exercise and pain

highlandpony2002

How can I increase my exercise when I am in a lot of pain due to needing a knee replacement and suffering from fybromyalgia At present I walk round the ponies field with a wheelbarrow for 30 minutes per day and walk the dog twice for about 20 minutes per day but this is my normal level of exercise and appreciate the best way to lose weight is to increase this above the level your body is used to