Producing Lactate

• The sport of cycling has changed over time: watts and power output have decreased from the era drug use were rampant.
• It’s feasible that the future of cycling will include real-time physiology & output metrics of riders.
• Tour de France racers like Tadej spend 70-80% of the ti...

• Zone 2: the exercise intensity at which you are stressing mitochondria and oxidative capacity the most.
• Tenants of zone 2 training: recruits mainly type I muscle fibers, mobilizes the highest amount of fat oxidation, and stimulates bioenergetics (fat & glucose in mitochondria).

Iñigo San-Millán, Ph.D. (@doctorinigo) is an internationally renowned applied physiologist. His research and clinical work focus on exercise-related metabolism, metabolic health, diabetes, cancer metabolism, nutrition, sports performance, and critical care  

Iñigo San-Millán returns to The ...

• Hook the device up to yourself then ride a bike or machine and gradually increase the intensity, measuring VO2 and VCO2
• Consumption of oxygen production of carbon dioxide – which tells us total energy consumption (in kcal per minute).
• Ratio of VO2 and VCO2 tells us how much e...

As exercise intensity increases, you need more oxygen so VO2 increases then you give off more CO2 – you are recruiting type II muscle fibres, using more glucose for energy, consuming more oxygen, and producing more CO2.

Mitochondria oxidize fuels differently at different exercise intens...

• Some studies point to elevated lactate levels in patients on metformin
• Metformin carries a lot of potential long term benefits but it’s difficult to parse out effects on mitochondrial function
• NAD levels decrease with ageing, but many other metabolites are also downregulated ...

• A reasonable measure of how zone 2 should feel: you can carry out a full conversation, maybe not as comfortably as if you weren’t exercising, but still without much strain.
• You want to know your actual maximum heart rate – zone 2 will be about 70-80% of your realized maximum...

• Patients with long COVID, even if previously healthy, end up looking mitochondrially like patients with type 2 diabetes in terms of fat oxidation and lactate production.
• Metabolic test results of patients with long COVID often have normal pulmonary function tests and normal cardiac f...

• The brain dies if the liver can’t produce glucose continuously
• Muscles deplete glycogen because of high utilization but the liver has plenty of glucose because of gluconeogenesis
• It’s plausible that muscles eat themselves to feed themselves and the rest of the body – so getti...

• Tadej Pogačar’s unique characteristics: can sustain high amounts of power output over long periods of time, recovers well, highly trainable.
• Functional threshold power (FTP), lactate measurements, and watts per kilo predict performance – you really know where you stand before the rac...

• The independent variable is workload (in watts); the dependent variable is blood lactate.
• People with metabolic syndrome have high resting lactate (almost 2 mmol) – it’s possible that resting lactate will eventually be a tracked biomarker (the same way we use blood glucose).
• ...

• Zone 2 really involves steady-state, sustained cardio.
• If you only train once per week, you will deteriorate overtime – two days per week you might maintain what you have – three days or more, we see improvements.
• Ideal parameters of zone 2: ideally train 1 hour-1.5 hours, 4x...

• Four pillars of fitness: (1) stability; (2) strength; (3) “low-end aerobic” or zone 2; (4) high intensity/anaerobic capacity.
• VO2 max is highly correlated with longevity.
• Longevity is also highly correlated with mitochondrial function and metabolic health.
• High-intens...