Subtheme	Study	Direct participant data	Author description of data
Capacity to exercise	Campbell 2001	"When I did the exercises in the beginning, it wasn't painful with the tape on, so I think that was how I was able to get on with them so well…whereas if the tape came off and I didn't put it on it was more painful." p.135. "I see people come in with arthritis and I think oh…god they are in terrible trouble and absolute agony and I think well I've got nothing to complain about." p.135.	The perceived severity of knee symptoms was an important factor in motivation, with those experiencing severe pain or loss of mobility (or both) being most likely to continue to exercise. p.135. The existence of other comorbidities, comparison with other people with more limiting disease or a stoic attitude to knee symptoms all seemed to be associated with an attenuation of the motivation to comply. p.135.
	Hendry 2006	"Anything that would jog or jar my knee would really hurt." p.560. "I can't swim anymore because breaststroke is bad for my knee." p.560. "It's hard to get going on a bike and very painful." p.560. "I've reached an age where exercise doesn't help, I just get tired." p.560 "I'm not fit and agile enough to do exercises." p.560.	Participants' ability to exercise was limited by the pain and stiffness in their knees, which restricted the type and amount of exercise that was possible. Ability was also limited by a perceived general lack of physical fitness, sometimes attributed to old age, as well as comorbidity including angina, lymphoedema, congenitally malformed hip and osteoporosis. p.560.
	Hurley 2010	"…Well there's hardly a good day you know. I mean I just make the best of it. I don't try to you know, let it get me down. Although I have pain, I'll try and do what I can do you know rather than to just say' I am in pain I can't do that'…" p.5. "…I'm good at going up stairs, it's the coming down I have difficulty with." p.5. "…It's very tiring walking round shops…Some days I just sit here most of the time because it's too painful to move…" p.5. "…my daughter has to be with me to have a bath…I can't move, I can't push my legs down from my knees, they won't function…I can't do shopping…my daughter does it all, yeah. You know, I mean she's ever so good to me…She does things, she does this of a morning before she goes to work…" p.5. "…I don't have a bath. I can't get up and down…I stand in the bath and wash down." p.5.	Pain, muscle weakness and fatigue after common activities of daily living impaired people's physical functioning and mobility. They stoically tried to carry out their normal activities, but often had to adjust or avoid activities (e.g. showering instead of bathing) to cope with their limitations and maximise their independence, and depended on family and friends for help with essential domestic and social activities (e.g. shopping, housework, gardening, transport, bathing).
	Moody 2012	"Umm, I suppose the things that sort of do prevent you are if you get ill. One thing, that's probably the only thing would be if I got ill…I probably wouldn't be able to go, but only that would keep me away." p.67. "Well for me, at first that's why I missed some of them. I couldn't go more than one because I was just so tired the next day and would sleep so sound, you know at the night‐time, that I couldn't always wake up early enough to get myself organized to get the bus." p.67.	1 barrier to ongoing participation was that of illness. For some participants, fatigue was an issue.
	Petursdottir 2010	"The effort to get clean afterward is really hard…You just don't have the energy to take a shower." p.1020.	Pain was a crucial issue in the interviews, being a barrier in itself, but the hope of decreasing the pain by exercising turned out to be a major facilitator to encourage regular exercise. The participants described the difficulty of having to constantly adapt their exercise pattern to pain that could vary from day to day and even be too intense to be able to exercise at all. p.1020. 1 woman expressed her deep concern regarding how pain and fatigue led to difficulties with personal hygiene. She believed that people with chronic pain hesitate to exercise because they do not feel up to taking a shower afterward. p.1020.
	Thorstensson 2006	"You need to have the will to do it…when you are well you don't do it, and when you need to do it, then it hurts and therefore you don't do it (laughter)." p.55. "And even if it hurts a bit, one should not give in but of course sometimes you can feel sore or aching joints afterwards, if it hurts when doing certain movements…of course it hurts, even when exercising." p.55.	‐