definitions:

Fitness:
ability to do work without becoming tired. It is a combination of strength, endurance and flexibility.

Strength:
Muscular= maximum force a muscle can exert in a single contraction e.g. holding up a heavy weight.
Dynamic=ability of a muscle to contract at a speed while overcoming resistance/exerting force rapidly e.g. sprinting/cycling

Flexibility:
The range of movement at a joint. (Without pain)

Endurance:
The ability to work out for long periods of time without getting tired.

Aerobic fitness:
Person’s capacity to take up and use enough oxygen to sustain work for long periods. To measure aerobic fitness calculate vo2 max.

Vo2 max:
maximum volume of oxygen a person uses per minute per kg of body mass during exercise.