Just as a quick reminder, I’ll list the use of prime symbols for time below, together with some examples.

• Single prime for minutes
• 3*5′@MP (3 times 5 minutes at Marathon Pace)
• Double prime for seconds
• 20*30″@i4 (20 times 30 seconds at intensity level 4)
• Combining minutes and seconds
• 5*3′30″@i3 (5 times 3 minutes and 30 seconds at intensity level 4; I would rather just write 3:30 here, by the way)

If you find primes hard to find on your keyboard, you can just use quotes of course, as in 3*5’@MP.

I got my information from Wikipedia. The relevant page offers a line that actually pretty much sums up what you need to know.

Primes are sometimes used to indicate minutes, and double primes to

indicate seconds of time, as in the John Cage composition 4′33″

(spoken as “four thirty-three”), a composition that lasts exactly 4

minutes 33 seconds. This notation only applies to duration, and is

seldom used for durations longer than 60 minutes. (source: Wikipedia)

There’s some useful information in this StackExchange thread as well.

Thanks for reading!