Reference no: EM133602544

QUESTION 1

A group of friends go every Sunday to an early morning spin class then get brunch together afterwards. The spin class lasts 90 minutes, and for some reason is just at a steady pace the whole time. The class is approximately 50% of the individuals' maximal aerobic capacity.

The friends arrived too early and were seated waiting for a while (resting). Then class began without any chance to warm-up. The group has to suddenly begin cycling.

1. What will happen to heart rate now as the group begins their session, and how is this being regulated/controlled (physiologically)?
2. Heart rate isn't the only thing that changes. Tell me what will happen to their stroke volume, then list and describe 3 things that are leading to this change.
3. What will happen to their blood-flow / blood-flow-distribution, and how is this being regulated/controlled (physiologically)?

The cardiovascular system doesn't work alone. The pulmonary system has to bring air into contact with our vascular system for gas exchange to occur.

1. What happens to tidal volume and breathing frequency once exercise begins?
2. Beyond the lungs, changes also occur in the skeletal muscles which help to facilitate gas exchange. What 2 conditions change in/around the skeletal muscles during exercise to help facilitate gas exchange? (and again, what's causing/regulating this physiologically)?

The spin class is ALMOST done. They have been going for ~60-75 minutes and have ~10-15 minutes to go before finishing (ie, they have not finished yet). The whole group has been working hard (or rather at 50% of their capacity) and everybody's sweaty.

How does the cardiac output currently compare to the cardiac output at the beginning of the class (ie, min. 10-20 vs. min. 80-90)?

Describe the physiologic cause for how/why things have either changed or been maintained?

QUESTION 2

This table describes the cardiovascular variables of two individuals of identical mass and age as they move through incremental exercise from rest all the way to maximal exercise.

Review the above information and..

1. Determine who is has more cardiovascular fitness (who's more highly trained?).
2. Then, using the data in the table, give evidence for your conclusion about who is more fit.

These two individuals have different maximal aerobic capacities. The concept of maximal aerobic capacity can be described by the Fick Equation (VO2max=Qmax(a-v O2diffmax)). Despite having different maximal aerobic capacities, both of these individuals have a maximal HR of 200bpm. Using your understanding of the cardiovascular response to exercise, explain how they are able to have different maximal aerobic capacities despite having identical maximal heart rates?

Imagine these two are about to begin exercising at a steady work rate of 160Watts on an exercise bike.

1. As they are transitioning from rest to steady-state exercise, what will happen to their overall ventilation, arterial PO2, and arterial PCO2 (within the first 1-5 minutes)?
2. Once these individuals have reached their steady state, how will ventilation compare between these two individuals at this exercise intensity?