Running an ultra while working in a construction/physical labor job?

Hello,
I ran a marathon this year and am interested in trying a 50k next spring. However, I recently began working in a very physically demanding job. Has anyone else done something like this?

I feel I would need one day a week of little or no physical activity - no work, no running. So that would mean a weekend day completely free. My understanding is that ultras require two long runs per week. If I was in a sedentary job, I'd do a long run on Saturday, and another on Sunday, and then recover on Monday as I sat at my desk at work. With the work I'm in though, it would be more like: do a long run after work on Friday, do another long run on Saturday, and then take Sunday off.

But that would essentially mean, at the height of the training, working a full day of physical labor on Friday, running 20+ miles Friday night, and then getting up and running on Saturday. Am I nuts? Are you nuts? Have you done this?

It sounds like a lot to ask of yourself. I haven't tried that kind of schedule before. You'll probably just have to play it by ear - cut it back if you're too exhausted or feel an injury coming on. Makes sense when I say it, but easier said than done. If your physical labor job requires a lot of walking around, you could actually count some of that time. Plain old consecutive "time on feet", whether walking, hiking or running, is one reason for those back-to-back weekend runs. You could also try spreading some of those miles throughout the week. Total weekly miles is arguably as important as those long runs (maxing at 50-70 miles/week is enough for 50k - 100mi races). Good luck!

My job as a letter carrier is physical and has me on my feet, walking, most all day five to six days a week. I usually run 3-5 miles, sometimes 5-8 miles, 3 to 4 days a week (most often in in the evenings after work) and my long runs of usually 10-15 miles (and occasionally 15-20 miles) are usually on Sundays. I find the walking and time spent on my feet at work helpful in that it can work as active recovery after hard runs. The downside is that I believe the job is more stressful on my knees and hips than is the running. I do frequently take one or two days off from running after long/fast races or exceptionally hard efforts but only rarely take a complete rest day (no work or running). I've run three trail half marathons and a variety of 15-18K races in the approximately one year since I started running. I also completed my first 50K just a couple of months ago with a time better than I had planned or hoped. My average weekly mileage has been approximately 20-25 miles. The longest I've run after a full day of work is 12.5 miles (which was not really planned) but I've generally kept weekday runs shorter (but frequently more intense) due to time constraints and need to get proper rest more than just distance concerns. Yes, according to my wife anyway, I'm nuts. But it is do-able, for me anyway. Everybody is different, though.