I ride and run. 3 mile jogs (9 minute mile pace) on the hike & bike trail 2-3 times a week. I try to do hill repeats on my bike 2-3 times a week and then take my longer ride (25 - 35 files) on Saturday morning. I will occassionally go 4 miles on a run but want to not be too tough on my knees.
The runs and the hill repeats each take about an hour, door to door. They are similar in that both elevate the heart rate and keep it high for the bulk of the workout. The long rides give me saddle time and let me cycle through different levels of exertion.
Oh...and I run because I have a good running buddy and we have great conversations and motivate each other. When I go do my hill repeats, he goes out on the trail on his MTB.
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2014 Specialized Roubaix2003 Interloc Impala2007 ParkPre Image C6 (RIP)