The difference is that cardio focuses mainly on your cardiovascular system which is vital in activities such as running, swimming etc. Strength training is mainly based on well, strength. How much weight can be lifted. so the difference really speaks for itself. A runner will mostly do cardio whereas a football player will mainly focus on strength. Both can be used simaltaneously in a work out.
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This is false, because they do provide calories (actually a lot), but do not have nutritional value. They are "empty" in nutrients, hence the name "empty calories."
To be frank, the main consequence would be simply not achieving that goal. Setting an unrealistic goal means that it's probably pretty hard to achieve, but you may not see it that way, so when you eventually fail or mess up, like any normal person would, you will be extremely discouraged, when in reality there is no reason to be disappointed in yourself given the goal was unattainable in the first place. You may feel inferior and it might lower your self esteem because you thought that the goal should have been achieve able.
