Question

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.

Q7)

Given that the average distance of each leg is 170.5 km in distance, and sometimes undulating in elevation, you understand that fatigue is inevitable. The energy depletion model of fatigue focuses around the concept that depleted substrates are just one source of fatigue, particularly observed in muscle glycogen and phosphocreatine stores.  

1. As an aerobic event, why do you expect depletion in glycogen and phosphocreatine?

Why, specifically, is it crucial to replenish muscle glycogen stores prior to the next leg?

Q8)

As the event is soon approaching, parts of Hungary are experiencing a heatwave. Indeed, temperatures may exceed 32° Celsius during the first leg of the race leaving Budapest.

1. Will the ambient temperature have any impact on Vinnie’s performance?

In terms of thermoregulation, what physiological changes are likely to occur during this leg of the race? Explain how these changes may influence

Answer 1

7. The event of cycling is an aerobic event. But as the event starts for the first 2-7 seconds phosphocreatinine serves as fuel for energy. The phosphocreatinine anaerobically provides phosphate group to adenosine diphosphate in the presence of creatinine phosphate to produce ATP.
After the first few seconds body switches its fuel from phosphocreatinine to glycogen.
The glycogen is converted to glucose which acts as a substrate for kreb's cycle to produce energy.
Utilization of phosphocreatinine and glycogen as fuels during the first few minutes results in their depletion.
As we know that glycogen levels deplete during prolonged exercise sessions. It is important to replenish the glycogen stores before the next leg because glycogen acts as the main substrate for glucose utilized in energy synthesis. Also decreased glycogen decreases the blood glucose levels which may cause volitional exhaustion and damage brain cells. So it is necessary to replenish the depleted glycogen.
8. When a person exercises in a hot climate, his body temperature increases due heat produced by increased cellular activities. Increased body temperature activates the thermoreceptors which sends sensory impulses to the hypothalamus. The hypothalamus acts as a control centre and sends motor impulses to the blood vessels causing then to dilate and sweat glands to increase rate of perspiration. Increased perspiration increases the amount of sweat loss.
As Vinnie is exercising increased sweating results in increased loss of water and sodium from the body. This results in fluid loss and electrolyte imbalance affecting his performance.