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.

1)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?

2)Out of interest, you decide to measure Vinnie’s gross mechanical efficiency during cycling (i.e., the ratio of work accomplished to energy expended). You determine that he is 21.9% efficient. Please explain what efficiency is a measure of, where does this value sit within normal efficiency data and why you are unlikely to see values much higher (e.g., 50%)?

3)Within the alveoli, the partial pressure of O₂ is reduced from that measured in the outside air (160 mmHg) to approximately 105 mmHg.

1. What three factors contribute to this reduction in P_AO₂?

What values do you expect to observe in PO₂ and P_AO₂ when Vinnie is cycling at the peak of Stelvio Pass (barometric pressure = 543 mmHg)?

What impact would the change in P_AO₂ have on Vinnie’s performance?

4)

The longest leg of the race is 228 km, during which energy intake is critical. Glycolysis and β-oxidation are processes that break down carbohydrates (i.e., glucose, sucrose, fructose) and fatty acids, respectively.

1. Individually, what is the total ATP yield from one molecule of glucose and one molecule of palmitate?
2. How did you reach these numbers (i.e., substrate yield and use)?

Based on what you know about the yield and speed of these two pathways, do you recommend Vinnie ingest glucose or fatty acids during the race? (Hint, remember the cross-over concept)

5)

You recommend that Vinnie performs altitude training as part of his preparation for the race, a training approach that is novel to him.

1. What physiological changes would you expect in the short (i.e., acute), and long-term (i.e., chronic)?
2. How will the physiological changes influence performance in the short (i.e., acute), and long-term (i.e., chronic)?

6)

During a casual chat with a sport scientist from another team, they suggest preparing “finish bottles” for the longer legs of the race. Along with a dose of painkillers, a “finish bottle” typically contains an ergogenic dose of caffeine (i.e., approximately 3 to 5 mg·kg^-1 of bodyweight).

1. As a sympathetic nervous system stimulant, what acute physiological changes will likely occur following caffeine ingestion at these doses?

Additionally, caffeine has a mild effect at mobilising free fatty acids. Please describe what is meant by mobilisation, and how this may influence performance

7)

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

8)

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?

The presence of phytochemicals, antioxidants, and fiber in ________ make them nutritionally superior to supplements.

Salmon and sardines, walnuts, flaxseed and flaxseed oil, soybean and canola oil are abundant in

On amino acid titration curves, using pH, pKa, etc, how do we know which hydrogens to remove at which states? I know it has to do with the acidity, and that at low pH the structure gets protonated and whatnot, but how do I know the order in which to protonate/deprotonate?

A sample containing the amino acid alanine plus inert matter is analyzed by the Kjeldahl methold. A 2.00-g sample is digested, the NH₃ is distilled and collected in 50.0 mL of 0.150 M H₂SO₄, and a volume of 9.0 mL of 0.100 M NaOH is required for back-titration. Calculate the percent alanine in the sample.

Which one of these is not an allosteric effector of hemoglobin binding to O2?

a.CO which binds in the same spot as O2

b.2,3-BPG which binds in the middle of the tetramer

c.CO2 which binds at the N-terminus of the subunits

d.H+ which binds to the amino acid side chains disrupting IM forces

Q. A certain amino acid has the following elemental composition: C, H, O, N. In a combustion analysis, 3.263g of it was combusted to produce 5.910g of CO2 and 2.835g of H2O. Separate analysis determined that it is 19.17% N, and its molar mass is 150g/mol. Determine its empirical and molecular formula.

How does an increase or decrease in pH affect the composition and charge of a functional group(s)?

What is the orientation of a water molecule around a negatively charged ion? Positively charged ion?

Would nonpolar side chains make an amino acid hydrophilic or hydrophobic? What about polar side chains?

In emergency care unite, TPN prescribed to a patient weight 88kg. He needs the following macronutrient: 500 cc of 10% lipid fat – 48 g of protein using 10% amino acid solution and D70.

A) Calculate the total osmolality of the TPN.

B) How many grams of fat will be used?