IMHO, 150min/week of “aerobic” exercise are insufficient for long-term longevity and metabolic health gains/maintenance…I would say that ~300min/week should be the goal. Furthermore (and very important), the concept of Zone 2 training is NOT about cardiorespiratory improvements (aka VO2max) but about metabolic improvements at the cellular and bioenergetic level, driven by an improvement of mitochondrial function. At least this is how I have seen it since I “coined” my definition of Zone 2 almost 30 years ago and have always used it the same way. Also, I encourage people to start talking more about metabolic training instead of “cardio” training. We have been doing it already for at least 2 decades in the world of high sports performance. All exercise intensities improve cardiorespiratory adaptations. However different training zones stimulate different bioenergetic systems leading to different cellular and metabolic adaptations. Targeting the right metabolic adaptations can have significant improvements in longevity and metabolic health.