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He is focusing on carb metabolism and other health-related issues. Those issues aside, I think general conditioning, or training as he terms it, calls for both strength and cardio-endurance efforts. Of course intensity is key, which is why walking has no fitness benefit for those under age 80. If he has arguments against burpees, heavy rope games, stepping routines, and jump rope, I'd listen to them because those calisthenics are strenuous, difficult, and basically unpleasant.
My simple theory is that if physical efforts are stressful and difficult to the point of pain and failure, they will make you better (as long as you are not truly injuring yourself). It has to be hard as heck.
I'll take a whack at it.
Calisthenics are a form of aerobic exercise. Easily trained and quickly adapted to and the benefits are quickly lost if training is stopped.
Strength training, while anaerobic in most instances, takes longer to gain and the stress / recovery / adaptation cycle takes longer to attain, but the adaptation stays with you for much longer as well.
You can derive the benefits of aerobic training using a "prowler" or an "Airdyne" in a shorter time frame. And if "pain" is your measure of the worth of an exercise, I can guarantee you an unpleasant stint using either of the two mentioned.
It is better to gain and carry strength into ones later years. The basic activities of daily living are strength based, not cardio based.
Carrying in the groceries, climbing the stairs, getting in and out of a chair, toileting all require basic strength. A quick perusal of any senior living community will show a majority of residents lacking the ability to meet these requirements.
Barbell training is big medicine for the senior cohort.
The best exercise program is the one each individual will actually DO. Arguing over which is best is rather pointless in my opinion. Some people might prefer lifting weights 3x per week for years, others might prefer running or biking.
I'm pretty sure if you can still run a 10k in an hour, or swim a mile in an hour at age 80 you won't have any problems getting out of a chair or carrying groceries up the stairs.
My Mom (88) is currently in a facility with "independent" and "assisted" living, with residents of all types of abilities/disabilities. I will note that I have not seen many people that look like they were former football linemen that seem to have survived into their 80s. I don't know if that means anything or not, just an observation.