View Full Version : mental vs physical stress and food intake?

05-29-2011, 11:26 PM
I'm not quite sure how to phrase this, so bare with me.

Someone who is physically active and exercising, while consuming the right diet will gain/lose weight.
If this person began working a less physically active job (Say he was a carpenter) and began working a more mentally exhausting job (A job at a desk punching numbers, perhaps not as fun but better pay) would the switch from physical exhaustion to mental exhaustion require a change in diet to maintain his goals as far as the gym goes? Or would a calorie reduction most likely be required?

As I have mentioned in previous posts, I have some serious issues with my work that is mentally exhausting. My body feels like it can go to the gym, that I'm eating enough. My brain is, however, maybe not quite ready. The brain isn't a muscle though it is an organ, so would a decrease in nutrition be wise even though you're less active overall?

Again, sorry if this sounds strange...I'm just not sure how to put it.

06-22-2011, 04:11 PM
The brain uses glucose directly from the blood stream (or ketone bodies, which studies have shown to be a much more efficient energy source for the brain) rather than storing ATP within tissue, and it uses a fair bit of energy just to keep your body ticking along nicely and alive (in fact more of the body's total energy than any other organ). Of course using more 'mental' energy requires higher use of various neurotransmitters and of course energy. Neurotransmitters and hormones themselves require amino acids for production, gene expression of enzymes (for protein gone), and of course, and ions used for nerve action potentials also require an energy input. That said, it's not possible to tell exactly what the energy difference will be if you switch from physical work to brain work, so I'd go for trial and error. This depends on how strenuous the former job was, your BMR, level of concentration and brain power needed, etc.

I know in my own case, I risk hypo episodes much more while studying than when training!

Personally I would keep the level the same for now and adjust according to how you feel, both at work and while training.