I’m not training to become an Uber[wo]man; whenever my sleep cycle turns polyphasic, it stems more from insomnia than any drive to maximize productivity during my waking hours. Still, the habits of night owls, nurses, and early-morning news anchors interest me. I think maintaining a schedule so different from that of the general public is admirable (doubly so if you can stay sane while doing it). Dipping a toe into these waters out of curiosity rather than necessity, I decided to spend a week working out at my local gym reverse-Cinderella style—just after the clock struck 12am.

I generally head to the 24 Hour Fitness when everyone else does, between 5pm and 7pm—prime time for taking in the latest gym fashions and enjoying gratuitous grunts from the weightlifting pack. It’s less ideal if you’re running late for spinning class and hoping to claim a free bike. So I wondered, would shifting my schedule to late-night cardio improve my overall experience?

Here’s what I can tell you. For one, while nowhere near maximum capacity, the gym is surprisingly populated at this time of night. While the gender divide always seems evenly split in the early evening, after midnight, the male to female ratio is about 10:1—usually around 30 guys and just a handful of women. Many of my female friends would call this favorable.

The post-midnight style (male or female) is hood-up hoodie plus gallon-sized plastic jug of spring water. In short, people in the gym at this hour look serious and are there for serious fitness—not to make friends or flirt. This uniformity had a surprising effect on me: though I could have my pick of any treadmill in the place, I was pretty bored. Turns out, a good 40 percent of my training incentives come from people-watching. Those steely-eyed ninjas were just too focused.

I asked Dustin Ondrasek, fitness manager at my local 24 Hour Fitness, if he’s observed any peculiarities or best practices in the fitness habits of the after-hours gym rat. “I see work schedule as a driving factor for our members,” he said. “Most people who come here late at night are just getting off a shift or maybe getting ready for one. We’ll have people come in with jet lag and some insomniacs, but it’s mostly just people trying to fit a workout into their routine. From a trainer’s perspective, we tend to get our best results from clients in the morning, but that doesn’t mean you can’t have a productive session in the evening, or even later on.” He noted that sleep should be considered above all other factors when changing a workout pattern. “Once your heart rate goes up, you instantly feel awake, and this can make it challenging for some to exercise around the time they need to go to bed.”

This was true for me. While time spent on the elliptical didn’t tax my body any more at 12:30am then it typically does earlier in the evening, the amount of time it took to settle down for sleep afterward definitely increased. There’s no real advantage to this unless you’re naturally nocturnal or occupationally required to sleep in. On the flip side, a pre-dawn workout after a good night’s sleep might lead to a day that feels more full and productive.

What else did I learn from this test of nighttime energy and endurance? Well, the pool and the hot tub are yours for the taking, and in the bathroom, you can spend as much time as you need fussing with the analog scale. You can also really examine your pores in the mirror—no one’s there to judge you. Finally, much like your exercise options, 24-hour gyms are one place where Guy Fieri programming is always available. Guess the sun never sets on Flavortown.

—Lauren Maas

Photographed by Ben Jurgensen.