Intermittent Fasting With a Physical Job and Chronic Pain: How It Went for Me

By Brian Hupp · October 12, 2026

I've worked a few physical jobs over the years, and they were hard. The job I have now has me walking a lot. I've also worked in pain for years, and for part of that time I was fasting.

I went from 520 pounds to 200 by changing when I ate (the whole story is in How I Lost 300 Pounds With Intermittent Fasting). I'm not a doctor and this isn't medical advice. I'm leaving out where I worked, because it doesn't change anything here.

Pain at work was already normal for me

I pushed through pain at work for years. I'd done it so long that hurting on the job was just normal. That's what I did, and I'm not recommending it to you.

The pain got less as the weight came off

As I started to lose weight, the pain got less. Everything is easier now that the weight is gone, and work is part of that.

I still fight pain. I have ordinary wear-and-tear arthritis in my knees and back, and that's a different story for another day.

The rheumatoid arthritis is its own thing. Those symptoms went into remission after the weight loss and the change in how I ate, and my doctors took me off the RA medication. Being off it doesn't mean I'm cured, and I can't tell you fasting is the reason.

Where my bad days came from

I'd get bad days sometimes. They came from one of two things. Either I ate early in my window and had nothing else that night, or the meal I ate was too small.

Your body still needs nutrition. Most days I eat one meal, and it has to be a real one. What that meal looks like is in What I Eat While Intermittent Fasting: Whatever I Want, Just Less.

Dr. Krista Varady is a nutrition professor who runs fasting studies. In an NIDDK interview she says: "people do lose a bit of lean mass; that's just a natural result of weight loss."

She's talking about the people in her studies. I can't tell you how much of that happened to me. I read it as one more reason to eat a real meal when the work is physical.

If your job is physical

I can't tell you how to fit a window around your shift, because jobs are too different. What went wrong for me was eating too early and eating too little, so those are the two things I'd watch.

I started below 12:12 and it took me almost two years to get where I am now. Starting with too long a fast is the first one in 5 Intermittent Fasting Mistakes, Including the One I Still Make. If you want help lining a window up with work hours, Planning Your Eating Window Around a Normal Workday goes through it.

Talk to your doctor first

Fasting isn't right for everyone, and I don't want to push it on anybody. If you have a health condition, take medication, are pregnant, or have a history of disordered eating, talk to your doctor before you change how you eat.

That matters even more if you live with pain. Some pain medicines are meant to be taken with food, and your doctor or pharmacist knows which ones. If getting lightheaded at your job could get you or somebody else hurt, bring that up too.

Before You Try Intermittent Fasting has questions worth bringing to that appointment.

If you want to try

You don't have to buy anything to start. I didn't. The free Fasting Readiness Quiz is an educational tool that helps you think about where to begin. It can't tell you whether fasting is safe for you. The free Fasting Tracker keeps a history of your fasts on your own device.

If you want more than that, Finding Your Window is my $9.99 PDF guide. It covers five fasting windows, with common mistakes and what to expect in the first weeks, and has tracking logs. It is not a meal plan.

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