How do I tell my bf [27M] that I [24F] am upset with how much time he spends at the gym?

we have been together for 5.5years. We both work in healthcare and work 3-4 14hr shifts/week. Our schedule changes every week. We live in a large house with my cousin [30M]. We have a 4yo high energy hound dog.

He has been doing MMA his whole life, and is fairly active normally. During nursing school he gained a lot of weight. We’ve both gained weight over the years, and are actively working to be healthier (gym multiple days per week, clean eating, all the things).

My issue is that he has started going to the gym every day at 3am before work, so he goes to bed around 8:30-9:30p. He is not sleeping enough, which makes him very cranky. On the days that he doesn’t work he wakes up and goes to the gym for 2ish hours, then comes home and does nothing for a few hours, and then goes to a 3hr jiu jitsu class. I am very proud of how dedicated he is to his fitness journey, he has made so much progress.

I’m also starting to feel upset and frustrated, because we never see each other anymore, and his gym time is his 100% priority 24/7. He has stopped contributing to shared household responsibilities (running the dishwasher, taking out the trash, feeding or walking the dog, mowing the lawn, cleaning, etc). I’ve addressed it, but he says that he’s just putting all his effort into the gym right now.

All of his time is allocated to working out and doing self serving things, and then as soon as he has free time he expects me to drop everything I’m doing and spend quality time with him. If I’m busy he guilt trips me.

I’m sick of picking up the slack and feeling like our relationship isn’t a priority. He is sensitive to criticism, and easily gets defensive.

How do I express my frustration and set boundaries while still honoring the self work he is doing?