how much cardio!

Mesomorph:

The mesomorph has all the luck. This is the naturally- muscular person. They are characterized by having broader shoulders and a narrower waist (known as a "V" taper). They gain muscle easily and lose fat easily.

A mesomorphic person training to lose fat can get away with doing only one or two cardio sessions a week while still seeing fairly good results. They will have an easier time holding onto muscle while losing fat, which gives them a calorie-burning advantage (the more muscle you have, the more calories you burn in a day even while doing nothing). Mesomorphs who do more cardio sessions will see greater fat loss results than either of the other two bodytypes - their greater muscle mass helps them burn more calories.

The mesomorph has a relatively easy time gaining muscle. Their bodies seem to naturally want to add muscle and keep it. The mesomorph training for muscle gain should keep doing enough cardio training to maintain cardiovascular capacity (about once or twice a week). They can, however, still get away with doing more without compromising results.