Time to fix your form, guys, because you are not sitting on the stationary bike seat correctly, say the experts at Men's Health. You either sit too low or too high. And this is just not right. Here's why.

Too low adds stress on the knees. Too high rocks your hips from side to side. Both are uncomfortable and inefficient. You look funny too. Here's what you should do: sit on the seat and place your heel in the middle of the pedal -- where the ball of your foot would normally rest. Make sure your leg is fully extended, straight down, at the lowest point of the pedal rotation.

If you're already practicing perfect form on the bike, congrats to you. If you're not, get to work, my friends.