I want to get a toned stomach and have been reading about that to get one you need to do cardio exercises as well as crunches etc, I have just got my bike fixed but does anyone know if bike riding helps you lose weight I'm not overweight by a long shot just want to my stomach a bit flatter so I can tone it, if this works is there anys suggestions on how long I should do it for, thanks

Cardio is pretty much essential to get a flat stomach, but more important is your diet. Bodybuilders have a saying "A six pack is built in the kitchen, not the gym."

Interestingly, crunches are not the best way to get a flat stomach. You'll end up with a layer of fat over very strong stomach muscles. You need to lift weights and work all your muscles. The exercise that works your stomach muscles hardest is barbell squats, not crunches.

Okay, the bike. One very interesting study compared two groups of women. One group did 40 minutes of moderate intensity bike riding three days a week. The other group did HIIT (high intensity interval training) where they went flat out for two minutes, followed by three minutes of easy cycling, and repeated for twenty minutes. They did half the amount of exercise as the first group, but lost more fat off their waist, hips and thighs.