Final answer:
The First Ventilatory Threshold (VT1) represents the point at which the body starts to rely more on anaerobic energy production during exercise.
Step-by-step explanation:
The First Ventilatory Threshold (VT1) represents the point at which the body starts to rely more on anaerobic energy production during exercise. At this threshold, there is a shift in the body's energy source from aerobic metabolism to anaerobic metabolism. This is typically characterized by an increase in breathing rate and the onset of fatigue.
Vital capacity (VC) is the sum of the expiratory reserve volume, tidal volume, and inspiratory reserve volume, and all are elements that participate in gas exchange, and play roles in a person's respiratory function during different phases of breath and physical activity. The VC along with other lung volumes such as total lung capacity (TLC), functional residual capacity (FRC), and residual volume (RV) are important for understanding overall lung health and capacity.
During exercise, as VT1 is approached and surpassed, heavier breathing is needed because of the increased demand for oxygen and the need to expel more carbon dioxide, influencing these capacities and volumes. Effective training can raise VT1, which allows an individual to perform at a higher intensity before the switch to anaerobic metabolism occurs.