In reply to Will Legon: Good luck!
There are different products in this area and you could be forgiven for not knowing these. What risk are you trying to insure yourself against?
"Income Protection" cover, otherwise known as "ASU" (Accident, Sickness and Unemployment), is a general insurance product and usually refers to a short-term cover (6-18 months) that is meant to cover your mortgage and other debts. It is generally heavily loaded with commission for the intermediary - generally, I don't think that it provides good value for money.
Critical Illness and Permanent Health Insurance are life insurance products providing either a single lump sum or an ongoing income. These may be more suitable for your circumstances but could be expensive. Check them out.
Different insurers will take different risks and some will heavily load or exclude certain activities. My advice is to shop around and possibly try a couple of the "execution only" IFAs (Independent Financial Advisors) such as Hargreaves Lansdowne in Bristol.
There is a difference between the requirement for "utmost good faith" (without which the insurer can avoid your claim or void the contact) in life insurance and general insurance products. Whilst general insurance requires you to keep the insurer updated of any changes to your circumstances, life insurance requires only the initial declaration to be made and you have no duty to inform the insurer of further changes to your situation (unless stipulated in the contract).