Sir Bradley Wiggins is dubious about his future prospects in the Tour de France, raising the possibility that he may not attempt to win the race for a second time, and hinting that the sacrifices winning the race demands of him and his family may prove too much in the future.

"For me it was always about winning the Tour," he said. "I've done that. If I'm honest I don't think I'm prepared to make those sacrifices again that I made last year, with my family and so on. I've achieved what I've achieved. I'm incredibly happy with that.

"If I do anything else after this it will be stuff I want to do, stuff that I'm willing to train hard and sacrifice for really. For me it was always about winning the Tour, that was a huge thing for me, a huge journey; I've been doing that four years. I don't know if I'd want to go through all that again to be honest. I've always had other goals and there are other things I'd like to try and do." Wiggins won't be drawn but one of these may be the Paris-Roubaix Classic, which he has always enthused about.

Wiggins also conceded that he now sees Chris Froome as Team Sky's de facto leader and he might well struggle to oust the Kenyan-born Briton from the No1 slot in the British team. That in itself may help determine whether the Londoner attempts a repeat of his 2012 victory. "Chris has really stepped up, he's delivered now and he looks like he's really going to be there for a few years to win a few Tours maybe.

"There has been a natural selection this year through Chris's performances and my performances that he warrants being the team leader; and if he wins the Tour, that continues through to next year. I can live with that. I didn't go to the altitude camp before the Giro because I wanted to be with my family; the kids are getting older and I like watching [my son] Ben play rugby and other things."

Wiggins has recovered from the knee injury that put him out of the Giro, and although he initially hoped to race the Tour de France, the condition required a visit to a specialist who advised him to take two weeks off his bike, ruling him out of the Tour. He is now in the second week of a six-week block of training and expects to return to racing at the Tour of Poland on 27 July. That will be followed by an event in Colorado, where he may also take in an altitude training camp, before the Tour of Britain from 15-22 September.

"That's a race I've always wanted to do well in. It's getting bigger every year and in terms of profile in this country it's a nice thing to do well in." The British Tour has a time-trial stage which will suit Wiggins and is handily located not far from his home in Lancashire. Wiggins' final target of the season will be the world time trial championships in Florence on 25 September.

"The Worlds was always a focus and if anything this gives me a better opportunity to focus on it. Doing the Giro and the Tour it was always a matter of how much would be left because there is an eight-week period from the end of the Tour to the Worlds which is a long time. This has given me time to stop after the Giro and I've got a nice chunk of time to get ready for the Worlds."

Wiggins was speaking to the Guardian at a reception to launch an attempt on the Etape du Tour by a group of star rugby players including Paul Sampson, Kris Radlinski and Paul Sculthorpe in aid of the Joining Jack charity which campaigns to raise awareness of Duchenne Muscular Dystrophy. For more information visit www.joiningjack.co.uk