I can definitely see a difference in the way I feel after cycling. I rode for 2 hours yesterday and didn't even feel it. (I should probably step it up when I get a bike that fits) Today I will run an hour and be wiped out. It makes it tempting to skip the run and go for a ride. I have always wanted to do a triathalon but worried about the biking part. I am a decent swimmer and runner but never biked. I am still getting comfortable riding in the road, changing gears, and paying attention. It is certainly something I will do in the future now that my "fear" of bikes is over. Thanks for the advice everyone. I am going to try to do 90 miles this week and just increase it slightly every week. I should be better at listening to my body now than I was when I started running.