This is true for certain metabolic zones but not others. If you're sprinting then yes, you get a higher power output while pulling up on the pedal. However if you're going for any kind of endurance (longer than a minute) the limiting factor is not muscular but cardiovascular/aerobic, and using less efficient muscles (the ones used for pulling up) will actually hinder your performance since you'll need to be supplying those with oxygen, thus decreasing total cycling economy.