Last time I hit 180+, I ran a 5k in ~25 minutes. I'll just try to cool down if I'm over.
Exceeding your maximum sustainable heart rate is not more efficient.
On the contrary, the most efficient heart rate for aerobics is around 70% of your MHR.
And to top it off going max HR for a long period can damage your body. Not just your heart. You can tare a muscle or a ligament, etc.
You're reaching that particular bpm by taking a stimulant (something most posters here seem to ignore) there's a good bet you might be above your MHR.
Athletes have high MHR but athletes get health checkups every couple of weeks and have the funding to get the best treatment after they suffer an injury - which most of them do at some point or another in their career.
So unless you're making money out of your work out I'd suggest you mellow down.