It is very common for lost time injured workers to gain weight, become deconditioned and to experience and exhibit) waning motivation.
It is not complex to deal with this problem.
The injured construction worker needs to deal directly with the reality that his assuming a passive role, giving up more of his existence, appearance and objects will not work for him
Becoming obese, inactive and verbally complaining will not change their plight. Being angry, embittered and defining themselves in terms of their misery will accomplish very little.
The patient needs to be directed to see how his own response to injury is actually worsening his situation and that taking a position of poor pain tolerance will make him worse in their his eyes. It will also erode how he is seen by people whom he respects and admires.
He to see the complications to his future that he is himself creating and how his current approach is not only ineffective but is actually severely counterproductive.
You cannot passively approach this pervasive pattern among males; you cannot merely diagnose the problem and then do nothing about it.
You must have someone actively and directly confront them with what they are doing, point them in the right direction and have them participate in their own resolution of this injury.