the definition of Fitness.

'the ability to carry out daily tasks with vigor and alertness, without undue fatigue, and with ample energy to enjoy leisure-time pursuits and respond to emergencies.'

break it down..

fitness is basically a state of physical and mental wellbeing with the energy to enjoy life and survive fight-flight situations.

You can't claim to have fitness if you don't know THE EIGHT COMPONENTS OF PHYSICAL FITNESS.

Follow the thread.

Cardio endurance- how long can your heart and lungs work to keep you active without tiring?

Do you gas out from climbing two flights of stairs or a quick dash down the hall?

Muscular endurance- for how long can your muscles work when doing a repetitive movement.

Can you hold a position for longer when having sex without tiring?

Muscular strength - how strong are your muscles against external weight?

Can you carry your wife and make her feel like a princess.

Muscular power - how much force muscles can your produce. This involves speed in muscle action.

Can you jump over a puddle ladt minute?

Flexibility - how far can your body stretch?

Can you bend forward to touch your toes?

Balance - how stable is your body in space?

Are prone to falling?

Speed - how fast can your body move in space?

Can you catch up with a runaway trolley in the mall parking lot?... Call the insurance company.

Body composition - What's the ratio of fat tissue to other tissues in the body.

Are you fat or lean or inbetween?

You'll see some examples I gave for one component could easily apply for some other components.

Can you think of the major components you'll engage when chasing a runaway trolley?

So now thunk about your physical fitness... Have you got it?

To what level?
If you don't know what I'm talking about.
Read this thread.