Hello Steph, I've done cleanses throughout the years, including the Master Cleanse which is the cayenne and lemon. I have some thoughts about cleanses that I'll share (I am not a doctor or nurse or anything at all so keep that in mind
One thing I've always done is to make sure my doctor knows what I'm doing. It sounds like you are healthy so it probably isn't vital you get your dr's direct supervision but if you've taken any medications in the past few months or had anything funky going on it might not be a bad idea to go in and talk to her about it first.
If you are healthy and just want to pretty much push a reset button there isn't much reason to do a harsh cleanse that includes a lot of fasting. Some great gentle cleanses that do a lot for your body can include a variety of foods and smoothies (these are easiest for me to stay committed to for the entire time period). The cayanne and lemon cleanse is very harsh (a lot of bm's) but my dr ok'd it for me for that particular time when I had been sick for quite a while. I loved the results after it was completed but felt horrible most of the time I was on it. I think if I hadn't been so desperate to feel better I wouldn't have stayed committed to it the two weeks.
When I do a cleanse I do not work out at all, in fact I purposely schedule a cleanse for a time when I can rest a lot and don't have to put too much mind power into anything. Usually I feel pretty lousy the first several days into it and get headaches and feel irritable (even on the ones that don't require fasting) so I try to take it easy. I have always felt incredible after cleansing and usually adopt certain components of a cleanse if I feel they really speak to my body (for example, I drink lemon in my water a lot now after the Master Cleanse because if felt so good to me). One thing I have learned is that any weight that has come off because of a cleanse always returns afterwards so I don't even pay attention to that aspect. I hope this is useful to you.