Eisnic: Agree completely about staying in the saddle when older or having knee issues. I have tailored all my bikes to this exact style....use gearing rather than standing on the cranks. I have noticed distinct improvement in my somewhat severe knee arthritis (stiffness & pain). Another rarely mentioned benefit of biking (esp spinning) for seniors is that it stimulates the lymphatic system (this relies on major muscle movement since it does not have an active pump like the heart)......which is a major detox system (our lifestyle accumulates a lot of toxins over the years). A final issue for seniors is balance....I have modified all my bikes by fabricating rear wheelbase extensions (including 3 road bikes) using pieces of aluminum plate and sliding dropouts along with laidback seat posts to lower the saddle to ground height so that I have a "flat foot" stopped position....no leaning, easier to mount, very stable. I ride all local pavement so no pedal strike concerns.