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.
Blood value correlations with vo2max, Figure 1
Effects of detraining on cardiovascular responses to exercise: role of blood volume
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.
Determinants of endurance in well trained cyclists
Hemodynamic adaptations to exercise
One-legged endurance training: leg blood flow and oxygen extraction during cycling exercise
The Fick Equation:
VO2 = Cardiac Output (A-V O2 difference)
Rate of diffusion for a gas across capillary wall:
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.
Cycling efficiency is related to the percentage of type I muscle fibers
Muscle fiber recruitment and the slow component of O2 uptake: constant work rate vs all out sprint exercise
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.
Adami study on ramp rates
Second study on longer ramp rates
Coggan blog post on estimating VO2max power
Pinot & Grappe VO2max model
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.
Metabolic pathway map
BRENDA database entry for human LDH
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.
Background on corona viruses
How long COVID-19 lives on various surfaces
Homemade masks, efficacy and breathability
Analysis of early outbreak in Lombardia
We asked for questions, and we got them. Kolie and Kyle answer eleven excellent questions on FTP training.
Today Dr. Helson runs the numbers on how much rotating weight matters when accelerating. The answer may (or may not) surprise you.
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.
High Efficiency of Type I Fibers Improves Performance
The slow component of oxygen uptake during intense, sub-maximal exercise in
man is associated with additional fibre recruitment