For liability reasons, I would insist the client get clearance from his/her doctor before enganging in any type of activity. It’s better to be safe than sorry. It’s for their own health and safety above all. If any of my clients refuses to get clearance for any medical condition they have or develop while I’m training them, I refuse to train them.
Don’t feel bad for clients who refuse to get medical clearance; sometimes they have to take responsibility for themselves. We are there to help them, not to put their health in danger. There are medical conditions than can grow from a ‘small’ issue to something more serious, so it’s better to know what we’re dealing with anyway. While many trainers know a lot about the human body, we’re not qualified to determine whether a medical condition is serious enough to limit exercise, regardless of whether or not a client tells you they’ve been cleared medically.
In addition, I look at obtaining medical clearance as an opportunity to network with medical professionals. It gives credibility to our industry by demonstrating responsible, ethical practices, and it may end up in future referrals of clients.