Andrew Strauss has defended his decision to sit out of England's tour of Bangladesh, saying it is an effort to save himself from burn-out during a busy 18-month period which includes the Ashes series and the World Cup. Alastair Cook is taking charge for the one-day and Test series in a move that had long been anticipated, and Strauss admitted to feeling "pretty jaded" after the two-month tour of South Africa that concluded on Sunday with a heavy defeat at the Wanderers.

Strauss will return to the helm after the ICC World Twenty20 in West Indies - where Paul Collingwood is expected to be England's third captain of the year - for the home summer which includes Tests against Bangladesh and Pakistan and an ODI series with Australia. In October, England head to Australia for the five-match Ashes series, followed by seven ODIs, before heading to the subcontinent for the World Cup in February.

"I am feeling pretty jaded to be honest, it's been a long year with the Ashes as well and I am very conscious of the 18 months of cricket that starts in May with the Ashes tour and the World Cup," he said. "The notion that a captain continues until he is mentally and physically exhausted doesn't seem in the best interests of the side. I am going to get a good rest here and I think I will be as refreshed as I possibly can be for the summer and the Ashes after that, and the World Cup as well."

"If you are going to look for opportunities to rest you have to look at your priorities," he said. "This looks like a sensible opportunity. The Bangladesh tour will be demanding, maybe on the pitch and off the pitch as well, and ideally you'd never miss any cricket, but with the schedules the way they are, it is unrealistic to expect players to play in every game for England over an extended period of time."

Andy Flower, the England coach, agreed that now was the right time for Strauss to refresh himself. "The England captain has a very busy lifestyle. He's constantly dealing with the press, the expectation and the responsibilities of running an England side," he said. "We've determined in his best interests, and consequently the interests of the side, that he needs some rest leading up the 18 months of tough cricket and non-stop cricket that we have coming up."

Strauss's move will provoke much debate and there is a feeling that he is taking a significant risk of disrupting the team's development by standing aside for an entire tour. Despite their heavy defeat in Johannesburg, England's shared series in South Africa showed they are developing as a side, but if the team stumble in Bangladesh - which isn't out of question - the decision will certainly come under fire.

"If I had concerns about that, that would have been a reason for going on the tour, but I am very comfortable with the individuals in the side and the dynamic of the side is not going to change very much, " Strauss said. "Andy [Flower] will still be there and Cookie and I have had a lot of discussions over the years about the side and cricket in general, and we have fairly similar views.

"I think it's being done for the right reasons," he added. "The Ashes and the World Cup are two big priorities for this side and I would never forgive myself if I turned up for the Ashes feeling exhausted, and not giving myself the best chance of performing my job as a captain and a batsman, and not having the energy to keep the players going in some pretty stressful situations. That's the reasoning behind it, others might see it differently, and they are entitled to their opinions."

Cook, who was the vice-captain in South Africa and led the team in the second Twenty20 international when Collingwood was injured, said serious discussions about the role had come up three weeks ago and added it is "an honour and a privilege" to lead his country, but it had not been a position he'd desperately set out for.

This appointment will end after the Test series in March, but Cook is viewed as a strong long-term candidate eventually to replace Strauss and he promised to lead the team in his own style.

"You have to do it your own way," he said. "I have a lot of help around, I am very close to Andy from our Essex days, that relationship has already been formed. If you are not your own man you can't do as well as possible, I can't be another Strauss or [Michael] Vaughan.

"I am probably not a gambling captain, you have to be true to your nature and I think things through before making decisions. I will be conservative at times or more aggressive depending on the situation."

Flower believes Cook is a "natural leader" although he knows the tour will be challenge for him. "I experienced snippets of that at Essex, and in the dressing room he is a strong character and makes good contributions," he said. "I think on the field he'll be respected by his players and he'll have to grow into learning the tactical game of which he's had very little experience."