I agree with the year round exercise... I started riding mountain bikes last May to get in shape after a bout with Prostate Cancer.  Last August I graduated to a road bike, and since then I have lost between 42-45 pounds, and have increased my stamina greatly.  
The wife and I ride around 125-150 miles a week (20-30 3-4 times a week Sun-Fri evenings) and a good long ride of 50-60 plus on Saturdays.  
I also paddle solo in a Wenonah Wilderness with a solo canoe Paddle (260 cm Bending Branches Sandpiper Twilight double bladed paddle) to where I can paddle 10 miles or more easily.  
Of course other than the occasional eliptical workout, and riding on the trainer in bad weather that is all we do, no weights. Although we do sit-ups and some core stretches.
And most of the time I watch what I eat and eat what is good for me now.  I am looking to loose about another 20 pounds before my trip at the end of June this year!

Bruce