What does the concept of 'balance' in fitness training refer to?

The concept of 'balance' in fitness training primarily refers to the control of body position. This involves maintaining stability and coordination of movement, which is essential for performing various physical activities safely and effectively. Balance is crucial in a range of sports and exercises, as it allows individuals to perform movements without falling or losing control, supporting good posture and preventing injuries.

When considering the other options, lifting heavy weights focuses more on strength training rather than balance. Running quickly emphasizes speed and cardiovascular fitness, while the frequency of workouts relates to the overall training regimen instead of the specific skill or physical ability of balance. Therefore, controlling body position is the correct understanding of balance in the context of fitness training.