The Hammers, who are embroiled in a relegation battle, have been put through their paces every day since arriving in the United States on Sunday.
West Ham, who are out of the FA Cup, do not play again until March 31, when they will return to the London Stadium to face fellow Premier League strugglers Southampton.
"This break in games gives us the chance to come to train in a different environment and one which we believe will be hugely beneficial to the players," Moyes told the club's official website.
"We've had a long, intense winter period with a lot of matches - 13 since the turn of the year - and little time to rest and recover, so while this trip will offer us the chance to work the lads in testing temperatures on the pitch, it also gives them time to get fully prepared for our important run-in.
"We're hoping that the time away can be really useful for the squad and all the staff as we look to end the season really strongly. With everyone all together, the already-strong team spirit within the group is going to grow and that can only be a good thing ahead of our eight huge matches left in the Premier League."
West Ham's last fixture was a 3-0 defeat to Burnley on Saturday marred by pitch invasions and protests against the club's board.