I have an in home training business and in my own experience for most occasions I would have to say that sending workouts by e-mail is a bad idea. However I can understand that sometimes you get put in a difficult spot. Actually, quite recently I came down with a stomach flu and I did send some of the clients I have been working with for quite a while exercise routines to work through. Now I found that due to the friendship I had already built with them through time they were more than understanding that this was a one time thing. As well I made sure the routines were exercises they were more than able to handle. As for the clients I hadn’t been working with that long I either gave a plan to another trainer I knew to work through with them, or I set a new date for a couple days down the road when I was feeling better.