In reply to euanmci:
As far as climbing goes you could probably use:
"(b) to take exercise— (i) alone, (ii) with one or more members of their household, or (iii) with one member of another household;”"
...which was there before anyway. The change in the advice specifically saying driving any distance is OK is probably of more interest.
The other bit is more related to e.g. sunbathing and the likes.
Post edited at 19:29