Ed, Another place I just thought of that would be closer to home is the hike/bike trail from Bay Area Park past Armand Bayou to Red Bluff to Kirby. It's about 6 miles round trip but you could do it several times. Also the loop around Bay Area Park is about .8 mile but beware the aggressive geese in the vicinity of the fishing pier. The whole thing is totally flat but you could swing by the Kemah-Seabrook Bridge to really get those thighs burning.
