How much time on a spinning bike should i spend daily to get reallyyy thin?

Im 17 and when i was long distance running my legs got soooo thin but toned. But i hurt my knee awhila ago so i cant run anymore :(
but im buying a spinning bike for my room.

how can i ride a spinning bike the right way
and how long to get really thin thighs, hips, ect. ???

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Recommended Answer:
Start out with an easy 10 min warm up in 3 steps. You want to pedal at 70-90 rpm with just enough resistance to get your heart rate to 85% of max. Start out with a 30 min goal and extend it to a hour or more. I shoot for two 60 min sessions, cut back on the food and you can lose weight like crazy.

You want a cold place like a garage or a fan so you don''t sweat like crazy.

• As much as you used to run.
• 4 hours a day
  ought to do it