Prior to your trip, signing up for a travel insurance policy to cover theft, loss and medical problems is a good idea. Be advised, however, that some policies specifically exclude dangerous activities, which can include scuba diving, motorcycling, and even trekking.
You may prefer a policy that pays doctors or hospitals directly, rather than you having to pay on the spot and claim later. If you have to claim later, ensure you keep all documentation.
Check that the policy covers ambulances or an emergency flight home.