[steve86]

Just because a cohort of patients is diagnosed with MDD does not imply much about the severity of the disorder. MDD can be applicable as a diagnosis to high function, fully mobile patients who might well be good candidates for nutrition and exercise therapy.

More severely impacted patients who are not very mobile (often with profound slowing of gait if mobile at all) and are not responsive to behavioral suggestions are prima facie not good candidates.

[RoosterRedux]

But MDD is not low-grade depression (to use your term). It is clinical depression.

And you said, "For moderate to severe Major Depressive Disorder don't waste your time [with exercise].

Your statement just isn't true.

There may be exceptions of course, but your statement is general.

[RoosterRedux]

I imagine you know this, but this topic isn't a theortical exploration. There may be people reading this thread who are suffering from major depression and are on the verge of giving up.

Please don't discourage them by telling them that exercise isn't worth considering. It may not be the complete solution, but it can't hurt, can it?

I know because I've been there. I know exercise can work in many cases.