Can strength training replace aerobics

Absolutely not! I have thought that for years, and being 50 now I thought I was right...until, I started Surfing 1 year ago. The way I work out is strong and fast, bench to flys and back again, very quike paced. Your heart controls everything, it needs it's own workout, the heart needs and deserves the attention. Work you way up to 120 beats a minute and maintain that for 20 minutes. When I started out, in the Gym, on a bike, heart rate up 118/120 for 10 minutes, the next day 11 minutes and so on till I reached the recommended 20 minutes. I feel better, surf better might even live longer ! "Get in shape to surf, don't surf to get in shape"