Luke Ablett is hoping he has turned the corner in his recovery from a hamstring injury to return in four weeks.Ablett missed one game in the latter stages of last season with a back complaint and then limped off with a hamstring injury in the early stages of the first quarter of the grand final.While it should have taken a few weeks to recover, Ablett learned it wasn't as simple as he had hoped."The injury is related to the hammy I did in the grand final," Ablett told sydneyswans.com.au."The hammy had muscle and tendon damage and has not all healed but last year I also had a lot of back pain and nervy hammy stuff too and that came back."We didn't really know why but it turns out my right glute, which is on the side I did my hammy, wasn't working as well as it should be."All my core stability has basically disappeared and a lot of the smaller muscles like the ones in my back are also not working really well so it has all combined together to give me this nervy sensational whenever I run for half an hour or more."The last few weeks I have been doing faster run-throughs to build up my speed and then fartlek runs (when, for example, they run for 30 seconds then jog for 30 seconds) and it is then after about half an hour of running that it was starting to get sore."It is weird as usually coming back from a hammy sprinting is the last thing you can do and once you sprint you can usually start to train and play but for me it isn't a muscle injury, it is more back and core related."Ablett has done plenty of exercises to improve his core stability to get everything working properly and is hoping he can put the months of frustration behind him."Last week was promising as I ran pretty much flat out on Monday and then did a bit more interval stuff the following morning which involved some longer runs combined with sprints and it felt pretty good, and that was 35-40 minutes or work so that has been a really good sign," he said."I don't know how long it is going to be at the moment as up until the last week we haven't really known what has been going on exactly."It has been up and down and really frustrating, just the not knowing, but the last few days we have got a new theory so hopefully it won't be too much longer."As to a return date, Ablett isn't thinking too far ahead but only wants to return when he is 100 per cent."I haven't done much so when I return will be determined by where my fitness levels are but I think if everything goes alright from here it will be pushing towards that four week period," he added."Over the next few weeks I am really going to work on my fitness and then my skills but based on the fact that I have done nothing since the grand final I will probably have to play a few games in the reserves."Though to be honest I haven't really thought about the season as it has just been about getting my body right and my hammy right, and once I start training with the boys I will start thinking about playing games and what I need to improve on."