Cause of iron deficiency
I’ve been stewing over your podcast about iron deficiency. I’m a fit 63 year-old woman recently diagnosed with iron deficiency. My question is, what caused it? I have a theory: for the last six months or so I’ve been adding HIIT and cardio training, which previously was just (fairly intense) yoga. Also, I’ve been on a one-meal-a-day diet for several years, which started with going keto in 2018. I’m now just low-carb, not strict keto. So back to my theory – I’m wondering if the higher intensity workouts, with no refueling within a few hours after, could have caused the iron plummet. This is the first time in my life I have ever had this situation, but also the first time I’ve ever had my ferritin checked. My hemoglobin was normal, but ferritin was right at the border of low. I was having severe heart palpitations and had trouble doing anything but breathing.
Rucking and Lumbar Spine Issues
I am now 75 years old. The attached MRI from 2019 shows an array of degenerative changes in my lumbar spine. With a focus on core exercises prescribed by my physical therapist, I've managed to eliminate the sciatic and other back pain for over four years now (except for stiffness in the morning and after sitting too long), and I've not seen my spine specialist since then. I continue to play singles tennis 3x per week. (It was interrupted for about 2 months last summer for an Upper Hemisternotomy AVR + Ascending Aortoplasty for bicuspid valve disease.) I recently also added rucking to my fitness activities based on the strong endorsements from you; but when I told my cardiologist he expressed concern about my past back problems. You recently had an excellent podcast (#287) with Stuart McGill on lower back pain and injuries, yet I don't believe rucking ever came up, nor do I think back issues were addressed in your recent podcast (#292) on rucking with Jason McCarthy. This would be a very helpful topic for me and I think others with degenerative (or other) spine or other back issues who are considering taking up rucking.
Improving VO2 Max with Excess Fat Loss
Is improving VO2 max as measure by ml/kg/min through losing fat a useful way of improving healthspan and/or lifespan? Intuitively to me it feels like the reason VO2 Max is so closely associated with ACM is because it is quite difficult to achieve elite levels while carrying excess body fat, and therefore those with high VO2 Max also don’t suffer from high body fat related causes of death. Basically, are you interested in only the VO2 max improvements that come from increasing the ml of oxygen you can absorb (increasing the numerator) or is losing fat an equally important lever in improving VO2 max (decreasing the denominator)