I’m sure I’ve made some inexcusable mistakes somewhere in the process of writing this.
Found it. :P (Well, kind of.)
And if exercise has antidepressant effects in humans, then the claim that those effects are neurogenesis-mediated must be wrong too.
Apparently exercise correlates with less depression, but isn’t causal. That is, depressed people tend to exercise less, but exercising more doesn’t cause you to be less depressed.
Unrelated tangent thought: I’d really like to know if the huge correlation with lifespan/healthspan has the same issue. Like, I’m pretty sure VO2 Max is the metric we should be optimizing for, rather than a target weight or muscle mass. Like, once you control for excercise, weight is no longer a strong predictor of health/lifespan.
But maybe exercise has the same problem. If most people have a hard time doing callorie restriction, but can up their metabolism through exercise, then the only benefit of excercise might be avoiding a caloric surplus. Or maybe exercise isn’t causal at all, but the sorts of people who exercise also do other things that help, or are just healthy enough to be able to exercise.
I do not have depression, but exercise seems to have an effect on my mood (and anecdotally appears to have similar affects on friends of mine, depressed or otherwise). Is part of the argument here that exercise doesn’t have any reliable effect on mood? (i.e. I’m placeboing myself or not noticing that sometimes exercise doesn’t affect my mood or does so negatively or something?).
Or just that it doesn’t have any longterm effects on depression? (so a depressed person might feel a bit better via the same mechanism I do, but in a dimension that’s different from “depression?”)
Sorry; normally I try not to make claims like that without a citation, but I was on my phone at the time and couldn’t find the source easily. But here it is:
It’s a twin study with 5952 participants. Here’s the highlight:
In genetically identical twin pairs, the twin who exercised more did not display fewer anxious and depressive symptoms than the co-twin who exercised less. Longitudinal analyses showed that increases in exercise participation did not predict decreases in anxious and depressive symptoms.
Conclusion Regular exercise is associated with reduced anxious and depressive symptoms in the population at large, but the association is not because of causal effects of exercise.
Maybe everyone’s mood still goes up a little from exercise, due to endorphins or whatever? Like, I assume that people with depression can still experience runner’s high, just like I’m pretty sure they can still experience a heroine high. Maybe it’s numbed or less intense or something, I dono. But neither is going to cure their depression. Or, at least that’s my interpretation. (Maybe a permanent heroine high would count as a cure, if it somehow didn’t kill you?)
For whatever reason, they display about the same levels of depressive symptoms, regardless of exercise. But, I assume that those symptoms are somewhat independent of moment-to-moment mood, or how you feel about something in particular. So, it seems perfectly possible for the mood effects of exercise to be real, without conflicting with the study.
Personally, I don’t think exercise itself has much effect on mood, aside from runner’s high, which seems well-documented. Playing a game or sport definitely can, if you let yourself get really into it, but I think that’s mostly independent of the physical exertion. But, all I have to back up this particular impression is personal subjective experience, and most of that has been doing fun things that also happened to involve physical activity.
Found it. :P (Well, kind of.)
Apparently exercise correlates with less depression, but isn’t causal. That is, depressed people tend to exercise less, but exercising more doesn’t cause you to be less depressed.
Unrelated tangent thought: I’d really like to know if the huge correlation with lifespan/healthspan has the same issue. Like, I’m pretty sure VO2 Max is the metric we should be optimizing for, rather than a target weight or muscle mass. Like, once you control for excercise, weight is no longer a strong predictor of health/lifespan.
But maybe exercise has the same problem. If most people have a hard time doing callorie restriction, but can up their metabolism through exercise, then the only benefit of excercise might be avoiding a caloric surplus. Or maybe exercise isn’t causal at all, but the sorts of people who exercise also do other things that help, or are just healthy enough to be able to exercise.
This seems real weird to me.
I do not have depression, but exercise seems to have an effect on my mood (and anecdotally appears to have similar affects on friends of mine, depressed or otherwise). Is part of the argument here that exercise doesn’t have any reliable effect on mood? (i.e. I’m placeboing myself or not noticing that sometimes exercise doesn’t affect my mood or does so negatively or something?).
Or just that it doesn’t have any longterm effects on depression? (so a depressed person might feel a bit better via the same mechanism I do, but in a dimension that’s different from “depression?”)
Sorry; normally I try not to make claims like that without a citation, but I was on my phone at the time and couldn’t find the source easily. But here it is:
https://jamanetwork.com/journals/jamapsychiatry/fullarticle/210112
It’s a twin study with 5952 participants. Here’s the highlight:
Maybe everyone’s mood still goes up a little from exercise, due to endorphins or whatever? Like, I assume that people with depression can still experience runner’s high, just like I’m pretty sure they can still experience a heroine high. Maybe it’s numbed or less intense or something, I dono. But neither is going to cure their depression. Or, at least that’s my interpretation. (Maybe a permanent heroine high would count as a cure, if it somehow didn’t kill you?)
For whatever reason, they display about the same levels of depressive symptoms, regardless of exercise. But, I assume that those symptoms are somewhat independent of moment-to-moment mood, or how you feel about something in particular. So, it seems perfectly possible for the mood effects of exercise to be real, without conflicting with the study.
Personally, I don’t think exercise itself has much effect on mood, aside from runner’s high, which seems well-documented. Playing a game or sport definitely can, if you let yourself get really into it, but I think that’s mostly independent of the physical exertion. But, all I have to back up this particular impression is personal subjective experience, and most of that has been doing fun things that also happened to involve physical activity.