Question

BACKGROUND INFORMATION:

Vinnie is a professional road cyclist participating in the 2020 Giro d’Italia, a three-week race nearly 3,600 km in distance with some stages exceeding altitudes of 2,700 m above sea level (i.e., Stelvio Pass, Italy). As the newly hired head of the high-performance team, it is your responsibility to manage his preparation for the event. You must demonstrate to your team a fundamental understanding of physiology, the chronic adaptations expected from his training, and methods that could be implemented to improve the likelihood of success.

QUESTION:

Your first job was to schedule a VO₂max test for Vinnie to examine his aerobic fitness. After repeating the assessment several weeks later after an intensive training block, you notice that VO₂max has dropped, but there has been an increase in VT₂. Please discuss why VO₂max decreased and what impact both changes will have on performance?

Answer 1

VO2 max is the maximum amount of oxygen a person utilizes during intensive exercises. This is measured in liters or milliliters of oxygen per minute per kilogram of body weight. This is used to determine the cardiovascular fitness of an athlete. During intense training the efficiency of oxygen transport is increased in the body. Training lowers the resting heart rate and at sub maximal loads more blood is pumped into heart in every heartbeat. A before and after training tests shows a decrease in VO2 max because the decreased resting heart rate increases the blood flow to heart and thus more oxygen is delivered. This decrease the stroke volume and thus decreases VO2 max.The values depend on many factors like age, gender, body weight, training methods, altitude etc. In higher altitudes oxygen levels are low and so the consumption of oxygen decreases in higher altitudes. VO2 max levels is a threshold that shows the ability of a person to transport oxygen effectively during physical activities.So this can contribute to endurance sports like cycling. The ventilator threshold (VT) is the intensity of breathing while training at a point where lactate accumulates in blood stream as the training increases the lactate in blood faster than it can buffer. The first and second levels called VT1 and VT2 differs in the intensity in which the latter has high intensity. When lactate accumulates quickly the breathing should be quick as well. When oxygen levels are limited then pyruvate is converted to lactate to produce more energy from glucose breakdown. So during intense exercises the maximum intake of oxygen is reduced so the lactate production increases and is converted to energy that is used during training. But the lactate production increase to build up in the body faster than it is used. This increases the VT2. The high intensity exercises activate the fast twitch muscle fibers that have great speed with less endurance. When the VT2 reaches a point where the fast twitch muscles gets activated faster , it shows the ability of the exerciser to increase the speed and fitness needed for endurance sport events like cycling.