Full transparency ... my approach is a bit old school. There may be better, more efficient methods out there.
I use a Total Gym like this There are a bunch on CL. I placed milk crates under each end and replace the handles by the pulleys (left side of picture) with swimming paddles like these (you have to run some string through the holes and attach the paddles to where the handles attach to the cables). Then you can adjust the incline of the machine to vary the resistance and go for endurance or interval-type training. Putting the machine on milk crates or some other elevated surface prevents your hands from hitting the ground at the bottom of the stroke. It's not perfect, but I've definitely noticed an improvement in my paddling stamina.
Just noticed this thread and agree that any excercize is good! Just happens that I picked up a concept 2 rower off CL last week and it’s been great getting up a little earlier before work and doing some interval training with some good tunes on. Having been a smoker for more than 20yrs, my lungs really need the cardio and it’s a great full body workout IMO. I’ve been smoke free for about 6 or 7yrs now. Had to quit before they quit me. I just want to be able to keep surfing
Never stop running. I do that and also rowing on a good machine ( which there's only one: concept two) I know is expensive, but it is worth it get it used, or even at the factory they sell the used ones after the Boston regattas. I tried the other trainers, like total gym and so on, and they are crap, good for nothing. With the rower, you don't need much if you can do two series of 15 min each day, 3 /week, in a month you'll feel the difference
Most pools open at 5am for free swim. I have to tell you when i leave in the morning not even my dogs wake up. Nobody cares what you do at THAT time.
Just called a gym around the corner from my house and they’ve got that rower. Going to start a regiment ASAP. Not far into fatherhood and my guts already feeling it.
The long-term goal is getting your kid to surf. My 10-year-old daughter now forces me to paddle my butt off several times a week just to keep up. =^)