Stationary bike question?

[gleek. (:]

Okay, so I'm really desperate to lose weight, and I've been eating a healthier diet, and I'm investing in a stationary bike.

If I would cycle for 30-40 minutes three times a week, would it make a significant difference if I kept up the diet and kept on with it?

By the way, I'm 15, 5' 8'', and 175 pounds, but very solid, just a bit of a belly and my thighs are bigger than I'd like them to be.
By the way! I do get exercise otherwise, I'm just talking about this as a more intense workout. I have P.E. three times a week as well.

 

[glassjester]

The recommended amount of exercise is 20-30 minutes 5 times a week, minimum, for everybody! Not just if you're trying to lose weight.

Obviously the intensity of the exercise matters the most. Since you're investing in your health anyway (awesome!), you should get a heart rate monitor. Keep your heart rate at about 150 - 160 bpm for 45 minutes 5 times a week. You'll definitely lose weight.