Theophylact of Ohrid

Yet even here He was not hidden from those who sought Him. On the contrary, the people watched so attentively lest the Lord be hidden from them that they went ahead, that is, outran the apostles themselves and went to the place where Jesus intended to rest. So you too should go ahead of Jesus: do not wait for Him to call you, but rather hasten forward yourself to anticipate Him.

Commentary on Mark ↗

Bede

And they saw them going away, and many recognized them, and they ran afoot from all the towns, etc. By saying that they outstripped them on foot, it is shown that the disciples with the Lord did not reach another shore of the sea or Jordan by ship, but having crossed a certain strait or lake, they went to the nearby places of the same region, which the natives could reach on foot.

On the Gospel of Mark ↗