Losing weight and getting fat

Two years ago I made the decision to actually lose weight and hopefully get faster on my bike. This was brought about by cycling with Dai and watching as his fitness and speed on the bike came quickly up to my own, and then briefly matched and passed me. I wasn't having any of that! So I set about doing something about it. Having a smartphone helped a lot, as there are a raft of apps out there to help you lose weight and get fitter. The one I chose at the time was the Livestrong calorie tracker app, and a website that outlined a core workout on a weekly basis. Using those two, I started tracking my calorie input, and doing regular core exercises at home. Combined, I quickly lost weight and began to feel the benefit of the core workout every week. Over time, I've not been very regular with the core workout, but I have kept up the calorie counting, much to the sometime annoyance of the family as I work out the calorie count at mealtimes. I've allowed myself 2300 calories a day. I know some of my work colleagues will disagree, but I do have quite a physical job, and with my regular exercise regime, can sometimes get through over 4000 calories a day. Obviously, if you're burning that much, you have to put it back, otherwise you'll lose weight. So, don't put it all back and you do indeed lose weight. My starting weight was around 18 stone 2 years ago, and I was just over 14 stone when diagnosed with cancer, so its been working a treat. I've been getting a bit quicker on the bike as well :)
Now, in the last few months, I noticed a 3-4 lb drop in my weight that couldn't be down to doing more exercises or eating less, but I didn't pick up on it at the time. In hindsight, that was probably a warning sign that something was amiss. My weight had settled around the 207lb mark, and wasn't budging.
Until now.
I've now to put on weight, and quickly. I'm in for a course of chemo in the next week or so, which by all accounts will knock my appetite for six, make me feel sick and sap all my energy. So I'll not feel like eating or exercising. Not what I want to hear. However, I'm looking on all my past weight loss and fitness gain as the means to fighting and beating this cancer. Here's me thinking I was training just to get faster on the bike, when in actual fact I was training to beat this cancer. I'm fit enough now to take it on and beat it.

So, after a few days of rest after my Laparoscopy, I've been back to the gym today to start to regain my lost fitness from the past few weeks of tests and probing. My calorie intake is up to 3200 a day to gain weight, and I'm counting the days when I can get out on my new bike and start climbing hills again.
I'm not letting this crap stop me doing what I love. Bring it on.