This episode explores how and why hemoglobin's function emerges from its structure, which makes it a critical component in the oxygen distribution chain. We also discuss the lungs, why VO2max isn't related to hematocrit, and vascular capacity for blood storage before diving into a classic phlebotomy study that ends with a question mark that hints at the central importance of the heart.​

Show Notes
Blood value correlations with vo2max, Figure 1
​https://pubmed.ncbi.nlm.nih.gov/30549016/

Effects of detraining on cardiovascular responses to exercise: role of blood volume
https://journals.physiology.org/doi/pdf/10.1152/jappl.1986.60.1.95

Continuing the VO2max series, we take such a close look into the Fick equation we only cover one of its terms: the arterial-venous O2 difference.
We break apart the factors that affect diffusion of oxygen into our muscles, limiters of oxygen utilization, and whether these factors are trainable to potentially improve VO2max.

Show Notes
Determinants of endurance in well trained cyclists
https://pubmed.ncbi.nlm.nih.gov/3403447/

Hemodynamic adaptations to exercise
https://pubmed.ncbi.nlm.nih.gov/3993550/

One-legged endurance training: leg blood flow and oxygen extraction during cycling exercise
https://pubmed.ncbi.nlm.nih.gov/22059600/

The Fick Equation:
VO2 = Cardiac Output (A-V O2 difference)

Rate of diffusion for a gas across capillary wall:
Flux=[DA(C1−C2)]/T

The slow component of vo2max is often mentioned but seldom discussed. We take a deep dive into the nature of the slow component, including thermodynamics, fiber type, and the size principle.

Show Notes
Cycling efficiency is related to the percentage of type I muscle fibers
https://www.ncbi.nlm.nih.gov/pubmed/1501563

Muscle fiber recruitment and the slow component of O2 uptake: constant work rate vs all out sprint exercise
https://www.ncbi.nlm.nih.gov/pubmed/21160059

In the first episode in a VO2max series, we take a deep dive into why VO2max power, or maximal aerobic power (MAP), is not a simple number that can be found in a simple test. We discuss the history, physiological, and methodological underpinnings of ramp tests and what makes them flawed, and what some people have done to try and account for these. Additional methods of MAP testing and tracking and their drawbacks are discussed. We conclude with some practical advice for ways to monitor improvements your own VO2max.

Podcast Notes
Adami study on ramp rates
https://link.springer.com/article/10.1007%2Fs00421-013-2705-9

Second study on longer ramp rates
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6066218/

Coggan blog post on estimating VO2max power
​http://www.trainingandracingwithapowermeter.com/2010/06/how-to-estimate-vo2max-using-power.html

Pinot & Grappe VO2max model
https://www.fredericgrappe.com/wp-content/uploads/2014/07/MAP.pdf

Lactate remains a misunderstood molecule, and popular experts still don't have a full understanding of where it comes from or why. In this episode, Kolie explains the basic biochemical context of lactate, where it really comes from, and why we make it at rest and during exercise. You will come away from this episode with a good understanding of how enzymes catalyze reactions, the importance of always making lactate, and the kinds of things that cause demand on glycolysis.​

Podcast Notes
Metabolic pathway map
http://biochemical-pathways.com/#/map/1

BRENDA database entry for human LDH
https://www.brenda-enzymes.org/enzyme.php?ecno=1.1.1.27&Suchword=&reference=&UniProtAcc=&organism%5B%5D=Homo+sapiens

Today we discuss the global COVID-19 pandemic and its impact on cyclists. We start with basic virology and why it's through this understanding that we recommend even healthy people take extreme precautions. Then address group rides, and things to consider for your current training or re-planning your 2020 season for races that may or may not happen.

Show Notes
Background on corona viruses
https://virologyj.biomedcentral.com/articles/10.1186/s12985-019-1182-0

How long COVID-19 lives on various surfaces
https://hub.jhu.edu/2020/03/20/sars-cov-2-survive-on-surfaces/

Homemade masks, efficacy and breathability
https://www.researchgate.net/publication/258525804_Testing_the_Efficacy_of_Homemade_Masks_Would_They_Protect_in_an_Influenza_Pandemic

Analysis of early outbreak in Lombardia
https://arxiv.org/abs/2003.09320

​We asked for questions, and we got them. Kolie and Kyle answer eleven excellent questions on FTP training.

Delving into the biochemical depths of all life, Kolie discusses chemical equilibrium, or disequilibrium, and how ATP's high energy phosphate bonds aren't really what give it the energetic potential it's known for.

Show Notes
Nature, ATP definition
Bioenergetics 4

Today Dr. Helson runs the numbers on how much rotating weight matters when accelerating. The answer may (or may not) surprise you.

Show Notes
Rotating weight google doc

Whether we should pace endurance rides by heart rate or power is a training question where the usual answers lack sufficient depth. In this episode we provide enough context, and an alternative, that you might find the right style of riding for yourself.

Show Notes
High Efficiency of Type I Fibers Improves Performance
https://www.ncbi.nlm.nih.gov/pubmed/8005729

The slow component of oxygen uptake during intense, sub-maximal exercise in
man is associated with additional fibre recruitment
https://www.ncbi.nlm.nih.gov/pubmed/14758477