Thanks for that advice, I will look up that site.
Ouch about the knee dislocation - when I did first aid course, many years ago, the instructor told us that knee dislocation is one of the most painful injuries you could sustain. I do have a weakness in my left knee (Capricornian trait) so I do need to be careful.
I think I am getting exercise in the leg area from the bike, for part of the session I put the resistance up to maximum, so I am getting aerobic and anaerobic exercise.
To end on a positive note - my weight loss has now hit double figures 10.2kg this morning, and I am only 300g from my target loss for the week ending Saturday, so I should well and truly exceed the target this week. 10kg also represents about an eighth of my total weight loss target, and is halfway to my end of year target. I should reach my final target in time for the London Olympics - sadly, though, 30 years too late