If we look at humans as climbers, we’re not half-bad:
A fascinating brief study published in Science (May 16 2008) shows the cost of climbing a meter per unit of body mass is essentially the same over non-human primates and humans (Hs in the figure). The data are all matched for climbing speed. Walking efficiency is also indicated in yellow.
We homo sapiens are pretty efficient climbers, though being the largest of the primates we may be a bit slower at it. On the other hand we are more efficient in walking. The reason for that is we have longer legs per unit of body mass.