Ok, I know what you mean about the seated press.
If you're having a difficult time putting on good weight, etc. and the weather is bad, just stop the cardio for a while and see if it helps.
Are you sure you're getting enough protein? How much? And you need carbs and good fats to grow as well, so you need to keep track. Check out
www.fitday.com
You could follow the carbs with protein, or simply combine them. A popular mix is gatorade powder and whey protein, or maltodextrin/dextrose and whey protein. Take a look at
www.proteinfactory.com
Maltodextrin and dextrose are very cheap and perfect for post-workout recovery.
I mix 40g of Optimum Nutrition Vanilla Whey, 50g of dextrose and 15g of Gatorade Glacier Freeze powder (mainly for flavor). Mix it all up in one big bottle. I start drinking it 15 minutes before my workout, and sip on it throughout the workout, then finish it off at the end.
Also, for a good routine that may very well break through some barriers for you, check out the "Workout Routines" thread in the FAQ section. Take a look at Ian King's "Super Strength" and "Limping", and "Ripped Rugged & Dense". That will give you a good starting point.