Mitochondria density vs. efficiency
When it comes to metabolic health, and using cardiovascular exercise as a lever to manipulate it, which offers greater "bang for the buck": mitochondrial density, or mitochondrial efficiency; or is it really both that we need to chasing, and with what kind of balance? Over a longer-term horizon, isn't it primarily Zone 2 training that improves longer lasting muscle capillarization and mitochondrial density, and by extension VO2Max? And over the shorter-run, wouldn't you possibly see greater improvements in mitochondrial efficiency with HIIT or Threshold training? Is fitness derived from mitochondrial efficiency potentially more "hollow"? I.e. would greater mitochondria density produce more fitness "staying power" vs. mitochondria efficiency? There are inevitable setbacks in life--injury, sickness, life stressors, etc.--that can get in the way of fitness pursuit. Given this, are there better long-term strategies to be employed in pursuit of our cardiovascular fitness and overall metabolic health?
Vaccine efficacy and danger
Hi Peter + Team, Do you mind giving an opinion regarding the third vaccine and discovered associated dangers? I am specifically concerned about the heart inflammation dangers for men. We are in Israel [population is highly vaccinated], and my family personally knows 2 people who suffered from heart issues after taking the covid vaccine. I am aware that the original claimed rate was 1/100,000. However, knowing 2 people in my immediate vicinity suffered from some complications makes me doubt these statistics. Additionally; I personally have 'felt' symptoms in the region of my heart since taking the first 2 vaccines myself. I am confident that this is not hypochondria; this feeling is certain and new. I am concerned that there is a misrepresentation about the safety of the vaccine. If we think of the cardiac symptoms as a spectrum b/w myocarditits / pericarditis and 'something minor happening'. Is it possible that the vaccine is causing a varying degree of heart damage in the large population of folks who are taking it. Appreciate you taking the time to read this.
Cataracts
In a number of podcasts you talk about indications and consequences of aging but cataracts are never mentioned. I am not an ophthalmologist but I would have thought that the progression or reversal of cataracts would be an aging intervention study that could be conducted quite easily.
Anabolic resistance
I enjoyed the recent AMA on exercise but I think it could be enhanced with a discussion around changes in muscle protein synthesis as we get older. The studies show that more protein is needed by older men (as usual I couldn’t see any studies on women) for MPS after exercise. Do some of the more extreme fasts (OMAD or multi-days) become detrimental to MPS as we age?