just thought i'd let you know that sainsbury's have a range of exercise gear in. cropped and long bottoms, cropped tops and sleeveless tops. i bought my usual size a 14 and it's a bit big. they go up to a size 22.
i paid £12 for the cropped trousers. next do a range too. they' got 1 pair of black bottoms up to a size 28 and the some of the rest of the range is up to a size 22 both regular length and long length too. not a bad price around the £18-20 range. tops also go up to a size 22.
I actually work in the clothing department at Sainsbury's We have some great exercise stuff. Pro-tip: for the fancier exercise stuff, look in the general goods section - we don't keep it all on the clothing department