It was hard, hot and humid but the Scotland players now have a real grasp of two things.
First, how tough life is going to be under Vern Cotter, their new coach; second, how tricky the conditions are going to be when they play their first match under him at the weekend.
Johnnie Beattie, who has the added disadvantage of having missed the end of the regular season with a shoulder injury to leave him a little rusty, admitted after their first flat-out training session in Houston that it had been an exhausting experience even though he had an inkling of what to expect.
He has the benefit of playing in France, so he knows Cotter as an opposition coach and by talking to players who have worked under him. "He will work you very, very hard, train you very, very hard; if you don't perform you will be out the door," he said. "Work hard. Enjoy training, but work hard and win.
"This is the first time we have been together for a long time as a Scotland team. It was the first time we have done it all at full pace, there was a lot of running in the heat. Obviously it was tricky but it was good. Now we've got it out of the way.
"We have only had one session but speaking to the guys who know Cotter, he is an intelligent man, provides a great environment and is a really good coach. He has put Clermont in the position to win games for all those years they have been in the Top 14 contesting finals. If we can go anywhere near that with Scotland, with his structures and ideas, that will put us in good stead."
Beattie also knows a number of players from the United States team, Scotland's first opponents and, as far as Beattie is concerned, they are nowhere near the mugs that their lowly world ranking would suggest. "We know a lot of their key players who are based in Europe, so we know what to expect," he said. "There are some very good rugby players there who are pretty well organised.
"A lot of the boys who play at English and French clubs are talented; not just talented but understand playing within systems and team structures. It will be hard. The rankings are there for a reason but these teams don't get their first-string players for a lot of international matches. If they did have them, they would be winning.
"This is a shot for us to play the first-string side; and it is not a USA ranked 18 that we are facing. It is different, a lot tougher than the gap the rankings points would suggest."