people who express interest in personal training but want to delay the start are really saying that they are not ready now. You cannot persuade them to get started but you can ask them whether the would like to be included on your mailing list for occasional emails (such as the IDEA newsletter). Chances are that they will say ‘yes’ to that, and then at least you have some point of contact for a possible future opportunity.
I agree with Karin… People who indicate an interest and then do not follow through could have any number of reasons, but they may not be ready to make a change. They could be thinking about it, but not ready to commit. You may find that to be a rather common thing. You can inform them of your services and keep them posted on any new events or specials to encourage them, but they will commit when they are ready.
It sounds like they’re in the contemplation stage, not ready for commitment. What I do is tell them the days and times that I’m available to train and that if they wish to get the exact time they want, they need to start now. I don’t hard sell or anything, I just don’t have a lot of hours to train one on one, so I am unable to hold spots open for clients. This also goes for clients who consistently cancel on me; even though they pay me for cancellations less than 24 hours in advance, I’m not helping them if they’re not coming!!!