You can go to a gym, sit on a machine and push or pull weight.
It will help you. No question.
It creates a metabolic event in your body, alters hormone production, increases muscle and other soft tissue strength. It might even change the way you look.
But, it doesn't do a lot for your brain.
Your brain is amazingly plastic. The connections in your brain change based on what you do and this happens over your entire life. Exercise that challenges your balance and increases blood flow has been shown to improve the "wiring" in your brain. And, recently, juggling has been shown to do the same thing.
Now, I'm not suggesting you take up juggling but if you're going to take the time to go to a gym or even just to carve out 30 or 45 minutes a day to exercise, then why not perform drills and movements that will help your brain?
For example, you can sit at a chest press machine and push the weight or you could do a push up. In the chest press machine, you're relatively static and stable. The push up involves more muscles, more coordination and if you add one more thing to the push up - stand up - it becomes a cardiovascular challenge as well. You start in a standing position, then move into the push up position, perform a push up, then return to standing and repeat. The movement of your body mass transforms this drill from a muscle training drill to one that includes coordination, balance, and a cardiovascular event.
Or, you could perform a push up using a suspension training device like the TRX. You anchor the TRX to something stable, a door or even outside to a tree limb, and then perform the push up. You can see a sample of this drill here. This movement is much more challenging to your brain because of the instability created by the suspension device.
When you train, train your brain too.
"Training induces changes in white-matter architecture."
Jan Scholz, Miriam C Klein, Timothy E J Behrens & Heidi Johansen-Berg.
Nature Neuroscience, Published online ahead of print 11 October 2009. DOI:10.1038/nn.2412
"Aerobic exercise training increases brain volume in aging humans." Colcombe SJ, Erickson KI, Scalf PE, Kim JS, Prakash R, McAuley E, Elavsky S, Marquez DX, Hu L, Kramer AF. J Gerontol A Biol Sci Med Sci. 2006 Nov;61(11):1166-70.
