A pair of Army doctors have embarked on a record-breaking attempt to row non-stop around Britain.

Captains Hamish Reid and Nick Dennison, of the Royal Army Medical Corps, aim to become the first pair to row continuously and unsupported around the British mainland.

The West-based pair are taking on the challenge in their 24ft ocean going rowing boat Komale. They will travel 2,100 miles in approximately 45 days.

The record attempt, which began on Wednesday morning from Lymington Yacht Haven, in Hampshire, will be dominated by tide cycles with the two officers alternating between rowing two hours on and two hours off in open waters and resting together at anchor during the foul tide in inshore waters.

They will find themselves rowing up to 20 hours a day, with sleep patterns dependent on weather conditions.

Capt Dennison, 28, of Bristol, is currently based in Bovington Camp, Dorset, home of the Royal Armoured Corps, and Capt Reid, also 28, who was born on the Isle of Wight, is currently the Regimental Medical Officer of 22 Royal Engineer Regiment in Tidworth, Wiltshire.

Capt Reid said: "We have to condition our bodies to deal with fatigue, discomfort and prolonged exertion. Courage, discipline and integrity are fundamental to the success of this challenge.

"The race will put us in situations we have not experienced before and we shall need to dig deep into our mental reserves to maintain our efforts, uphold these standards and, in the worst case, survive."

Capt Dennison added: "We aim to set a competitive world record and in order to do this our route and navigation through the inshore waters and tides must be excellent and to this end we have undertaken both Yachtmaster and sea-survival courses. Safety is paramount so well practised safety drills and mastery of radio procedure are vital."