Etia's current weekly exercise macro structure (unchanged over past year despite changing micro-structure in specific exercises) consists of: Tuesday, Thursday, Sunday as zone 2 cardio days (45 minutes each); Saturday as either dual zone 2 + zone 5 workout or single longer anaerobic bike ride; and Monday, Wednesday, Friday, Sunday as lifting days split into upper body (Wednesday, Sunday) and lower body (Monday, Friday), with lifting always done after cardio.

Exercise regulation involves not just oxygen delivery to muscles but also central factors like brain oxygen levels, with the brain using oxygen thresholds as 'circuit breakers' that reduce muscular output to maintain adequate cerebral oxygenation even when muscles could theoretically work harder.

Peter performs a 10-15 minute deadlift preparation checklist of approximately 10 exercises before deadlifting that may provide benefits equivalent to or greater than the deadlift itself in terms of stabilization and movement preparation.

Backcasting from desired end-state capabilities (determining what you want to be able to do at age 100 and working backward) is a more effective planning framework than forecasting forward from current age.

Zone 2 training benefits include metabolic benefits (glucose insulin-dependent and insulin-independent glucose-mediated disposal), mitochondrial function and density improvements, and BDNF secretion from this type of low-intensity aerobic activity.

VO2 max is the maximal amount of oxygen per unit time that a person can process—the rate at which oxygen is taken from air into lungs, into blood, pumped to muscles, and used metabolically—and was first formally described in the 1920s by A.V. Hill who observed a plateau in oxygen consumption at maximum workload intensity.

The 20/10 Tabata protocol (20 seconds work, 10 seconds rest) is favored by researchers because it prevents conscious or unconscious pacing, whereas the 10/20 variant allows people to complete all rounds by pacing themselves, meaning the 10/20 can be performed at higher absolute intensity but the 20/10 forces confrontation with true maximal effort.

Conventional wisdom has been that lungs are not a limiting factor for VO2 max because they are 'overbuilt', but recent research suggests that in highly trained endurance athletes, the lungs can be a limitation, and elite athletes can experience exercise-induced arterial hypoxemia even at sea level due to insufficient oxygen diffusion time as blood passes through the pulmonary capillaries.

High-quality Pilates teachers often teach the same stability and force transmission principles as DNS practitioners despite using different terminology, making the choice of discipline less important than the quality of the teacher and student understanding, with other valid approaches including Postural Restoration Institute (PRI) and dynamic neuromuscular stabilization (DNS).

Most people fail to realize how little actual time under tension occurs during typical weight training sessions; for example, a 90-second continuous time-under-tension protocol (as advocated by Doug McGuff's 'Body by Science' approach) represents an eternity of sustained muscular load compared to traditional lifting.

Etia had a cycling peer with lower VO2 max (55-60 ml/kg/min vs his 70 ml/kg/min) who was consistently faster on the bike, suggesting efficiency and other factors beyond VO2 max determine performance, meaning VO2 max is useful for self-comparison over time but not for predicting outcomes between different athletes.

Zone 2 training is characterized by effort below the level that would raise heart rate above 120 bpm while swimming, allowing Peter to exercise with no agenda other than aquatic immersion, without pushing intensity or measuring pace.

The majority of centenarians alive today are centenarians because of exceptional genes, not lifestyle optimization, and on average they tend to smoke more, exercise less, and eat worse than their peers, meaning the deliberate approach to becoming a centenarian through training and lifestyle hacking is a completely new model distinct from existing centenarian populations.

Performance optimization and longevity optimization are often orthogonal or opposed—pursuing elite athletic goals like breaking 2:40 in a marathon, completing a 10-hour Ironman, or deadlifting 3.5x body weight requires training at energy systems that are past the point of optimizing longevity returns and actually comes at longevity cost relative to lower-intensity training.

The centenarian olympics/decathlon is an 18-item list of functional tasks that an individual wants to be able to perform at age 100, including activities like getting up off the floor with single-arm support, dropping into a squat to pick up a 30-pound child, lifting 30 pounds overhead, and getting out of a pool without a ladder.

Muscle mass declines at a minimum rate of 0.3-1% per year, with other studies showing 1-2% annual decline after age 50, and total lean mass decline between age 20 and 80 reaches 35-40%, while strength losses are even greater at 2-4% per year, making average performance at age 50 incompatible with high functional capacity at age 85.

The deadlift, when performed with correct positioning and intra-abdominal pressure, can actually place the spine under traction despite axial loading, which is counterintuitive but biomechanically possible when spine elongation is maintained, and this spinal traction benefit is why deadlifting is the most important pre-flight activity because it primes spinal activation that prevents compression during prolonged sitting.

Etia checks lactate levels four times per week during zone 2 training to verify intensity maintenance, knowing his exact zone 2 wattage, heart rate, and corresponding lactate level, and will reduce wattage to achieve target heart rate if it is significantly elevated (signaling illness, dehydration, or other physiological stress).

VO2 max is reported in two metrics: absolute liters per minute (which scales with body size and doesn't allow fair comparison between athletes of different sizes) and relative milliliters per minute per kilogram of body weight (which normalizes for body size), though both metrics have limitations because whole body weight includes non-metabolic tissues like skeleton and adipose tissue that don't scale with oxygen utilization.

A person cannot truly go 'all out' for more than 10 seconds; beyond that point, even elite athletes are pacing themselves consciously or subconsciously, as demonstrated by Usain Bolt slowing in the second 100m of the 200m sprint despite having a flying start.