Originally Posted by Roody
I walk for fitness and hike for recreation. Otherwise, I will ride my bike even if it's only a block or two.
My (crack-pot?) theory is that imbalance in the leg muscles can contribute to knee and hip problems.
Remember Bob Marley? "My feet is my only carriage."
If you have strong quads but week hamstrings, you're asking for a pulled hamstring the first time you play tennis/raquetball/basketball or climb stairs. I'm not sure about knee or hip problems, but it is probably best to maintain some balance.
"Hamstring exercises are important because over-development of the quadriceps, typical in most serious cyclists, must be balanced with development of the hamstrings to avoid hamstring tears. Also, hamstrings are used in the bottom part of the pedal stroke where a slightly backward force is applied."
http://www.ultracycling.com/training/centuries3.html