exercises. They provide exercise without giving one's joints a bashing. Your local doctor/surgery might be able to recommend one, or even run one themselves. Alternatively, tai-chi exercise routines may be suitable for you? If you have a good doctor, then he/she might also be able to offer advice on exercising that will suit your physique.