Old brake hoses can also cause problems as they can develop a sort of one way direction where the brake fluid will not flow back after releasing brake pressure keeping the cylinders under pressure
Yes, I had that problem too. The braiding inside the hose rusts and expands closing the hole. Brake fluid goes one way under pressure from the pedal but won't flow back easily causing the brakes to bind. The brake hoses look fine though as you can't see the braiding inside the rubber. Open the bleed valve and if you still need to apply quite a bit of pressure to the pedal for the fluid to come out, replace your hoses.