I'm not questioning his dedication, just reckon if he'd taken taken better care of himself he would've prolonged his time at the peak of his game. His decline started before he hit his 30s. With all the evidence around us of him doing stupid shit - getting battered, smoking, getting KOd, putting on weight in the summer, etc - it's not ridiculous to think this may have impacted his longevity.
I think that's a fair point to make but it is also a massive ask of a sportsman to do all that . Maybe its general lack of nouse on his part . The feeling that he could achieve a level because of his natural ability after taking his foot off the pedal for periods of time but not really appreciating that it gets harder and harder to do . His build does have a lot to do with it though and he hasn't really had too many injuries ( compare him to Sturridge ) in his career . He is still a very good player and is certainly no back number as far as EFC are concerned .