Walshmiko,
Your post brings to mind that which many fly fishermen neglect. That is the importance of maintaining ones physical viability. I have found this to come into play particularly in high gradient pocket water where wading can be unpredictable. The first and foremost concern is ones personal safety, however, physical capability can also obviously affect our fishing experience as well. As a person who deals with some what of a weight issue I can say first hand that this can affect ones balance and endurance for sure. So the gym is a great idea during this less active time of year to prepare for a great 2010!