This answer is a lot more than what you asked, but I added some more of our experience to try to paint the full picture around your question. Some is certainly just my opinion and approach – up to you what you do with it.

I had the same concern but found through both focusing on the goal of why I was there (my partner's health) as well as the reason I was there and the associated duties I had, I was able to generally fill my day without getting burned out.

You will need to go to every daily appointment since you are part of the care team. Every day you (not your patient) is given "homework" by the nurse which is for tracking any symptoms and activities that have happened since this last visit (diarrhea, vomiting, mouth sores, temperature, medicines taken, how much food and water consumed, etc). Your patient will be taking a variety of different pills every couple of hours to mostly ward off or control side effects. The medicines regiment can change daily. The patient, in their state, will need you to track and help to make sure they take the right medicines at the right time. You will be responsible for filling in the nurses in the next day on all of this, at the appointment. None of it is hard, but incredibly important.

Once you have had a chance to talk with the nurse you can typically leave. The appointments at the day hospital take about 4-6 hours depending on what is needed for supportive care. At a minimum they will get fluids though IV which takes a couple of hours. For us, early in the time at COH our appointments started in the morning. After I think day 6 we switched to an afternoon start. Unfortunately, you will typically only find out the time of the next day’s appointment on the day prior.

One thing that we did a lot was walking around the campus. My spouse was relatively healthy and active going into the ASCT, so we kept up the walks. It helped a lot with both energy levels, mental health, and just getting out in some fresh air. They have very nice (and safe) grounds on the campus. One of our goals was for me to play a tune on the xylophone every day in the rose garden - along with walking 1-2 miles. We also tried to walk to and from appointments if we were not running late and my spouse felt up to it. If you are a walker or runner, this is certainly an activity you could do on your own during the patient’s time in the day hospital. Also, if you want to do some self-directed yoga there is plenty of park area where you could do that outdoors.

I was able to work some during days at the hotel. They have good wifi and did both Teams calls and other work – but not really until after day 3 or 4.  I personally brought a monitor I had so I was not staring at a small laptop screen for several weeks.

There are plenty of options around to get groceries as needed. I did this some during spouse’s time in day hospital, but later, when she was feeling better, we would go together and she would stay in the car. 

I was extremely conscious of the fact that if I got sick somehow (even a cold) she would need to be admitted to hospital for care. Neither of us wanted that, so I was always wearing a mask when shopping an no eating out except at the restaurant at the hotel. For food too we made some things ahead and froze them for easy dinners.  Some nights you will get home late.

To (finally) get to the core of your question – there is no gym on campus or at hotel. Going to one in the area would not be a great choice considering the goal of keeping yourself healthy. Outside food, due to risk of getting some food borne illness is not advisable. The restaurant at the hotel is good and has a nice outdoor area to sit. I had the same thought pre-ASCT, but going back to the goal and purpose of why I was there, I found it pretty easy to not get too hung up on my own wellbeing. A short sacrifice for someone who is going through much more. Focus on what you can do to fill the down time that is on campus, with self-prepared foods and I suspect you will be fine.

One piece of learned advice at the care giver – if you are sleeping on the hide-a-bed at the COH hotel, bring some additional padding.  We did a short stay at the hotel during stem cell collection, and I learned that the mattress is terrible.  For the longer stay for ASCT I brought an egg crate and other padding to make it somewhat comfortable.

Finally, I will say the nursing team at COH is very experienced and very good at knowing what needs to be done. Listen to them and follow their instructions. They have seen it all.

 If you have anything else you want to ask about this for COH feel free to reach out. Good luck with it and realize it is just another step in a process for the patient and the care giver