ORLANDO (AFP) - Tiger Woods has revamped a swing motion from younger days in hopes of recapturing the form that has brought him 14 major titles, the former world number one said on Tuesday.

Woods, who returns from a four-month injury layoff when the Hero World Challenge opens on Thursday, says his nagging back injuries have healed and he has been able to rely upon muscle memory and motor reflexes in working with new swing consultant Chris Como.

"It's new but it's old," Woods said. "We went back to a lot of those old videos. It was interesting to see how much force I would generate with that skinny frame."

Two months of rest gave Woods time to analyse his younger form, with help from his mother's videotape machine, and look back in hopes of future triumphs as he chases the record 18 major wins of jack Nicklaus.

"Having an old motor path I remember has made the transition so much easier. My body feels relaxed about it," Woods said.

"I just haven't done it in a long time but my body is remembering it. It's familiar. It hasn't taken me that long to implement. I'm very pleased with my speed and the force I have. I'm able to produce speed and have range of motion. I don't feel I'm hitting it very hard and the ball is coming off the club faster."

Woods, who won his first major at the 1997 Masters at age 21, went away from his early swing motion because it produced knee injuries, admitting that he did not look back before because, "physically I was pretty damaged doing it".

But swing alterations in recent years led to more back injuries, including one that led to surgery last March to ease a pinched nerve. Woods struggled through four events in a mid-season comeback he halted after the PGA Championship last August in order to rest.

"The body is great. It feels fantastic," Woods said. "More strength. More range of motion. Now I just have to hit more balls. I still have some aches and pains like anybody else. I'm past the rehab portion of it. I'm in the strength and development portion of it."

Woods tees off on Thursday in the first round of the 18-player, US$3.5 million (S$4.6 million)) event at Isleworth alongside Australian Jason Day, also returning from a back injury.

The Challenge, which benefits Woods' charity foundation, will be played in the Bahamas starting next year, Woods announced.

Woods admits he is uncertain when he might be ready to contend for any title, much less win his first major since the 2008 US Open.

"Am I game ready? Probably not quite as much as I would like to be," Woods said. "It will be interesting to see on Thursday how long it takes me to get my feel back.

"I want to see where my misses are. Am I able to rectify them right away? I have a good understanding of what I want to do." Woods split with ex-coach Sean Foley last August in part because of the injuries.

"Physically I just wasn't able to do some of the things we wanted to do," Woods said. "We're still good friends. Professionally I felt I needed to go in a different direction." That led to Como and a meeting of minds.

"I was very inspired and very excited to see what he thought my swing should look like because it was similar to what my vision was," Woods said.

Woods said that for his numerous injuries and an infamous sex scandal that began five years ago at Isleworth, age has been his biggest career setback.

"Father Time is undefeated," Woods said. "We all start losing some of the things we've been doing when we were younger. We all have to make adjustments. I'm no different."

Woods also spoke on other topics, such as the shooting of a black youth by a white police officer in Ferguson, Missouri, saying "it's a sad situation all around", and his membership on a Ryder Cup task force charged with boosting US results after a loss by the Tom Watson-captained side in Scotland back in September.

"Our job is for us to have this task force only once, to create a matrix going forward where everyone is happy with the selection process," Woods said. "If we do our job correctly, we're only going to do this once."