Tiger Woods is not hitting full shots and has no timetable for his return to competitive golf after undergoing his fourth back surgery in April, the former world number one said on Friday.

In a wide-ranging post on his website that included thoughts about those affected by recent hurricanes and the earthquake in Mexico City as well as congratulations to outgoing U.S. Masters Tournament chairman Billy Payne, Woods said he is sleeping better and no longer has nerve pain going down his leg.

"I'm starting to hit the ball a little further - 60-yard shots. I have not taken a full swing since my back fusion surgery last April, but continue to chip and putt every day," the 14-times major champion said.

"I'm working out six days a week, alternating between the treadmill, bike riding, swimming and lifting twice a day. My muscle tone is coming back, but I'm not in golf shape yet. That's going to take time."

The 41-year-old said his six-month back X-rays are coming up at which point his surgeon will give him the parameters of what he can do moving forward.

"Playing wise, I'm not looking ahead yet because I don't know what kind of swing I'm going to use," said Woods.

"I just don't know what my body is going to allow me to do. Until I do, I'm going to listen to my doctors and continue to take it slowly.

Woods, who will be an assistant captain for the United States at next week's Presidents Cup in New Jersey, has not competed since withdrawing from a European Tour event in Dubai after a first-round 77.

But that has not kept him from engaging in some friendly competition, as Woods said he has hosted putting contests at his house with fellow PGA Championship winner Justin Thomas and world number seven Rickie Fowler.

Woods was arrested in May on suspicion of driving under the influence and a toxicology report showed he had five different drugs in his system, including pain and sleep medications.

A 79-times winner on the PGA Tour who was world number one for a record total of 683 weeks, Woods stunningly lost form in recent years due to injuries and the mastering of a new swing while his ranking has plummeted to a mind-boggling 1,136th after his long spell on the sidelines.

(Reporting by Frank Pingue in Toronto; Editing by Toby Davis) ((frank.pingue@thomsonreuters.com; +1-416-941-8094; Reuters Messaging: frank.pingue.thomsonreuters.com@reuters.net))