It's at least an hour's commute to work

Question

I have a couple of questions related to the meaning of "commute".

Cambridge dictionary: It's at least an hour's commute to work.

The Telegraph: My daily 20-minute commute to work remains unpredictable.

Is this means that the total time required for travelling to work and get back home is 20 minutes, or it means that I need 20 minutes to reach my office?

Also can I use commute with gym? I don't go to gym on a daily basis, and I got impression that "commute" can be only used with places we go routinely like work.

Answer 1

It's at least an hour's commute to work

means it takes one hour to get to work (in the morning). The key being that the sentence specifies "to work", that's only one way travel. In the evening, there's another hour or more commuting home. In total, at least two hours per day.

It would be more ambiguous if it was:

It's at least an hour's commute to and from work each day

but I would still interpret that as at least one hour in each direct, that is, at least two hours total.

My daily 20-minute commute to work remains unpredictable.

This says you need 20 minutes to reach your office. (But if it is 20 minutes in duration, what is unpredictable about the commute? One day it is by bus, the next it might be flying on a giant eagle?)

I do hear people saying things like:

I have to commute for 3 hours a day.

and in those cases, where they don't specify a direction, they have meant three hours total.

You can use "commute to the gym", that is a valid and correct use of the word commute but, in my experience, it is uncommmon. Outside of science and legal systems, current common usage does strongly associate commute with travel to/from work or perhaps school or university.