Louis van Gaal expressed his concerns about United's pre-season tour on its first leg, in Los Angeles, per Simon Stone of BBC Sport.
You have to travel distances, you have to fly a lot, you also have jetlag - that is not very positive for a good preparation.
It is a theme he returned to last week. When asked at the Friday press conference about the injury to Luke Shaw. In the six reasons he listed for Shaw's injuries, he cited jet lag as one of them (h/t ESPN.co.uk).
Back in July, Van Gaal also said, per the BBC story above, "The tour was already arranged so I have to adapt—and Manchester United shall do everything to adapt to my rules for good preparation." It is clear that the good preparation of which he speaks has not been possible this summer.
United have a significant number of injuries to players in the first-team squad, a number of which were picked up on the tour. This contributed to United's defeat to Swansea and if the poor form does not improve quickly then it could have a lingering negative effect on United's season.
Next year should be different. For now the travel is a regret the club will have to live with.