15 to 20 seconds, ending in coughing.  I‘m a 61 year old man, obese, hypertensive, persistent dry cough, walk 5 miles once a week.  I’m much worse at this than I remember myself being.  I’ve got an appointment to talk to my doctor on Monday; I’ll bring this up.

Well, that spoiled my morning.  I was having a wonderful morning thinking about trisecting angles and Clifford algebras.  Now I’m fretting about my health.  I used to fret a lot, but I mostly got rid of it using a mixture of Stoic philosophy and Bupropion.  But it still happens once in a while, and this is one of those whiles.

OP, don’t feel guilty.  You’ve done nothing wrong.  I feel that I have to say this only because some people are so scrupulous that they would feel bad.

2:25 with hyperventilation and resting.

I pushed myself pretty hard and got 63 seconds.

Context:

• 31 year old male
• Consistently walk 10k+ steps/day
• Used to play a lot of basketball but stopped in early 20s
• Racquetball once or twice a week
• Lift weights once or twice a week but periodically go weeks without lifting
• I've been trying to get started with zone 2 cardio but haven't really gotten going

1:34 but I took a deep breath first and had to watch a video to distract myself. I'm also unsure if I didn't breathe in a tiny bit during that process. 

EDIT: I'm quite unfit, though for the past couple of years I've been doing 40-minutes to 1 hour of cycling every day, with 2-3 hours every week or two. Though I haven't cycled in a couple of weeks. My bike got a flat tyre :(

62 seconds.

68-year-old woman
take a 45-60 min. walk every day
go to fitness bootcamp 2x/week

When I was young, in good shape, and doing a fair bit of snorkeling and scuba, I was able to pass 2:15 minutes consistently, and once or twice to 3:00 (but that was VERY uncomfortable).

I just tried it, and tapped out at 1:31 after enough suppression of breathing movement (diaphram pressure blocked by throat) that it was annoying.  If I'd been willing to really push I likely could have gotten another 10-15 secs.  Male in my mid-50s, not terribly active.  I did less than 30 seconds of hyperventilation (about 4 deep exhale/inhale cycles) first, and held the final inhale.

1:15 with the use of some distraction and breathing techniques. Mid-20s male in decent health but asthma.

I remember pushing to 90 seconds at one point when experimenting with some body control techniques, but that was a couple years ago and I'd probably have to take some unhealthy measures to repeat that nowadays.